# Installing a Logan QCGB.  Logan 9B to 400 adaptation.



## mjhenks

I have always avoided the change gears on my lathe.  It is just a pain to do for a lathe that really does not get  alot of use but is very useful when i need it.  I have always wanted to  install a QCGB on it.  This is my thread to do so.

The game plan is:

- Research, research, research.  
      I have yet to find this conversion done but i have read a few items in adapting QCGB's to larger Logans.
- Locate a suitable gearbox.
      From a 9B if possible but rumor has it that the 10" and 11" Logan's are the same.
- Figure out what, if anything needs to change or be added for the adaptation.
      I do not expect it to just bolt up.
- Get-er-done.

I have owned my Logan 400 for about 20 years.  (The logan 400 is a 9", short bed lathe.  It is VERY similar to the Logan 1400 and 9B)  It was made in the late 40's.  My Grandfather bought it in the 50's or 60's from a VW shop that used it to turn brake drums.   It was passed down to me.

Over the last 6 weeks i have undertaken a full restoration of the lathe once i found that the headstock bearings were shot.  That project can be seen here.  

http://www.hobby-machinist.com/showthread.php?t=20631

The restoration is not yet complete but i am too the point where i am slowing down as i wait for the last few bits to arrive.

In all honesty, i am already nearly complete with the first step and i have already located and secured the a QCGB from a 9B.  However, for posterity and to help the next guy who wants to do this i will step thru each part with what i have learned and done.  I believe this thread would also be helpful for anyone with a larger or different model Logan who wants to do the same.

Matthew


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## Redlineman




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## mjhenks

So like any good Engineer I started with research.  Honestly I thought I would find a tutorial out there all ready.  I know at the very least I would have to drill mount holes but i did not think it would be hard and others would have paved the way.  I did the basic Google search on Logan QCGB finding some info but nothing that showed the adaptation.  Many asking the same questions I was with the typical answer being "Don't try it unless you are ready to modify things".  I was on my own.

So, lets start at home.  

www.lathe.com is the home of Logan Actuator which is Scott Logan company.  I am not sure the connection that Scott is to the Logan of 80 years ago but he has the same name and he is VERY helpful and quick at answering questions in regards to old Logan's.  He also has spare parts for sale as well as a pretty active Yahoo group which he supports.  
(https://groups.yahoo.com/neo/groups/lathe-list/info)

This link directly asks Scott if the adaptation can be done.  Scott talks about the things that are the same and different covering the 9, 10 & 11" lathes.  My take away was that the 9" or 10" units were possible source for my 400 conversion but that the drive shaft would have to be adapted. 
http://lathe.com/ll-group-archive/adapting_a_qc_gearbox.html. 

Parts list to see what was the same and what was different.
http://www.lathe.com/gearbox.htm 


Searching the Yahoo group as well as forums like www.hobby-machinist.com and www.practicalmachinist.com and www.*lathes*.co.uk/*logan *further educated me on the parts involved but still no tutorial or clear path.

I always go to Ebay to find out what parts turn as well as general prices.  It is amazing what you can learn on Ebay as well as what you can spend.  How about a 3rd party option from "New All Western Aircraft" QCGB.  Aftermarket parts.  Cool.  More info on this option can be found here.  http://www.lathes.co.uk/westernaircraft/  They had units for Logan, Atlas & South Bend.  What the actual difference between them I could not figure out.  $90 new.  Sign me up. 


When all said and done I figured I was looking for a 9" or 10" box.  Ideally with little wear and including the drive shaft & input gears.  I figure I would have to adapt the drive shaft so that was not as important as the condition of the box and its parts.  I also expected to have to fully rebuilt it.  Cosmetics were not the concern but it needed to be complete.  I should note that the 9" model that had the QCGB was the 9B.  The 10" I believe was the 200 but I am not certain there.

Looking at the historical price on Ebay told me I should pay from $200 to $350 for a complete unit and of course 2 or 3 sold "last week" but I would not see another for 4-5 weeks.  

In the words of Yoda, "Patience you must learn"

Matthew


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## Redlineman

Hey Matt;

I believe Mr. Scott Logan is the grandson of the lathe company founder. That's what sticks in my head anyway from reading lots of stuff. The 800 series lathes were built fairly early on in the life of the company, eventually concurrent with the 200s, and seemingly almost identical with the exception of the QCGB and lead screw. Is lead screw what you refer to as drive shaft? Anyway, I think the 820 model is the one I am looking for here, being essentially a 200 with the QCGB. Quite a few poeple have done the conversion, as you have no doubt read about. AFAIK you need a box, holes in the bed to mount it, and a lead screw, but that is to convert a 200. I don't know about a 400. Likely a bit more. You'll soon know far more than I on the subject, if you don't already. That is not hard!


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## mjhenks

Redlineman.

Certainly my research is more focused on the 9" lathes.  You are right in that i found quite a bit more on the larger lathes.  Thank you also for the info on Scott.  It is awesome that he still supports us.

As this thread goes on, anyone who has additional information please feel free to add it.

As i go on, most of my info is going to focus on the 9" or 10" units.  As the lathes get bigger i think the QCGB changes alot.

Here are some of the better pictures i have gathered in the spirit of research.  Some of these are harvested from the net so if it is yours and you do not want it posted please let me know and i will remove it.

These are a few general pictures of QCGB on machines.






These are comparison  shots of a 9B box next to a modern Powermatic box. Very similar in size and layout giving hope.  (This is an 11" lathe)  





Details of the 9" parts.  This is the drive shaft end.  (Lead screw)  I am convinced that i can take a 400 lead screw and turn the end to match this and re-cut the woodruff key.  The 400 does not need the key slot as it does not have power cross feed.  If you are adapting an powered apron in your own project then you would need the slot.  I think milling that would not be too hard either.

Some Dim's from a 9B-28
Tip of lead screw to first thread is 8.04"
Overall Length 39.75?
Right end of lead screw to gear box right side shaft bushing (collar) 37.375"




9B box dimensions.  Thank you Rex B for taking these as well as other pictures for me.






Looking for 400 specific information to understand what will and wont fit.  The colored arrows are specific info i was looking for.




Length of box: 6.5"  (Yellow)
Height from base to top of bed:  8-15/32 to top of "V".  (Purple)
Lead Screw to bottom of bed where QCGB mounts:  ~2"  (red)
The blue dim is lead screw from the bed.  Have not pinned that down yet but am darn sure it is the same for all 9" & 10" units.


Matthew


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## mjhenks

So i am convinced that any 9" or 10" will work.  I am pretty sure the 11" as well but have less evidence to back that up.  If i were looking at an 11" box i would want the seller to take the measurements from my last post.

The search for a proper box took about 5 weeks.  Of course there were a number of them that sold prior to me looking but as usual when you want it you cannot find it.  I resisted buying one with missing parts because the piece parts for these are crazy expensive.  

I ended up with this one from a 9B-17.






Overall it is in very good shape and included the input gears and drive shaft.  The drive shaft was a huge bonus.

The drive shaft is set up for a power apron.  (Has the key slot down the length)  I have a feeling that all QCGB drive shafts will have this.  The Logan 400 of course does not.  The seller had the power apron as well but i do not see the need for a power apron on a 9" lathe that is not used daily and did not want to spend another $150.  (Might as well just find a whole 9B.)

The parts arrived in good shape and my initial inspection showed that all was good.  No broken gears, everything turned and could be adjusted.  Great.  The only down side is that the ID plate is in poor shape.  It is readable but is a bit beat up.  Will repair that later too.

Next steps.  Tear it apart, clean, paint and start to figure out why it will not fit on the 400 as well as what i need to change or adapt to make it fit.

Matthew


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## AR1911

The casting number on the 9B box is on the inside, opposite the feed/speeds data plate. It's in big number, you can almost read it by feel. It's visible in one of Matt's photos above.  I don't recall the number LA1201? but it was the same on the 9B and on the 11" Powermatic.  That casting number should be an easy way to verify fitment.

I would reconsider that power apron. Power longitudinal feeds are much smoother and leave a uniform finish. Without the power apron you have to use the halfnuts. You will do better to preserve that precision for threading.
  Also, parting off goes much better with power crossfeed.  You have to prove it to yourself just like I did.   
   I would not have a lathe without power apron feeds.


