# Repair/Restore Logan 820 lathe



## vincent52100

Finally got my lathe into the basement. I’ve started cleaning and reassembling it. I have found the problems with the gearbox. When I got it both gears on one lever were missing. I think someone crashed it. There are two bad gears in the gearbox. Can someone tell me how to remove the lead screw from the gearbox. I’ve removed the set screw from the collar but don’t want to break something trying to separate it. The S/N is 33206


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## wa5cab

I could be off in left field with this suggestion as I've never run a Logan.  But on an Atlas, you move the carriage up or down the bed until the half nuts are approximately in the center of the lead screw, close the half nuts, and either remove the right lead screw bearing or at least remove the bolts holding it to the side of the bed.  Then you use the carriage feed handwheel to walk the lead screw out of the GB.  If it takes more force than you feel safe in applying to the handwheel, rig up something to pull on the right end of the lead screw while turning the handwheel.  This should walk the lead screw out of the GB.  Then open the half nuts and extract the lead screw.


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## Chuck K

You need to remove the nut on the end of the lead screw, remove the gear and key, and it will pull out.  It's a lot easier if you remove the gb and screw as an assembly and seperate them on the bench.


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## vincent52100

Thanks! I have the assembly on the bench. I’ll get them apart and see how much damage is done. I can see four gears are bad or missing. Hopefully that’s all.


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## vincent52100

Started work on my gearbox this evening. It looks like I will need five gears. I’ve taken some pictures of the bad gears.
I’m not sure if I have the numbers right but I tried to make a list of the gear numbers.

Gears on lever
LP1014 (LP1300) 40T
LP1016 (LP1131) 22T
Gear Box
LP1002 (LP1137) 32/16T

The serial number is 33206 (Model year 1945?)

I’m hoping that I will be able to find the parts used. The rest of the gears look pretty good. I haven’t cleaned them yet but I don’t see any nicks etc. The same is true of all the other gears. 
Does it look like I’ve got the right numbers?
I’ve also put in some pics of the other gears.
Thanks for the help.


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## Holescreek

Logan was able to sell a nice lathe for a low price because the majority of the non-cast iron parts were available off the shelf from other suppliers. The gears came from Boston gear.   Once you get the dimensions of your gears (DP, ID and width) find the matching Boston Gear part number then search for them Amazon and MROsupply. You will likely find brand new gears for the price of used.


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## vincent52100

Thanks! I’ll keep my fingers crossed that I can find them.


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## vincent52100

I’ve noticed that on the Logan site that it looks like there’s two different part numbers. For example part # LP1014 (40 tooth gear) also cross references to LP1300. Is there any difference between them? Thanks!


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## vincent52100

https://www.ebay.com/itm/NOS-South-...287654?hash=item36298c31e6:g:Lb0AAOSwvktaVRzt

Good evening. This is probably a really dumb question. The above link is for double gears for a SB. Is there any chance these would work on my Logan 820. The Logan’s gears are also 16/32. Could they be adapted to work. Thanks


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## CluelessNewB

There are two different quick change gear boxes used on the 820.  The *LA-24-1* gear box was used on serial numbers 46561 and below (which is what I believe you have).  The LA-1240 was used on serial numbers after 46561. 

*LP-1130* (old LA-497) is a 40 tooth gear with an OD of 2.625" Width 0.495" and Bore of 0.438" (with bushing) used on *LA-24-1* Gear Box
LP-1014 (old LA-1213) is a 40 tooth gear with an OD of 2.1" Width 0.370" and Bore of 0.375" (with bushing)  used on LA-1240 Gear Box

LP-1300 (old LA-470) is a shaft for the gear stack on the LA-24-1 gear box

I'm not 100% sure which 32/16 gear you need but for the *LA-24-1* gear box I believe it is either one of these:  

*LP-1137* (old LA-500-A) 32/16 teeth OD 2.13/1.13 Width 0.592" Bore 0.563 
or 
*LP-1134* (old LA-502-A)  32/16 teeth OD 2.13/1.13 Width 0.530" Bore 0.563 (with bushing) 

This information came from a combination of the Logan 800 series manual, Current* Logan Catalog and the Logan Web Site

*Well as current as I have which I got from Logan about 7 years ago.


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## vincent52100

Thanks for the information. I guess I’m on the right track. Now, to track them down!


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## vincent52100

Here are the specs on the 32/16 SB gears on Ebay. Does anyone know, by the specs below, if these gears could be modified to work? Perhaps bored and thickness reduced? Thanks

Large Gear is 32T, 2.121" Dia. X. 373" thick, small gear is 16T, 1.115" Dia. X. 395" thick (both gears are 16DP) The bore (bushed) is 7/16", the overall thickness of the gear set is. 768". You are purchasing ONE DOUBLE GEAR.


