# gear train rebuild



## Flyrod (Jun 10, 2017)

Hi Guys

Several questions if I may

I am just starting to clean up a new to me 11" logan lathe (model 957 - cabinet model with motor underneath)

I am hoping to take off all of the change gears, clean, replace bearings/bushings and reassemble

Same for headstock

This thread is just the reverse gear/change gear assembly




as you can see in this picture, one of the idler gears is off...it had a broken tooth and so I started with it - it comes off very easily with a nut behind and then pulls out - the gear has an oilite bushing and it slides snugly over a pinion stud

(I know i said headstock for later, but I am using the spindle gear as the first gear on the drive train)

for the spindle gear, is the threading on that part of the spindle left or right? - assuming right, but before I start cranking on it, figured i'd ask

the collar that is outboard of the spindle gear...that just needs a spanner wrench to unscrew? - i did not see any other set screw, key, etc - is that correct?

jumping back down to below the idler gears is a coupled set of two gears, the bottom one is called the reverse gear and the one that sits on top of it is called the stud gear

as per the picture and the parts diagram, there is a retaining nut on this assembly - i have removed this - if i had to guess, it looks like the stud gear is pressed on to the spacer (part 261), which spacer is pressed on to the reverse gear shaft (part 138), which has a woodruff key in it - is that right?

if so, there might be enough room to get a small puller behind the stud gear and pull it off

but the reverse gear is flush to the feedlever - there is no way to get anything behind it to pull it off

it looks like the lever itself is pressed on to the reverse gear shaft - so is the idea to take the lever out and the stud and reverse gears come with it?

also, where does the reverse gear shaft terminate? - when i look in the headstock i cannot see its terminus (although there is a cast piece above where all of that is so maybe it is hidden under that?)

moving on to the change gear assembly:

unfortunately, the change gear assembly parts diagram is not nearly as helpful as the reverse gear assembly

the standalone gear you see pictures of is part LA-213 and 214 - it is a coupled gear set of 2 gears one 48T and the other is a ?? T

 it is not clear to me how to dissasemble this

the hex head cap screw pushes through the middle of that assembly and then bolts through the square nut that sits on the other side of the banjo bracket - once that is off, there is the nut below it that is still on in the pictures - it is threaded on but there is no way to gain purchase on the gear stud to apply torque to the nut (that i can figure out)?? so how would you disassemble it?

on the final change gear, it is also retained by a nut - but the shaft it is on does have a center machined out and so i assume one is to pull this off with a puller

it is not clear how that shaft attaches to the banjo (or change gear) bracket

it is also not clear if once i get that last gear off, can i simply slide the banjo bracket off (after loosening the retaining nut and bolt)?


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## Chuck K (Jun 10, 2017)

Remove the gear in front of the banjo, lossen the pinch bolt and the banjo bracket will slide off.  The banjo bracket should have a bracket that attaches it to the headstock on the other end. Perhaps you have already removed it.


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## wa5cab (Jun 11, 2017)

To remove the spindle gear (top of your first photo), first remove the threaded collar, which I would assume has right hand threads.  However, that collar should have one if not two set screws in it.  With a lead or brass pellet in the bottoms of the tapped holes.  Otherwise, the only thing holding the collar on the spindle would be torque and friction.  After removing the collar, the gear should slide off although it might be "glued" to the spindle by varnish left when oil evaporates.

The 48T Stud Gear at least should slide right off unless it is also glued to the stud.  Same for the spacer and the gear erroneously called Reverse Gear.  But I have no idea what holds the tumbler (FWD-OFF-REV Lever or Bracket (LA-1026) to the headstock casting.  That may be shown on the headstock assembly drawing.

Ref. LA-1025 Reverse Gear Assembly drawing,  Banjo = Change Gear Bracket #14.  To remove it, first remove the already loosened nut on the end of the gearbox input shaft (not shown on drawing).  Then remove collar 16 and gear 15.  Loosen pinch bolt 17 and 14 should come off.  The missing bracket that Chuck mentioned is #8.


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## Nogoingback (Jun 11, 2017)

Flyrod, I've never worked on an 11" machine, but I just went through this with my 10" lathe so imagine assembly would be similar.  The collar on the end of the spindle is the "nut" that holds
the gear in place.  Mine had right hand threads and required a pin spanner to get it off.  The gear was keyed. I had no problem getting those parts off with the correct wrench.

On mine, the entire reverse gear assembly is secured at the bottom with a metal plate and two screws that hold it in place.  In your picture I can only see one, but if it's the same, just remove
the two screws, and the assembly will come out: it simply pivots around a hole in the headstock.  (The hole lines up with the shaft for the backgears, but they are separate parts and are
not connected.). Then you should be able to disassemble it without difficulty.  None of my parts required a puller.