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## stevecmo

+1 What Rex said.  ^^^


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## mjhenks

Thank you for the guidance.  I guess when using lathes at work (mind you i am not a machinist but an Engineer) i have never really used the power cross feed.  

Three people have told me to re-consider....  I guess i will have to play with the power cross feed and see.

Can you explain what you meant by "Without the power apron you have to use the halfnuts."?  Why would you use the halfnut more if you do not have power cross feed?  I am sure if i had taken one apart i might understand.


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## AR1911

mjhenks said:


> Can you explain what you meant by "Without the power apron you have to use the halfnuts."?  Why would you use the halfnut more if you do not have power cross feed?  I am sure if i had taken one apart i might understand.



Without power apron, you have two ways to move the cutter down the bed as it moves the cutter along the workpiece:

1 - crank it by hand, which leaves a non-uniform surface on all but the very shortest work
2 - Engage the halfnuts, which wears the leadscrew over time. It is also generally faster than an apron power feed.

If you have a power apron, that slot in the leadscrew drives a worm gear, which in turn drives the carriage longitudinally (or the cross-slide at 90 degrees) through the handwheel shaft and then to the rack. This is the 3rd option, which gives slower, uniform movement and does not use the threads of the lead screw.


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## mjhenks

I think i mentioned this already but i am catching up still on info for this part of the project.  I am farther along then what is show and am going back to document progress.

Next step is to take it all apart.  Goal is to clean and re-paint but also get to the casting all by itself so i can start fitting it to the bed without the extra 10 pounds of metal.




It came apart fairly easy.  The Selector knobs shaft did not want to come out of the selector body and getting the pin in the selector shaft (between the two selectors that keeps them separate) was a challenge but otherwise this was straight forward.  Since all the gears for the cluster are notched for a key it is easy to ID them while the gears for the selector have a the key integral to the gear.  Also all of the double gears are the same part #.  The Logan we site also has a cut-away of this to aid in re-assembly.  

http://www.lathe.com/gearbox.htm

Wear wise the gears are in great shape.  The selector shaft has play in the bushings as does the cluster shaft.  Anyone have any idea how much radial slop is allowable?




Here is that casting number. LA-1201.  Again this is from the 9B-17 with Power cross feed.




This is the ID plate.  Hard to tell from the picture but the red paint is faded and the upper right has been damaged.  It would not be possible to flatten it out, paint it and then sand off the top to bring the aluminum back and reveal the details.  (Like i did for the Logan 400 ID plates)  The other bummer is that Logan does not sell this ID plate.  They sell this one.  

http://store.lathe.com/lp1785b.html 




It is for the newer boxes and uses a different stud gear.  That is OK.  I have a plan in the works to make my own ID plate.  Will work on that later.

Matthew


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## Redlineman

:wavinghi:

Gonna have to make some more popcorn. Great stuff, Matt.


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## mjhenks

Thanks AR1911.  

That is what i was thinking but was not sure.  There must be some other mechanical gizmo that engages that slot but does not touch the screw.  Is it always engaged and the selector just engages the cross feed?

Something else to research.   

Of course the obvious questions is which aprons fit which machines?  Are the 9" & 10" different?:thinking:


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## stevecmo

Mathew,

Converting your non-powered apron to a powered version would be a major project and I doubt if it's doable.  It would be much easier to buy a different apron / saddle.......and then I'm not sure.

There are additional gears in the apron that power the apron and the cross slide.  There is a three position lever on the front of the apron - center position is neutral, up is X and down is Y.  If you take a look at Tony Griffith's site you can see the lever I'm talking about.  http://www.lathes.co.uk/logan/index.html

Sorry if Rex's and my posts mislead you to think you should convert your existing saddle.  Hope this helps.

Steve


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## mjhenks

Steve,

Thanks for the clarification.

FWIW I did not think my existing 400 saddle/apron could be converted.  Not without remaking the apron and alot of parts from scratch.  :lmao:

I bet though a saddle/apron from a 9B would fit right on there.  Not sure about a 10" though.  I suspect they are different.  

I am just not familiar with mechanism that engages the slot in the lead screw. I imagine it is some sort of rotating device that does not touch the lead screw thread but has a key to pick up the slot.  That rotational motion is then transmitted to the cross feed.  The three positions would then be forward, no motion and reverse which somehow engages the gears without damaging them.  Maybe the key is spring loaded and finds the slot as it comes around.  That would be better then trying to mesh gears.  but then how do you reverse the motion.  Has to be more complicated than that.

 Something else to learn.  

If i were to tackle this i would just buy one and mount it.  

Thanks.


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## AR1911

The lead screw passes through a worm gear at the bottom of the apron. The bore of the worm gear is smooth, with a key. It drives a spur gear,  which meshes with a movable gear above it that connects to the selector shaft. In the down position it meshes with the longitudinal drive gears.  Move the lever through neutral to the upper detent and the gear. Swings up to mesh with a gear on the cross feed. The lever at the bottom is the clutch to engage the feeds
   That's a little simplified )


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## stevecmo

Mathew,

Rex explained better than I could.  Here's some pic's of the inside of my apron that may help.








Hope that helps.

Steve


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## mjhenks

Rex, Steve.

That is VERY different than the 400.

Rex Wrote  "In the down position it meshes with the longitudinal drive gears.  Move  the lever through neutral to the upper detent and the gear. Swings up  to mesh with a gear on the cross feed. The lever at the bottom is the  clutch to engage the feeds"

The bottom position engages the longitudinal drive gears.  You mean the drive shaft, like what the half nut does?     
When you move up and engage the cross feed.  Is it one direction only?  Power in and manual out? 
The clutch then acts the same as neutral or the middle position?  It is not the half nut then.

Did i understand that right?

How does the power get up to the cross feed?  Is the screw different?  Wonder how different the saddle and cross feed assembly is then.

How different are the 9" from the 10"?  Any idea?

These are pictures of the 9B saddle that came off of the same Logan my QCGB came off of.  It could have been purchased for $150.  It is no longer available.  You can sort of see the parts.  Too bad on Ebay you cannot contact the buyer....






Matthew


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## mjhenks

The power cross feed is the side show.  Great stuff and should be documented.  Keep the info coming Rex, Steve and anyone else who can contribute.

Back to our main feature for a bit.  With the QCGB taken apart for cleaning i was able to investigate what fits and what does not.

Here is my hit list.
-  Box.  Where to drill and tap holes?  What dictates the proper alignment and can i use the 9B's position?
-  End Support.  Will the 9B-17 drive shaft work as is?
-  Bull gear to box drive train.  What is needed?
-  Drive shaft alignment.  What has to be done to tram the shaft to the bed.
-  Box clearance to the deck.  Will the change levers clear the deck?

I will tackle each of these one by one.

Matthew


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## mjhenks

Box Location.  Where do i drill the two dowel holes and three tapped holes?  

From looking at the 9B, it looks like the QCGB aligns at the end of the bed.  The problem is that it depends on if the head stocks are exactly the same and the stud gear is in the same location relative to the end of the bed.




The pictures below are from 9B's.  (First is unknown.  Second is of Rex's.)  Both pictures appear to have the QCGB mounted at the end of the bed.   (Note the removable cover that apears to extend over the bed)





One thing i notice though is it looks like the Stud Gear is extended out farther than what my 400 has.  (Mine is the 1st picture)  That would really change the location of the box.  What is that distance??






You can see below that when i did a mockup of the box and gear train that the box wants to be about .100" from the end of the bed using my short stud gear.  (BTW, i am using a 24 tooth stud gear with two 48's.  The 56 to the outside of the first (top) 48 is just along for the ride)





So, if i mounted the box at the end and used my shorter stud gear shaft then i would have to move the QCGB "Y" gear mount out and likely space the QCGB input gear out a little as well. 

 The real question then is how long is the 9B's stud gear shaft and if i did that were would the box want to be mounted??  

Matthew


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## AR1911

I'm confused. The bull gear is the largest diameter gear, right behind the chuck mount, to the right of the belt pulleys. It is only used for the back gears.
    You seem to be referring to the long gear at the other end of the spindle which send power through the geartrain.