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## vincent52100

I’ve gotten measurements from my old gear and the one on Ebay.
Measure                   Existing Gear.             New Gear.                     Difference
32T thickness.         .250.                            .373.                              .123
32T OD.                   2.120                           2.121.                            .001
16T thickness.         .270.                            .395.                              .125
16T OD.                   1.108.                          1.115.                            ..007
Total thickness.        .530.                            .768.                             .238
Bore.                        .562.                            .440.                             .122

The new gears are 16DP 
I’m thinking that the gears can be faced to the right thickness and bored to the proper size. Do you think that these could be made to work? 
Thanks for any info.


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## Nogoingback

Here are a couple of Tubalcain vids on repairing a Logan gearbox.  In one of them, he describes specifying gears.


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## vincent52100

Thanks for the information. I’ve looked at both videos but I guess I’m not smart enough to understand everything I need to know. I tried using the formula in the video and am getting weird numbers.
I noticed that my list of measurements posted above ran together after I posted it so I’ll try to re-do it by adding some dashes to keep everything separated.

List of gear measurements
Item——————Existing Gear—————New Gear—————Difference
Thickness———32T, .250———————32T, .373—————-.123
O.D. 32T———2.120—————————2.121———————.001
Thickness———16T, .270——————-1.115———————-.125
O.D. 16T———-1.108————————-1.115———————..007
Total Thickness.-.530————————-.768————————.238

It says the DP for the new gear is 16

I’m not sure of the existing DP. I can’t make it work out for sure.
Can the thickness and bore be machined to make the new gears work? It would br great if I could make them work. The new gears are pictured.
If anyone knows if I can make these work please let me know.
Thanks
Ken


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## wa5cab

Vincent (and anyone else)

I can't help any with your gear questions but I can explain why your first table had all of the numbers moved.  The word processor software behind the scenes is apparently programmed to delete what it considers as excess spaces.  I think that following a period, it allows two spaces but in all other cases it only allows one space.  So you did the right thing by using a printing character to substitute for the spaces.


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## vincent52100

Thanks. I’ll remember that.


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## CluelessNewB

According to the Logan Catalog I have, the LA-24-1 Gear Box used 16 DP gears. Personally I think you could make that gear work.  

(The later LA-1240 used 20 DP gears in the gearbox) 

From the Logan Actuator Parts Catalog:


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## vincent52100

Thanks very much!


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## vincent52100

Thanks! I ordered the gears. Should have them in about a week.


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## vincent52100

Now I’m starting to clean up the gears etc. under the left side cover. Someone believed in lubrication. There was so much grease packed in there that you could hardly see the gears. The picture is after I used a roll of paper towels to remove the grease. Disassembled and cleaned everything. Too much is better than too little!


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## RandyM

Vincent, you are having way too much fun.


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## vincent52100

Yes, I know! I’m really enjoying it. A couple of years ago due to health issues, we had to move from a 3 story house to a single level. Circumstances being what they were I had to sell my Logan 200. I was just starting to learn a little but I’m happy to say I’m back in the game! After the lathe is done I’m going to start looking for a mill. I’m really getting into this!


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## Chuck K

Gotta have a mill so you can make stuff for the lathe....or is it the other way around.  Either way,  both are a must.  And then.....


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## vincent52100

Absolutely true! I’ve got a long list of tools I want.


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## vincent52100

Still working on cleaning the 820. Also got the motor mounted. Replaced the 3 carriage bolts (5/16) with four 3/8 bolts.  I’m pretty sure that it is not the original and it also has a single step pulley instead of a 2 step. I will replace that when I can. I was able to find what size I needed from another post here. I’ve found a lot of information looking on this site. I’ve started cleaning the apron assembly. There was no oil in but there is no roughness or play that I can find. To me the gears look really good, just need cleaning. I’ve attached pictures of the gears. Does it look like they are ok?
Thanks a lot!


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## Chuck K

The worm gear looks good.  Does it have side to side play in it?  It's pretty rare to find one of these machines with anything more than a little bit of sludge in the bottom of the apron.  A bead of silicone on the bottom third of the apron halves when reassembling will keep the oil where it belongs.


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## vincent52100

Thanks for the info. I will do that. I can’t detect any side play in the worm. I’ve tried to look closely at all of the gears and the only problem I’ve found was the damaged gears in he QCGB.


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## gjmontll

Vincent, your mention of "side play" caught my eye. How are all the shafts and bushings?