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## AR1911

OK, let me try this again while we are looking at the back of my apron:



	

		
			
		

		
	
Upside down, sorry. I corrected it, but it reverts when I upload

Dead center is the worm drive. The internal key picks up rotation from the lead screw which passes though it. It also passes through the half-nuts, but they remain open.
This spins the gear at the top of this photo. It freewheels unless you engage the clutch. Then it drives a gear behind the worm which in turn drives the BIG gear in the lower part of this photo.
That gear is on a lever attached to the selector lever on the front. It swings down (toward the clutch) to pick up a gear that drives the shaft at the left side of this photo, which turns against the rack for longitudinal feed. 

Move the lever up and the gear moves up. In the above photo it is in the crossfeed position. You can see it sticks up above the top edge of the apron.
That big gear, when moved up via the feed lever, engages the gear on the crossfeed shaft, as seen in this photo of the carriage:




Hope that helps


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## mjhenks

Your confused.  Believe me, i am the one who is confused.  :whacky:

Stud gear.  That is what i meant.  I went back and corrected that.  

I believe the gear in red is the Stud gear.  If i have that wrong please correct me.  This is the gear though that apears to be sticking out farther on the 9B machines.




Matthew


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## AR1911

Alignment of box to bed.  I sent you this a few days ago via email. Note the overhang.




Here's what my stud gear looked like:


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## mjhenks

Rex,

Did not receive that first picture.  

I see there is quite the overhang of the box to the bed.  That picture is alot clearer than the dirty lathe picture i had.  The overhang along with the added length to the stud gear shaft would make alot of sense as far as why the box overhangs.

Can i get some details on your stud gear shaft?  
What does it look like as i think i need to make one.
What is the overhang of your box beyond the bed.

Another issue that this may solve is that the right side of the box hits the longitudinal rack.




I will cover this little discovery more later.

Matthew


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## mjhenks

Rex,

Understand the apron now.  The longitudinal motion is driving the hand wheel which is using the rack to move the saddle, not the lead screw.  That saves the half nut from needless use.  Got it.

How about forward & reverse?  Is it just one way on this model?  In and to the left?

I was playing with the power cross feed today on a larger lathe.  Facing off a nasty cast iron back plate to make into a usable piece.  (Thank you Henry BTW)  The power cross did make it nice and gave a nice finish despite the cast iron.

Matthew


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## AR1911

mjhenks said:


> How about forward & reverse?  Is it just one way on this model?  In and to the left?



That lever that the stud gear is mounted on? 
That reverses the leadscrew rotation, and thus changes the feed direction


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## mjhenks

That make sense.  Can you change that gear while the machine is running?  That would seam dangerous for the gears.

Matthew


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## AR1911

Nope, gotta stop the spindle. On mine you have to loosen a bolt to move the lever.


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## mjhenks

Next i looked at the drive shaft end support.  Could i use the stock 9B-17 lead screw and the 400 shaft support?

Mind you that what you see below is with the gear box mounted .100" inboard from the end of the bed.  In previous posts you will note that i do not think this is the right position for the box.  Any change in the box location will affect the end support.

I installed the axial collar on the lead screw in its original position for the 9B-17 using the witness marks left on the shaft from the collar set screw.  I then placed the lead screw into the box with the collar against the box.  I then installed the end support as shown.






The lead screw JUST makes it.  That is the bolts in the bed are usable but the lead screw is butted right up against the left side of the support.  You can also see alot of extra shaft out the right side of the support.  

This supports my previous thought that the gear box needs to move to the left once i figure out the stud gear situation.  It also further supports that the 9B is a very close cousin of the 400.  

No pictures but while fitting the lead screw into the end support i noticed a nice wear groove on that end of the shaft.  I think i will be OK though as the groove is about 1/2" wide and the support is about 1-1/2" long.  Plenty of support.

My conclusion is that the lead screw and end support are usable as is once i figure out the right spot for the box.  (Assuming the box is moving to the left)

Matthew


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## Redlineman

LEAD SCREW, Matthew;
Ya gotta talk the talk when ya walk the walk when you make it to the big leagues, dude!? :jester:

Never noticed the lock-down reversing setup on the 400. Wow... there's a place they saved a few beans over the 200.


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## Mister Ed

Matthew - Not sure if you have seen this write up or not?
http://lathe.com/ll-group-archive/adapting_a_qc_gearbox.html

I think Scott is talking more 10/11, so the measurements might change ... but the principles should be the same.

Also, look at the dial on the apron you did not buy. 

*AR1911* - Are those original dials on your lathe??? They look almost large enough to be readable!!


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## mjhenks

Big leagues.  Man i just want to stay in the minor leagues.  )

Sometimes i type faster then i think and proof reading is just not one of my strong points.

Thanks for keeping me honest.


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## AR1911

Mister Ed said:


> *AR1911* - Are those original dials on your lathe??? They look almost large enough to be readable!!



Yes, those are original. This is a 1962 model. I think the 1957 model 9B I used to own had smaller dials.

- - - Updated - - -

[FONT=century gothic,arial,helvetica]from the Logan page "the Gearbox from the 9"
Lathes are different, although the internal parts are mostly the same (the
Drive Shaft is different, as well as the box itself).[/FONT]"

I thought the 9 - 10- 11-inch lathes all used the LA1201 box?

My 9B and my 11" Powermatic use the same box.

Matt, are you seeing the leadscrew offset mentioned there?


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## mjhenks

The next part i had to check out was the clearance cut on the 9B bed behind the gear box.  What does it clear and do i need to add this?





Obviously it clears the gear box.  What i could not tell is what part of the gearbox.  It would either be the housing or the gears.  From the picture below you can see that the casting (Blue circle) sticks out father then the gears. (red circle)  To me, this means that the casting is what needs to be cleared, not the gears.




Looking at my set-up you can see that the casting clears the bed when the QCGB is aligned to where it mounts on the bed.  Given also that i expect the gear box to move out (towards the stud gear) i should be even farther away from hitting the bed.




My conclusion right now is that i do not need this cut.  If i had needed it i would have milled a pocket from the front of the bed with a radius tool instead of trying to stand and clamp the bed to an angle plate to replicate the original cut.  I also may have tried a right angle adapter on the mill as i really do like to replicate the original design but for now i think i can put this behind me.

A few post back, Mr. Ed brought up an article by Scott Logan talking about a 11/32" offset of the lead screw to the bed in the front to back orientation.  I had read that article but did not attach significance to it as i was using a 9" box.  

Right now i have noticed a slight difference in the horizontal plain of the lead screw compared to the bed but not front to back.  I will detail the horizontal findings in my next post and will confirm the 11/32" as well. If i find the 11/32" affect me then i may have to re-consider my conclusions in this update.  The article is talking more about 10" & 11" units and Scott does state that the 9" box is different.  Since we are talking about a 9" to 9" conversion here this may not apply. 

Stay tuned.

Matthew


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## Mister Ed

mjhenks said:


> A few post back, Mr. Ed brought up an article by Scott Logan talking about a 11/32" offset of the lead screw to the bed in the front to back orientation.  I had read that article but did not attach significance to it as i was using a 9" box.
> 
> Right now i have noticed a slight difference in the horizontal plain of the lead screw compared to the bed but not front to back.  I will detail the horizontal findings in my next post and will confirm the 11/32" as well. If i find the 11/32" affect me then i may have to re-consider my conclusions in this update.  The article is talking more about 10" & 11" units and Scott does state that the 9" box is different.  Since we are talking about a 9" to 9" conversion here this may not apply.
> 
> Stay tuned.
> 
> Matthew


May or may not apply, but keep it in mind. I was thinking of the article another way, it was talking about adapting a gearbox to a non gearbox machine ... albeit 10/11s. What I picked up, was that the non-power aprons (non-QCGB) have the halfnuts at a different elevation than the powered aprons (QCGB). 
So the question would be ... did they use the same logic when they designed the 9's? One clue might be to look at the parts diagrams for both versions and see if they had a different support bracket/bearing on the tailstock end of the leadscrew.

Again, I'm not sitting here saying I'm right, and you have the lathe in front of you .... I just like a good puzzle.:think1:


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## mjhenks

The next item i looked at was the lead screw alignment to the bed.  Recall that it appears that the box will mount up close to the end like the 9B and that once shifted for the stud gear the lead screw end support looked ok.

How does the lead screw tram to the bed?  Starting from the head stock moving to the tail stock with the saddle near the middle of the bed i looked at the distance from the bottom of the bed to the top of the lead screw.  Of course i am assuming that the bottom of the bed is relatively parallel to the top ways and that the lead screw is relatively straight and the same diameter.  I think these are reasonable assumptions.  



1.50" at headstock



1.50" at left side of saddle



1.45" at right side of saddle



1.40" at tail stock.

Note that the half nut nor the rack drive gear were engaged.  I rise .10" from the head stock to the tail stock.  Probably not good.

I also need to check out the front to back to the bed as well.  I have yet to do that.  I will re-take the measurements above at the same time to make sure i understand what i need to do in both axis.

Matthew


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## mjhenks

And now for the other direction.  How well does the lead screw align to the bed front to back.  

I again lined up the QCGB and shimed it in place with the lead screw installed.  This time i shifted the gear box like i expect to do when i get the stud gear info.  Interesting that the end of the lead screw once the box was shifted aligned perfectly with the end of the support.   Hmm.....

These pictures were hard to get.  What i did was align the scale to the front edge of the bed which is directly over the lead screw.  I sighted down the side of the bed's front edge and aligned the scale to that sighting.  Once i aligned the scale, my "V" block, which was against the lead screw and also aligned parallel to the bed edge gave me the measurement.  I then backed off to take a decent picture of the measurement.  Otherwise i could not focus on the edge and the scale at the same time.



Head stock is about .130"



Left side of saddle with saddle to the right is about .110"



Tail stock is about .100"

I would say that i do not have the 11/32" issue with this system.  I will reserve judgement though until i get my half nut installed.  I think the best way to figure out my alignment is going to be with the half nut engaged and more or less letting it set the lead screw where it should be.  It looks though like i am not too far off.

Can anyone measure for me your stud gear shaft?  Or the distance the stud gear stands off from the reversing lever mount surface and some good pictures of the spacer?  I am sure the design is the same, just farther out.  I suspect i need to make a shaft.







The next topic will be the height of the bed.  I am going to double post here as i am in catch-up mode right now with the projects documentation.

When i mounted the gear box before i took it apart i thought there was no way the selector levers would clear the deck.  So how high does the bed need to be?




My gear box as you can see just barley clears the table.  (Wish i had removed the towel for the picture.)





Measuring my Logan 400 the distance from the table to the "V" is ~6.8".  I am measuring to the front face transition to the "V" as that is the comparable measurement i have.




The same measurement on a 9B is about 8.2"


The logan 400 is about 1.4" lower than the 9B.  I do not know if the difference is in the risers or the bed.  Seems like they would have re-used the bed casting but i do not have any supporting data except that i need to raise up the Logan 400.  

I will do this by adding 1.5" square risers between the table and the lathe.

Matthew


----------



## AR1911

If you look at the photos you posted of you 400 and my 9B, it's plain the difference is in the risers. I'd bet the bed is the same.


----------



## mjhenks

*Lead Screw*
Did some more alignment work on the lead screw last night now that the half nut is installed.  I supported the lead screw with the half nut and then moved the saddle to the rear to see how well the lead screw naturally would align to the end support.  It aligned perfectly but i expected that.  I then did the same to the gear box.  Things did not line up so nice.  ( note that the half nut was near the part i wanted to test fit and the other end of the screw was supported by either the end support or gear box.  My theory is that the half nut would align things close enough to tell what was going on.)

Honestly it was hard to get a good picture or measurement.  I can say that the box needs to be milled to align to the shaft.  I think i will have to take baby steps when doing the work.  Here are a few pictures but take the measurements with a grain of salt.



From the front.  (i placed a socket into the bore to have another diameter to align to.)



from the bottom.

What bothered me is that i did this twice and both results were not the same.  Not even close.  Above are the closer of the two trials.



this was the first trial.  You can see the shaft is farther off.  I am not sure what to do with this right now.
*

Longitudinal rack.*  What is going on.  In post #25 i hinted of a problem there.  Now that i understand more where the box might end up i can look at what is needed here.

The rack for sure interferes.  This picture is with the box aligned to the left side of the bed.




Here is the box aligned where i think it will go.  I then placed a rack mount screw in the farthest left hole in the bed (red circle) and then aligned the rack against the box.  By rotating the rack you can see how far off the screw is to the hole. (blue circle)

  I need to remove about 5/8" from the rack and it will mount.  Easy mod.




*New part*






I think it is from a 10" logan but honestly the seller was not sure.  There are two styles out there.  This one seamed to have the right spacing between the gear and mount screw.  Could not tell how to get it apart to clean it but it was in great shape.  Re-painted it and installed it.

*How is it made?
*
My gear selector shaft is shot.  have to make a new one.  I figure the end cap is plug welded.  i am looking to internally thread it or similar.




Matthew


----------



## mjhenks

Rex  (or anyone with access to a 9B with gear box.)

Can you measure this for me?  Outside edge of the stud gear to the mount face on the reversing lever assembly.




The Logan 400 is 1.13"




For documentation and future reference I found this thread about installing a QCGB on a Logan 200.  He talks about the 11/32" mod
http://madmodder.net/index.php?topic=7917.0

Thanks


----------



## AR1911

??? = 1.660"
that spacer is .750"


----------



## mjhenks

Thank you Rex.  I have already started to make a new shaft.

I also received a replacement shaft for the gear box selector handles as well and start making that too.


----------



## mjhenks

*Final Gear Box Alignment*

Now that i know the length of the Stud Gear shaft i can locate the gear box along the bed.  I expect it to overhang the left edge of the bed and the left most mount hole to be near the end of the bed.





Setting the gear that the Stud gear interfaces with to 1.66" sets the gear box ~ .410" overhung from the end of the bed.  Right where i thought it would be.  These holes are now marked for drilling later.  I will not drill them until i get the lead screw aligned properly.

*Lead Screw Alignment to gear box.*

In previous posts i have shown that the lead screw does not align to the box.  The power apron from the 9B (as reported on the larger Logans) changes that location.  I will have to mill the box down but by how much?

I decided to try a new approach.  The half nut engages the lead screw but allows some radial play.  What if i grabbed the lead screw on the area that is not threaded.  That would center the shaft really well on the closing center of the half nut.  Assuming the OD of the lead screw is concentric with the thread center (which i think is fair) i could grab that part of the shaft to show where the gear box needs to be.  The other bonus is that i will be grabbing the shaft near the end which minimizes the overhang of the shaft.  Also i have the tail end of the shaft in its mount which i have already shown to be OK.  *Does this all sound fair to you guys?*





The center of the Lead screw from the bottom of the bed is 2.77"
The center of the lead screw to the face of the bed is .35"
Note that both measurements are to the mount surfaces for the box.

Now where is the input shaft location on the box?





The center of the Lead screw input bore from the top of the gear box is 1.85"
The center of the Lead screw input bore from the mount face of the gear box is .30"

That means i should have to remove from the mount surface of the gear box:
2.77" - 1.85" = .92" from the top.
.35 - .30 = .05 from the face.

I will baby step into this one.  Fortunately you can always shim back out.

*The change gear cover does not fit??*

Rex or any other 9B owner.  Can you take a few pictures of your cover as it closes down on the gear box?  Mine does not close so i am betting the red below is removed from the 9B.









I have these from an unknown owner and it looks like it is cut back.  I also see the hole in there.  Is that the grease the shaft just below the stud gear?  I have the change gear chart there.  Hm....  

*What is next?*

- Making a new stud gear shaft.
- Making a new gear selector shaft.
- Modify (shorten) the Rack.
- Make riser blocks.
- Drill & tap bed for box mounts.
- Mill box to align shaft.
- Rebuild gear box
- Mount it all
- Re-make the ID plate.

I see things to do for at least another month.


----------



## mjhenks

Some progress this AM.



Gear Box selector shaft.  Will put the key slot and pin hole in next week.  No plug welding.  Loc tite.



Stud gear extended shaft.  Have to put the key in next week.


----------



## Mister Ed

mjhenks said:


> *Final Gear Box Alignment*
> *Does this all sound fair to you guys?*


I got lost on the threaded/non threaded bit (I have a heck of a head cold and am not thinking clearly) ... but yes. Mounting the right side of the screw in its bearing and clamping the half nuts on the left side of the screw, should bring you in right close. I think I would put the half nuts right on the last bit of threads. Really at that point, only wear in the nuts could make a little difference. At least the way I am thinking.