Five years ago I overhauled/restored my 1944-vintage Logan 820.  Although completely operational, its maintenance had clearly been neglected. All the gears were fine. But the carriage and QCGB had bad wear on bushings and shafts. In particular, the front shaft in the gearbox (the one the two gear selector arms slide back and forth) was badly worn. Most of the bushings were worn enough that I replaced them all and I made new shafts.

This was my "Welcome to retirement project", it kept me busy for over a year. I don't remember how many times I had the gearbox out and completely disassembled. I took it apart to assess it, take measurements and make sketches of the shafts, then reassembled and installed it so I could use it to make new shafts. Then again tear down to install my homemade parts and new bushings, and once again reassemble.

That QCGB slider shaft was so worn, I decided to improve on the original and add bushings on the gear selector arms where factory design had been steel-on-steel (cast iron?). That was a long risky operation. If interested in details, look back to my  long series of posts, "Greg's Logan 820 Restoration".

Greg


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## vincent52100

Thanks very much. Going right now to check yours out.


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## vincent52100

Well, I got my gears in today. The only one I’m waiting for is the 40T for the qcgb. The 16x32 gears are from a SB. All they need reduced in thickness and a larger bore. Plus they are new. Pictures below.

Also, how do I disassemble the spring loaded pin on the change levers? I looked at Greg’s 820 restoration. lots of info I need but I couldn’t find how to disassemble the lever. One pen is bent. I can possess straighten it. I have a picture of that also below.
Thanks!


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## Chuck K

There is a pin that you need to remove from the handle to pull the shaft out of it.  Wire brush the handle real well and you will see the pin.  I don't recall if they used a taper pin.  You should be able to tell by comparing dia. from side to side.


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## vincent52100

Thanks!


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## vincent52100

Got the pin out. still won’t come apart. Got it soaking in PB Blaster. I’ll try it again tomorrow. The fellow I got it from said that it had sat in the back of a auto repair shop for several years. The more I work on it the more I’m sure that it sat for a longtime. The grease is so hard that I have to use a pick to get it out. Definitely not rusted.


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## Chuck K

vincent52100 said:


> Got the pin out. still won’t come apart. Got it soaking in PB Blaster. I’ll try it again tomorrow. The fellow I got it from said that it had sat in the back of a auto repair shop for several years. The more I work on it the more I’m sure that it sat for a longtime. The grease is so hard that I have to use a pick to get it out. Definitely not rusted.


Seems like I have had to clamp the handle in a vise and knock the shaft out using a small punch.  They get corroded.


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## vincent52100

Tried the small punch, no luck. Tried heating it but I only had a propane torch so that didn’t work. I figured, what the heck, I’ll try straightening it. I was able to fit a crescent wrench and little by little I was able to straighten it. It’s not perfect but pretty darn close. I’ll try it manually when I get the gear case back together.


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## vincent52100

Still working on my 820, trying to correct any problems as I go. It all is pretty minor except for the gear box. Most difficult part is cleaning up the gears and shafts. It’s so dry that it’s coming off in strings, like the protective coating on some new parts. I’ve got the new gears, except for one where I thought I was ordering a 40t gear but it was a 46. I should have cleaned my glasses. (I have a new or almost new 46t change gear for an SB9 if anyone would want to trade for a 40t 16dp).I have run into a problem. I don’t have the tools to face off the gears to the right width or or accurately bore the holes for the bushings. Can anyone recommend a machine shop in the Asheville NC area? I’m pretty sure a production type shop is out of the question. I posted some pictures below. Thanks for all the help and advice I’ve been getting. 
Ken


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## vincent52100

Wow! Another problem. Looks like I'm missing something. Gotta start looking.


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## Chuck K

It probably had a collet closer on it at one time.  When that was removed they took the special nut with it.  The nut you need shouldn't be hard to find.  I think logan still sells them.


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## vincent52100

I checked EBAY and there are none out there. I checked Logan and they do show it. Looks like I will give Scott a call.


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## wa5cab

Chuck is probably correct.  The most common way to add a lever operated collet closer to most of the 6" to 12 or 14" US made lathes is to remove the bearing preload or end float adjusting nut and screw the closer onto the spindle, where it serves a dual function.  It is unfortunately the exception rather than the rule for the owner to keep and know where to find the nut that he removed.  Later when the lathe is being sold, someone offered a good deal for the owner or his heirs and bought just the closer.  And of course the nut was nowhere to be found (if the seller even knew that it was supposed to be there).