----------



## mjhenks

As usual I could have been clearer....

What I meant was that I am betting that the OD of the non-threaded portion of the lead screw has the same centerline as the rest of the lead screw.  Grab and center on the non-threaded portion of the lead screw, use that to align things and it would be as good as trying to grab the thread with the half nut.

Matthew


----------



## mjhenks

Gear Box selector shaft is done.







Made the new 3/4" spacer for the stud gear and learned how to use a new tool.  Never have used a broach before.  I did not have the right size.  (5/32)  I made it 3/16 as it does not transmit load, only serves as a spacer.







Re-bushed the gear box housing.  Replaced the selector shaft and gear cluster shaft bushings.  Pressed them in, indicated the location of each and reamed to size.




Rebuilt both selector assemblies.  I opted to mill flats on the shaft and bushing that are set screwed in place.  Never understood why people set screw directly on a shaft.  Never comes apart easy and you are prone to spinning the shaft if it is transmitting torque.
I also re-painted the handles and knobs.  Turned out nice.  The only part i had trouble with is what way the gear goes.  The gear has a boss on one side.  That goes toward the side of the handle that has the wider width for the shaft to pass thru.













I also have finished the artwork for the new data plate and have the transfer film and new drive pins ready to go.  Have yet to get the sheet aluminum or acid.

Up next is to put the 5/32 key slot in the new stud gear shaft and make a corresponding key as well as get material for the risers i have to make.

I am also working to get a fixture rigged up to cut the gear box mount surface.  That is the next big step.  

It is kind of nice that i have gone from research to actually doing things.

Still looking for information on the gear cover clearance for the gear box.  Any measurements out there?

Thanks


----------



## Mister Ed

Really nice. What kind of mill do you have?


----------



## mjhenks

Grizzly G3102

Had a mini mill.  Sold it to get the grizzly

The picture above was done at another shop.  That one is a Bridgeport.  Can't fit one of those in the garage...


----------



## mjhenks

Last night i tackled the gear box mount surface.  What a pain to align.

My guide was this web site.
http://madmodder.net/index.php?topic=7917.0

After borrowing some adjustable stands and finding suitable clamps i began to align.  About an hour later i had the average readings all under .001".  I say average as the surfaces themselves were not very flat to begin with.  I took this as assurance that i did not have to hit the alignment dead on.

I noticed a calculation error in one of my previous posts.  I added 1" to one of my measurements.  So the .920" material removal should have been .08".  Good thing i found that before i cut.

I overcut both surfaces a little so i did not have to re-align on the mill and instead plan to shim on the lathe.  A test fit after milling show that i am about .010" off in both directions which is what i wanted.  Will start shimming out and then mark and drill the holes.




I also finished the new key for the new stud shaft.  Hope to have the shaft done tomorrow.


----------



## Mister Ed

mjhenks said:


> Grizzly G3102
> 
> Had a mini mill.  Sold it to get the grizzly
> 
> The picture above was done at another shop.  That one is a Bridgeport.  Can't fit one of those in the garage...


Ahhh ... I thought you had said you had a smaller mill, then I saw the pic and went hmmmm. However that Clausing clone Grizzly is nice looking too. I'm looking for something to replace my mill/drill ... just have not found the right one yet. I would really like a MillRite.


----------



## mjhenks

Wish i could have fit a bridgeport.  Was offered one for $500.  The mini-mill was good for softer materials but needs updates or a patient machinist for anything beyond that with accuracy.  I did make a DRO for it and that made a huge difference.

The Grizzly was an opportunity that i could not pass up.  Sold one to buy the other and it fits well in my garage.  What a challenge to move.  I like the knee alot.  It has a DRO but still is a bit wiggly.  Better than the mini-mill thought.  

I use the bridgeport when i can.   Otherwise i am happy with the grizzly for what it is.


----------



## mjhenks

Designed this a few weeks back.  Artwork for the new ID plate i plan to etch.  It was fun.  The only part that is not spot on is the "Logan" font.  Did the best i could to match it but even the new one is different from the original.  I'm OK with that.



Original Tag.  Hard to tell but the upper right is damaged and being curved it would be really hard to re-paint.



What Logan sells.  This is for newer boxes with a different gear set.



New artwork.


----------



## mjhenks

Finished the stud gear shaft and put it all together.  







Test fit the gear box last night with some shims and it looks like i am .015" out in both directions.  Will be making some shims tonight.


----------



## mjhenks

Reversing assembly is now installed.  Perfect fit.  Red circle is the new stud shaft and spacer.  The spacer is now 3/4" instead of the original 1/4".  Also the gear box is now properly placed with the overhang from the bed shown in blue.  The mount holes are transferred and my shims sizes are calculated.  




Now that the box and gear assembly are located I went back and looked at the gear cover again.  The cover is now identified as yet another piece that is different.  

Notice the left picture below (my lathe) that the upper part of the cover is in line with the lower.  I spaced my cover off by moving the mount on the bed so that the cover aligned with the filler that bolts to the side of the box to protect FOD from getting into the cover.  

When I did that I noticed the gap at the upper drive gear as shown below left.  Now look at the right picture.  Notice that the upper part of the cover sticks out farther then the bottom.  They are different. Even the profile is different.  The angle at the top starts higher up.  This along with the hole identified earlier and the clearance at the bottom for the box mean I am not going to be able to modify mine.






Another part to look for but I do not think it is critical right now.


----------



## mjhenks

The gear box is mounted.  Shims worked great and the lead screw lines up perfectly.  Woo-hoo.:thumbzup3:

Details.

I made my shims today and drilled the holes in them.  The front shim was .035" and the bottom .010".  I sandwiched the front shims between some aluminum and drilled them out to the perfect size and location by clamping them to the gear box and chasing the holes right thru the gear box holes.  Perfect match.

I then placed the gear box on the bed and transfer punched the mount holes.  Drilled and tapped the mount holes for 5/16-18 screws next.  Mounted the box with its screws using my 1/4" drill bit and transfer punches to align the shims to the box.  Once tight I then drilled the dowel holes 1/16" undersize and then chased the hole with a 1/4" reamer.  Perfect match.

The gear box finally has its first coat of paint on it and I can start to look toward putting the gear box back together.  







I also finally mounted the longitudinal rack.  If you recall I had to cut it short to clear the gear box.  It is mounted and I was able to then mount my apron handle.

I did some more looking at the left side cover and am now wondering if in fact the bottom is actually cut back instead of the top being casted forward.  The reason I looked is that the hinge for the cover is WAY off the end of the bed in order to line up.  Hmm....  :thinking:    

I may need some more measurements Rex.


----------



## mjhenks

Finish fly cutting, drilling holes and chamfering the edges of my riser blocks today.  Also mounted them.  I must say, being a tall guy it is nice to have the lathe a little higher.  Have to find longer mount bolts but that is OK.





Was going to try my hand at etching today.  Bought the Hydrochloric acid, hydrogen peroxide, gloves and container.  Figured out how to mirror my artwork, printed a sample and.....  Had to stop.  The resolution of my printer is just not enough for the small text.  I have a 600dpi laser.  Going to have to figure out some better way to print on to the pnp-blue transfer paper.  Weird thing is that the resolution seemed fine till I mirrored it.  Will play with it and see what I can figure out.  :think1:



Also got the second coat of paint on the gear box today.  I can see the end in site.  Lets hope it's not a freight train.


----------



## stevecmo

Looks like you're closing in on it.  Great job!

You might try one of the copy places.  They may have a high res printer.


----------



## mjhenks

:banghead:......

Gear box together.  Does not turn.....

Will take apart Tuesday and see what I can see.  I suspect the gear cluster shaft is binding.  It was tough to install.


----------



## AR1911

mjhenks said:


> I may need some more measurements Rex.



Sorry Matt, I get out to the shop and then get immersed in a project. I'll try to get some info today or tomorrow.


----------



## mjhenks

Rex

Whatever you can get.  At this point I do not think a mofification will work but would like to confirm.

Thanks


----------



## mjhenks

Got the box back apart.  The gear cluster shaft does not align well side to side.  It binds once you engage the opposite side bushing.  

If you recall i indicated in each side to ream them.  Apparently they did not align with each other.  (I do not have a reamer long enough nor a boring bar that small that long. )  I figured the castings were likely bored in line and the bushings would follow.  Wrong.

Likely my only play is to polish down one end of the shaft to aid the fit.  Not the best solution but it will not affect what the box is suposed to do.  Might wear faster.

I am open to other ideas.


----------



## Redlineman

Hmmm..

I have hand fit plain bearings before.

More study. My gut tells me that since these were more or less budget priced machines, they were tossed together very quickly back in the day. There were no fancy time consuming techniques brought to bear. This is not to say that they were not a fine machine for the price - at least as good as any of their "more legendary" competition - but really... they just banged them out. So... there must be a simple explanation based on a simple process, based on the notion that these were very quickly rendered machines.

This gets me thinking of the early -vs late Model 200 countershaft arrangement. Was the early "floating bushing carrier" arrangement conceived to combat line bore issues? Was the subsequent solid countershaft bracket successful because it was line bored/reamed?

I'm wondering about the bushing land and the tolerances of what you pressed in. Is it possible that you simply do not have enough, or is it actually a misalignment?

Forgive my rambling. My pre-dinner bourbon has addled my brain....


----------



## mjhenks

Pre-dinner Bourbon hey.  I follow what you are saying.  

I purchased the bushings from McMaster Carr figuring they would  work out.  Actually hoped i did not have to ream but no way the shafts  were going in without.

The press was decent but not alot reamed out.  They were indicated to .0002" before reaming and of course when indicating them in they were perfectly round but not off by much X vs Y.  

The selector handle shaft (5/8") was also repaired the same way.  It works and fit nicely.

When i push the shaft in from either side it fits, slides and rotates nicely.  As soon as you hit the opposite bushing it locks up.  From both directions you are able to push it through but then it will not rotate.  I think it would be quite hard to measure the offset but then again i do not look forward to reducing the diameter at one end of the shaft either.


----------



## mjhenks

Problem solved

I realized I was sliding the shaft in from the same direction each time.  The end with the key slot.  When I turned it around and tried the other end the shaft would not even start into the bushing.  After micing both ends I figured out that the one side was  larger and that is what was binding.  Once turned and polished the shaft installed and spun quiet nice.


----------



## Mister Ed

Redlineman said:


> Hmmm..
> So... there must be a simple explanation based on a simple process...



Glad to hear you figured out the simple solution.:thumbsup2:


----------



## AR1911

OK, Matt, here's some photos. Some are "Worm's eye" view.
Hope it helps


----------



## mjhenks

Thank you Rex.  Confirms what i suspected in that the cover is different and without either giving up on it looking right or major surgery it would not adapt very well.  Have to think about what to do.


----------



## mjhenks

With my shaft fit solved it is time to put the gear box together.  Here is how you do it.  I will leave out details like lubricating each part and basic alignment and step thru just the basics.

This link will help alot with your parts.

http://www.lathe.com/gearbox.htm

First step is the input shaft assembly.  One shaft, two gears, one spacer, one key and one clip.  Note that the gears are both stepped but one is keyed and the other bushed.  The keyed gear is first.  The spacer and clip go on the end to secure it all.






Next is the gear cluster shaft.  Two sides to this one.  Left side first meaning the side the input shaft is on.  The build is from that side.

One shaft & three gears.  All three gears are bushed and two of them are identical stepped.  In fact they are the same as the bushed stepped gear from the input shaft.

Slide the shaft into the housing with the keyed end first.  First the small gear and then both stepped gears.  Do not leave any shaft sticking out of the last gear.





Now the right side.  This is the trickiest part of the build.  9 gears, one key and one spacer.  Note that all the gears are keyed as well as the spacer.  




First step is to orient your key.  You should have a witness mark on the key from the set screw in the spacer.  That is the side that goes into the slots in all the parts.  Test fit your key into each part.  

Place your gears out in order from smallest to largest.  (reference the link above for more detail)  Note that the largest gear has chamfers on the sides of the teeth and that you will have two of one of the gear sizes.  Of those two identical gears, one of the them goes on the far end next to the largest gear and the other is in line with the rest of the gears. 

Take one gear, place the key into the gear and find a rod that will go into the space that is left and is long enough for the entire gear/spacer stack.  an X-acto knife handle works great.  Place the key into the spacer and over the handle and start putting each gear in line.  Don't worry too much if they do not seat.  You are trying to get them in line and basically oriented.




Pull the handle out and now be careful with the stack to maintain alignment.  Place the stack it into the housing.  Mine was a VERY tight fit axially so i had to tap it carefully in place.  Make sure you know where the key is and where the slot is in your shaft.  Align them the best you can.




Now start tapping the end of the shaft into the housing.  As you hit each gear, finesse it into alignment so the gear engages the key.  It is actually pretty easy as once you get the key into the first gear and as long as the gears are sort of still engaged into the key the shaft self aligns.  Watch the key to make sure it does not migrate down the shaft.  If it does and enters the far bushing then the system will lock up.  Tap the key back down the shaft and continue the alignment.




Once complete test that it turns freely.  (This is where i figured out i had the sticking shaft.  Had to take it all apart)
Note that the left side and right side will not spin together.    Once you are happy then lock the set screw in the spacer. 

Next is the selector gears.  One shaft, two gear assemblies, two small gears, one collar and one pin.  Pretty straight forward.  

The only thing to note is the orientation of each selector handle.  Note that one side is wider than the other where the shaft passes thru.  The wide parts go toward the outside.  Make sure the handles slide left to right nicely as this is what you will have to move to select your gears.  The small gear is placed inside the bore as you pass the shaft thru.  You have to align both the bore and the key.  Once you are done, secure the end with the collar and drive the splitting pin thru the hole midway along the shaft.  (That keeps the left handle on the left side)  Again check for smooth operation.




Last step is the lead screw.  One screw, one spacer, one key and one nut.  See left side of picture below.  Make sure the gear only touches the far left gear.  You now see why the largest gear has chamfers on it.  Easy.




Done.  Re-check operation and get ready to install.  

You should still have parts.  The left side input gear, one spacer, and one nut as well as the left side gear assembly. (Banjo i think it is known as)  You also should have the parts to mount the box.    Note that if you took out the alignment pins in the box to re-install those at this time.

That is how you put a box back together.  You will note that my box is also still missing the ID plate.  I will install that later.


----------



## AR1911

Matt, I must be missing something. Your gear cover looks just like mine.
What difference are you seeing?


----------



## mjhenks

Rex

If you look at your second picture. You will see that the top edge of the cover near the back side of the spindle covers that whole area.  You will also see the edge that mates with the removable guard on the QCGB also covers it's area.

Now notice that those two edges are not on the same plane.  The top one is farther out by about 3/4".

Mine are co-planer and therefor when I align to the gear box cover I have a gap at the spindle.  See red circle below.




Make sense??

Can't just cut mine back because then I would hit the gears.  I would have to weld a new lip up top.

Other differences are mine has four small holes to moving the gear chart and yours will have one hole to grease the gear train.  Both have the hole for material thru the spindle.


----------



## mjhenks

So I've had it.  I am tired of this project.  I just give up.   :whiteflag:

The project is just too much to handle.  I knew I was over my head but stubborn me.....  I cannot finish it to my standards.  Sorry to waste your time.  

 Just so the lathe does not sit in pieces forever I decided to hire a journeyman to finish the job.  He is just learning but was highly recommended and works cheap.  We will see if I made the right choice.













Can't help but wonder if I had any of you for at least a second.  My oldest son spend some time with me last night in the garage as I mounted the gear box. He is shown tapping in the input shaft woodruff key.   He does work cheap and is rather inexperienced but no, I did not give up.  )






It is mounted and get this....... It even works.   Had to take it off and on a few times as I would forget this or that as we went along but after about 30 minutes we got it mounted properly.




The gear train aligned pretty well.  Looks like I am about 1/16" too far inboard with the box location but the gear train has adjustment.  We lubed it all up and flipped the switch.  We did that systematic wise first keeping the box disengaged and slowly working our way to the point where the lead screw was spinning.  All went well.  Then the real moment when I flipped the halfnut lever.  Wala.....  Motion.  Awesome......  Then even better I changed speeds in like 10 seconds.  Oh man.  That is why I did this.  Totally Awesome.