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## vincent52100

Making slow but steady progress on my lathe. Got the apron cleaned and put back together. Replaced the bushings. The worst ones were the ones for longitudinal handle. It had two bushings that were 3/4” long, seems to be not enough support. I used a long bushing and made an opening to line up with the oil hole. I put grooves in to carry oil the length of the shaft. It feels very smooth. There are a couple of other problems. The cross feed screw has a small bend that seems to make the travel harder at one end. Hope to figure out how to straighten it. But one other problem, I have a piece and don’t know where it goes. I took pictures but can’t find that part. I really hope I don’t have to take the apron apart again. Hope someone can tell me what it is!


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## Nogoingback

Not sure what those parts are: they don't look like anything on mine.  Have you purchased or downloaded the parts diagrams
for your lathe yet?  It's worth having them, and you can get them from Logan.


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## Chuck K

Parts from the clutch?  Doesn't make sense because you seem to have it reassembled.  Been a while since I've had an apron apart and my memory is terrible.


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## CluelessNewB

Maybe those parts are LA-313 & 026 from the banjo?


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## vincent52100

That’s it! Looked at the parts diagram for the apron and never thought to look at the other parts. DUH!


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## wa5cab

I agree with Rich that the two parts in your 3rd and 4th photos are LA-313 and 026.  You should also have loose the rest of the parts along the line from LA-312 to 026, not including the banjo or change gear bracket.  As you set up for different feeds or TPI's, you will have a variable number of that group of parts used.  But I don't know enough about Logan's to guess where the bushing or sleeve with the hole in the side belongs (assuming that it is also still loose).


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## Nogoingback

NOW I remember.  Sorry, should have last night but it was late and after a long day at work.  Here's what that assembly looks like:
not shown in the parts diagram are the change gears bolted to LA-314, which is a bronze bush.  The gear/bushing assembly rotates
around LA-313, which is bolted to the banjo.  If I remember right, LA-232 is a washer that provides some space between the two
gears.  If the gears have to be changed, the large nut in the center of the gear is removed.  Notice that there is a keyway in LA-314
and it's associated key, LA-249.  When I went through my lathe, some of those parts were missing, but Logan was able to supply
replacements.


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## wa5cab

Yes, the keys and keyways connect the two gears or gear and spacer at each location.  If necessary for the ratios, this makes the two gears into a compound gear, which, except for using a different size gear at the screw gear location, is the only way to change the ratio between the spindle and the lead screw to achieve the desired feed or TPI.  Note that unless two gears are being operated as a compound gear (input to one and output from the other), the ratio between the spindle gear and screw gear is the same regardless of what gears are in between.  The only requirement on any of the other gears is that they physically fit.  This is a fact that for most people is difficult to accept.


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## vincent52100

Thanks! I checked and I do have all the parts.


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## vincent52100

Got my gears back from Tom at Hill Top Machine Works (NCJeep). Check his videos on YouTube. Can’t tell you how much I appreciate it. Tom saved me more than $900 off what the new Logan gears cost. I’ve attached some pictures. I’m going to do a write up on what gears were used etc in case another Logan owner faces similar problem. Again, Tom I really appreciate it!


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## jdedmon91

vincent52100 said:


> Got my gears back from Tom at Hill Top Machine Works (NCJeep). Check his videos on YouTube. Can’t tell you how much I appreciate it. Tom saved me more than $900 off what the new Logan gears cost. I’ve attached some pictures. I’m going to do a write up on what gears were used etc in case another Logan owner faces similar problem. Again, Tom I really appreciate it!



Here is NCjeepers video of the gear mod 







Sent from my iPhone using Tapatalk


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## NCjeeper

Just found this thread. Your welcome Ken and I hope the modified gears work out for you.


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## vincent52100

They worked great! Got it back together and will post some pics. Gotta get the motor problem fixed and I’ll be good to go.


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## NCjeeper

Good to hear that. Some pics would be nice.


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## vincent52100

I did a dumb thing, I got so involved in making  sure that I got it right that I completely forgot to take pictures until I was done! I’ll put some pictures on after I get it cleaned up.


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## NCjeeper

10-4.


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## vincent52100

Its done! Everything works as it should. I ended up replacing 4 gears, several bushings, backup nut on the spindle and the wiring. I appreciate all the help I've received here. Guanteed that I would still have a pile of parts except for this forum. I'm going to do a seperate write up on the gears and how it all worked out. All told I've put 208 dollars in a 700 dollar lathe. I think I got a great deal! Now to find a mill, bandsaw, tooling, etc. etc.
Thanks again to everyone who helped me.
Ken


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## NCjeeper

Well I saw a nice Atlas 7 shaper for sale on E-bay in your backyard. Might be worth checking out if you want more equipment.


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