Of course then I went and crashed it....  Without a chuck on the spindle the distance you can drive into the headstock is deceiving.  I ran out of thread on the lead screw and WHAM!!!!  All is OK.  Installed the chuck and figured I would hit that long before in real life.

A gift showed up.  Thank you.....




Started working again on the ID plate.  Hvontres was helping me with the artwork and got the image to mirror without loosing resolution.  Below is my first try at transferring the image.  You can see that the transfer was OK.  Debris is tough to keep off of the pieces.  That is why some of it did not transfer. 

 Not shown but my second attempt was better but still had issues.





I will likely still etch these two today to start to learn that part as well.

Oh, did I forget to say that I actually cut chips last night.  Just a few light passes on some 303 but still, cut chips non-the-less......


----------



## Mister Ed

mjhenks said:


> Can't help but wonder if I had any of you for at least a second.  My oldest son spend some time with me last night in the garage as I mounted the gear box. He is shown tapping in the input shaft woodruff key.   He does work cheap and is rather inexperienced but no, I did not give up.  )



Yes you did. I was reading from email and could not see the pic (and did not read past the first couple lines before clicking on the link).

Once I saw the pic ... I had a chuckle.


----------



## mjhenks

Playing with Acid this AM.

Boil & bubble.  Tested out both of the samples I did to see how much time in the acid.  20 minutes seemed to be the right number.

Cooking




After being etched.  The blue is the mask.




After the mask is removed you can see the depth and definition.




Painted.  What do you think??




I am encouraged.  I also etched a piece of brass as well.

What have I learned...
- etch a little longer
- clean everything to get a good transfer
- sand with 220 first and then switch to 360 grit
- This is also totally awesome.  I see some cool things you can do with this.


----------



## John Hasler

mjhenks said:


> Playing with Acid this AM.
> 
> Boil & bubble.  Tested out both of the samples I did to see how much time in the acid.  20 minutes seemed to be the right number.
> 
> Cooking
> 
> View attachment 74879
> 
> 
> After being etched.  The blue is the mask.
> 
> View attachment 74880
> 
> 
> After the mask is removed you can see the depth and definition.
> 
> View attachment 74881
> 
> 
> Painted.  What do you think??
> 
> View attachment 74882
> 
> 
> I am encouraged.  I also etched a piece of brass as well.
> 
> What have I learned...
> - etch a little longer
> - clean everything to get a good transfer
> - sand with 220 first and then switch to 360 grit
> - This is also totally awesome.  I see some cool things you can do with this.



Beautiful.  You need to make a plate for Bill to put on his TCG.


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## AR1911

Ok Matt, more info required.  Where did you learn that process?


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## Mister Ed

AR1911 said:


> Ok Matt, more info required.  Where did you learn that process?




I think this deserves an entire new thread!!


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## mjhenks

No new thread for me thank you.     And here I thought I had been giving too much detail...

It is already detailed in the link below.

http://www.instructables.com/id/How-to-etch-aluminum-panel-labelsdesigns-with-a-r/

 I was trying to figure out how I was going to replace my ID plate.  Did some research and came up with that link.  It is similar to what they do for PCB's.

The cost for the chemicals, gloves and container was about $20.  The artwork as you have read, was a challenge getting to mirror and keep its resolution.  Transferring is also a challenge.

My etching of the brass went OK.  I have to figure out how to keep it in the acid longer without the mask coming off.  I want to etch deeper.  Likely I will add more acid.


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## mjhenks

More Acid testing.  )

Ran a few more tests.  Transfer tests, painting test, sanding tests and rolling tests.  Good results.





First two I will call patina Id plates.  The transfers were not the best and the etching not deep enough but once painted they kind of pull of a decent new-used look for the guy who does not have a restored lathe but is missing or cannot recover his old plate.  The one on the left is also rolled.  Contour matched pretty darn good.  

As a side note, the original ID plates are bent, not rolled.  The curve is made thru 16 or 17 bends in the sheet metal about .2" apart.  You can see it from the back side.  (Bet you did not realize that)  I just used a sheet metal roller.  :thumbzup:




How about Brass??  Looks good.  I was going to two tone paint it but the etch depth is much too shallow.  This had 20 minutes in the 2:1 solution.  Would have needed another 40 minutes to get something usable.  Looks classy though.  The older QCGB's have a brass ID plate I think.





The good stuff is above.  Not finished but....

So I got tired of bad transfers, shallow etching and the mask starting to come off after 20 minutes in the bath.  What to do.  Research and experiment of course.  

After reading up on transfer issues I realized that this stuff is meant for copper and most of the suggestions were polar opposite to each other.  High heat vs. lower heat.  Longer press time vs. shorter press time.  yada, yada, yada.....  I finally figured I was on my own but I had a few things to try.

What you see above was made by ironing the transfer on high "cotton" heat for 5 minutes with a T-shirt between the transfer and the iron.  After 5 minutes I removed the T-shirt and went over the transfer with the tip of the iron and high pressure to get some good heat and direct pressure.  I then replaced the T-shirt and ironed another 5 minutes.  This was all done with a timer.  When done I stuck it in the fridge for 30+ minutes.  

I then carefully removed the tape holding down the transfer and carefully lifted the edges with my x-acto knife.  It came off really clean and I immediately noticed that the color of the transfer was way different.  A very dark royal blue instead of sky blue.  Hmmmm.....  :makingdecision:

Into the Acid bath.  I increased the Muriatic acid to 1:1.  Be careful.....  The plate started bubbling right away this time.  Could tell things were different.  I also immediately got some brown residue floating in the acid.  Still do not know what that was and it had me concerned.  I let it etch for 30 minutes checking every 5 and what a difference.  The etching is about .6mm deep and very well defined.  

You can see I have it painted and will sand it off tomorrow.  I have high hopes.....

I also wonder if I can repeat it.  Stay tuned.  I also think I am going to have to make a new thread showing how this is done once I gain confidence.....

Anyone need a new, used looking ID plate?


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## mjhenks

No picture but i was able to finish the ID plate from the above post.  It came out really good as far as resolution and definition.  I did not clean my sand paper enough nor did i wait long enough for the paint to be totally dry so i got some build up in the bottom left corner of residue.  Actually, it looks like patina.  I will probably use this one for the lathe.

I started playing with the gear box and the threading dial.  Never have used one so why not.  My belief is that you wait till the dial gets to the same number for each pass and engage the half nut there.  Did some playing.




Turned out OK but i have a hick-up in my threading.  I noticed that every once in a while i would see the chips momentary stop while i was cleaning up the aluminum diameter.  When i was threading you could really see the pause.

I think i traced it to my sloppy apron rack & pinion system.  This will probably end up in the other thread but i did not re-bush either bores in the apron for the two rack & pinion shafts. I should have.  Not sure the condition of the actual shafts either at this point.  I also do not know how well the pinion gear should engage the rack.  

Basically, each time the handle comes over the top if flops and again as it goes through the bottom.  That is causing to half nut to momentarily jump on the nut.  This also may be an indicator that my half nut is worn out.

What do you guys think?


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## Bill C.

mjhenks said:


> So i am convinced that any 9" or 10" will work.  I am pretty sure the 11" as well but have less evidence to back that up.  If i were looking at an 11" box i would want the seller to take the measurements from my last post.
> 
> The search for a proper box took about 5 weeks.  Of course there were a number of them that sold prior to me looking but as usual when you want it you cannot find it.  I resisted buying one with missing parts because the piece parts for these are crazy expensive.
> 
> I ended up with this one from a 9B-17.
> 
> View attachment 72990
> View attachment 72991
> View attachment 72989
> 
> 
> Overall it is in very good shape and included the input gears and drive shaft.  The drive shaft was a huge bonus.
> 
> The drive shaft is set up for a power apron.  (Has the key slot down the length)  I have a feeling that all QCGB drive shafts will have this.  The Logan 400 of course does not.  The seller had the power apron as well but i do not see the need for a power apron on a 9" lathe that is not used daily and did not want to spend another $150.  (Might as well just find a whole 9B.)
> 
> The parts arrived in good shape and my initial inspection showed that all was good.  No broken gears, everything turned and could be adjusted.  Great.  The only down side is that the ID plate is in poor shape.  It is readable but is a bit beat up.  Will repair that later too.
> 
> Next steps.  Tear it apart, clean, paint and start to figure out why it will not fit on the 400 as well as what i need to change or adapt to make it fit.
> 
> Matthew



Sounds like you are off to a good start.  Keep us updated on your progress.


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## mjhenks

No pictures but i tried to make another gear box label over the weekend.  I am certain on how to apply the mask now in that you  MUST apply the iron directly to the transfer material for at least 1 minute with moderate pressure.

I did 30 minutes again in the 1:1 acid mix but this time the etching came out really wide.  Almost like it the part is out of focus.  Will post pictures soon.


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## mjhenks

Ever get to a point in a project where you think it is just time to be done....  (Yes i stole this from my other thread.)

I am there.

 All that was left for the QCGB was the ID Tag.  Here is the whole lathe and the last steps for the ID tag.







I mounted the ID plate last night even though it is not as nice as i would like it to be.  Limited time means i will have to accept the tag as it is.

Took the home made ID plate for the Quick Change Gear Box, mated it to the old one and drilled the mount holes.









The rivets i used.  Lifetime supply




Mounted and looking pretty.




That should be all for the gear box.

 I have used it and love it.  Makes me think about the things i could do in minutes instead of hours with having to change the gears.

To be fair i am still missing the gear cover from a 9B to cover the left side where the change gears would be.  I have not located one and am not sure i ever will.   *(Have one you want to sell????)*

Overall a fun project.
 I am fairly confidant that all the info you would ever need is documented here and likely it could be easily adapted to any Logan lathe that needed a QCGB.

Matthew


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## JimDawson

Great job! Looks beautiful.


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## AR1911

mjhenks said:


> To be fair i am still missing the gear cover from a 9B to cover the left side where the change gears would be.  I have not located one and am not sure i ever will.   *(Have one you want to sell????)*



Matt, have you checked with Joe Bergamo at Plaza Machinery? I just bought a 9B spindle from him, and he's looking for other Logan parts for me.


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## mjhenks

So i was using the lathe last night to make some simple cuts.  Reminded myself that i really need to adjust the rack & pinion on the apron.  Anyways....engaged the half nut.  About a second later the gear train audible started to stall as if winding up.  Did not sound good.  By the time i got the motor turned off i heard a big pop and snap.  ummmm......  What just happened i asked myself.

I pulled the two levers on the gear box do disengage the gears.  hand spun the spindle.  All was OK.  Turned the lathe back on.  All was OK.  Gear train on the back side of the head stock seemed ok.  Problem in the QCGB.  Went back to my work as i needed to get done and did not want to look at what happened in the gear box.

I am afraid i have some repair work to do that i really do not have time for......

Will post what i find when i get into it.

Matthew


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## mjhenks

Ok.  Did some diagnostics tonight.  Need some help.

Gear box installed and set to lowest feed rate.  When i engage the half nut it runs fine but has a slight stressed sound to it.  BTW, i loosened the half nut and re-aligned it to the screw.  Just to be sure.

As i speed up the feed (by selecting different gears) the stressed sound get more intense and the lathe starts to bog down.  I do not dare run it for more than a second.

The spindle and the saddle are smooth and run fine.

I pulled the gear box out.  

With the selector handles disengaged i tested:

Spin the input side by itself it spins fine and smooth.  All the gears turn nice and slow down as you move farther down the stack like it should.
Spin the output side by itself and it spins fine and smooth.  All the gears turn together as they should.
Spin the shaft on the handles.  They spin fine and smooth.
Spin the input side and engage the left side selector handle and it still spins fine and smooth.
Spin the output side and engage the right side selector handle and it still spins fine and smooth.

Engage both selector handles and it binds up.  No matter what gear you select the system is not smooth at all.  Feels bound up.

I confirmed i have no broken gears and everything seems to be smooth and fine.  

Help....:whiteflag:

Matthew


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## JimDawson

I have never seen the inside of a Logan gear box.  Can you post a picture?  It sounds like there is a shaft dragging in a bushing or a bearing.  Do the two cluster gear sets spin independently of each other, or are they trying to spin together?


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## wa5cab

With the QC and half nuts disengaged, can you turn the lead screw freely?  The tailstock end bearing or bushing (whatever type it is) could be seized.

Robert D.


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## Redlineman

Matthew;

I must preface this by saying I really have no idea how the gearbox works. I stared at the pics of it upside down to see at least what it all looks like, but I still have no real understanding of what activates what, and I'm not experienced and/or smart enough to intuit its function just from staring at it. I don't even know what the parts are called. Assuming that the problem is internal to the gearbox, and having said all that;

My gut reaction is that there is a fundamental misalignment between the selector shaft (the shaft the handles are on) and the gear shaft (the shaft the change gears are on). When both handles are engaged, this creates opposition, where it does not with only one. 

I can think of a few reasons for a shaft or gear sets to bind. One would be they are not running parallel. Two might be that the tolerances of the end bushings are actually TOO TIGHT, and do not allow the gears to seek their natural, comfortable angle to each other. A third might be that the tooth overlap of the gears is actually too high. These teeth are not designed to run against the valleys of their mates. It seems like you might be able to have one or some combination of all of these going on.

I reiterate that I don't know squat about this stuff. I only hope that my wandering may trigger a thought or observation that brings positive results.


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## mjhenks

Thank you guys.  I spent some quality time with the lathe today and made some progress and some understanding.

Jim.  I had the box back on before i saw your request so sorry no picture from the back side.  I do have pictures in this thread of me rebuilding the box though that should the gear train.

Robert.  With everything disengaged all spins freely but that is what lead me to figure out part of the problem.

So while the unit was on the bench and the lead screw was not end supported i noted that things would bind up so i know the lead screw alignment is affecting things.  I mounted the box up and left the lead screw end support loose.   I then ran the lathe and engage the half nut and found it would run better.  So, first problem was alignment of the lead screw.  I moved the saddle all the way to the head stock and engage the half nut. I then locked down the end support.  A few tests showed that things were running alot better.  

I also again re-did the alignment of the half nut.  Problem 1 & 2 taken care of.  Old fashioned careful alignment.  

As i went through and tested the gears things were fine until i went to gear A and B.  When i get below ~22TPI things just go south.  The motor bogs down and the belt slips.  After re-alignment and testing i have come to the conclusion that the motor is just not strong enough below 22TPI.  The B gear goes up to 28TPI.  22-28 things are OK but i bet if i add the load of actually cutting material it will bog down.  My conclusion right now is the little Logan 400 just does not have enough Umph to use the A or B gears.  I will avoid that for the time being.  That limits what threads i can cut but honestly i will use the power feed for cutting OD's more that threads.  I will overcome the finer thread issues when i need to later on.  

Now, i did not try going into the back gears which gives more torque.  I will try that but still think the motor will bog down.  

The other curios things i have is the half nut really needs to be pushed open with moderate force sometimes.  Like it is sticking.  Not sure if that is a wear in thing or not.  Can't tell yet if it is a certain part of the lead screw (local screw wear) or something else.  Do not think it is alignment.  Interesting.  I was used to a floppy half nut before the rebuild but this really feels like it is grabbing or being pulled in as you try and open it up.

Big picture is i am looking high and low for a Logan 9B-17 apron and saddle for power cross feed so i will likely not dig too much into it.

I am also looking for the nut that keeps the main apron handle on.  I managed to loose that.

Scary thing happened today too while my middle son was watching me.  All of the sudden parts flew off the chuck.  Scared me.  Glad my head was not over the chuck as two of the jaws went flying....   :talktogod:  Thank you lord.  One hit the wall and the other flew across the room.  I did not realize the chuck was that far open as i never do anything that big.  Otherwise it was opening up on its own as i had nothing chucked.  That may be the case as i just rebuilt it and it is really smooth.  With the constant start and stop the inner gear may have been turning as i started and stopped.

Long post but i feel i made some progress and understand what is going on.

Matthew


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## Redlineman

This is very good factual, archival information you have added here. Very helpful to others on the path!

:thumbzup3:


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## mjhenks

JimDawson.

Here are a few pictures of the inside of the gear box i located.  The last one is all the parts layed out before restoration.










Matthew


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