On the change gears, you are correct, the nut comes off and they come apart.  Honestly, I've forgotten how I did it but I had no problems with them.  Try holding the larger gear in a vice
with some soft jaws and gently remove the nut.  Sorry  I can't give you a better answer, but I think that's how I did it.

For the bottom gear, mine just slid off when I removed the nut: no puller was required.   It should be secured with a woodruff key.  Chuck K is correct, loosen the pinch bolt and the banjo should slide off.

As I said, my machine is a 10", but I doubt it differs much: all your parts look just like mine.  Nothing I did required a puller or  force to disassemble.  The only special tool
was the pin spanner which I had to search the internet for.  I'd give you the part number, but yours will be different since your spindle is larger than
mine.

One problem I encountered was that some parts were missing or replaced with substitutes that weren't really correct.  Once you get it apart, it would be helpful to study
the parts manual carefully to ensure that everything goes back together correctly.   If you have missing parts, Logan can supply them: I had to buy a few things.  (Or of course,
there's eBay.).


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## Nogoingback (Jun 11, 2017)

wa5cab said:


> To remove the spindle gear (top of your first photo), first remove the threaded collar, which I would assume has right hand threads.  However, that collar should have one if not two set screws in it.  With a lead or brass pellet in the bottoms of the tapped holes.  Otherwise, the only thing holding the collar on the spindle would be torque and friction.  After removing the collar, the gear should slide off although it might be "glued" to the spindle by varnish left when oil evaporates.
> 
> The 48T Stud Gear at least should slide right off unless it is also glued to the stud.  Same for the spacer and the gear erroneously called Reverse Gear.  But I have no idea what holds the tumbler (FWD-OFF-REV Lever or Bracket (LA-1026) to the headstock casting.  That may be shown on the headstock assembly drawing.
> 
> Ref. LA-1025 Reverse Gear Assembly drawing,  Banjo = Change Gear Bracket #14.  To remove it, first remove the already loosened nut on the end of the gearbox input shaft (not shown on drawing).  Then remove collar 16 and gear 15.  Loosen pinch bolt 17 and 14 should come off.  The missing bracket that Chuck mentioned is #8.



Robert, you beat me to it. , I think we were typing at the same time.

On my model 200, the threaded collar for the spindle has no set screws: it was simply tightened like a nut.   My 618 has a set screw like that.  The
difference is due to the fact that as you know. on the Atlas the nut is used to adjust the spindle bearings, but on the Logan it isn't.


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## wa5cab (Jun 11, 2017)

Yeah, I remembered that a few minutes after I hit the POST button.


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## Flyrod (Jun 11, 2017)

Nogoingback said:


> On mine, the entire reverse gear assembly is secured at the bottom with a metal plate and two screws that hold it in place. In your picture I can only see one, but if it's the same, just remove
> the two screws, and the assembly will come out: it simply pivots around a hole in the headstock. (The hole lines up with the countershaft, but they are separate parts and are
> not connected to the reverse gear assembly.). Then you should be able to disassemble it without difficulty. None of my parts required a puller.



Nogoingback - thank you! - worked the same way on mine - once off, i was able to get the gears off the lever assembly


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## Flyrod (Jun 11, 2017)

wa5cab said:


> Ref. LA-1025 Reverse Gear Assembly drawing, Banjo = Change Gear Bracket #14. To remove it, first remove the already loosened nut on the end of the gearbox input shaft (not shown on drawing). Then remove collar 16 and gear 15. Loosen pinch bolt 17 and 14 should come off. The missing bracket that Chuck mentioned is #8.



Robert - thank you! - worked like a charm - the gear was a little frozen on but i used the banjo to "slide hammer" into it a few times and it came loose

To all - thank you!

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Next, up the headstock and quick change gear box...more coming!


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## Flyrod (Jun 11, 2017)

well...errr...having looked more closely at this video:






and the parts diagram attached, maybe i won't rebuild the quick change gear box but just detach it and clean it!?


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## Chuck K (Jun 11, 2017)

If everything turns free and there isn't a lot of wear in the bushings there really isn't any reason to take the qc box apart.  On the other hand, if you decide to take it apart, it isn't as hard as you might think.  The most challenging part is getting the keyed gears back on the shaft on the output side. There's a simple trick to make that go a lot easier.


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## wa5cab (Jun 12, 2017)

I agree.  If'n it ain't broke, do'n fis it.


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## MBfrontier (Jun 12, 2017)

Chuck K said:


> There's a simple trick to make that go a lot easier.



CK, I'm interested. Thanks.


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## Flyrod (Jun 12, 2017)

Yes pls - what is the simple trick?

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## Chuck K (Jun 12, 2017)

If you have an old shaft with the keyway cut in it, slide those gears with the key on the shaft while pushing the shaft through the right end.  It will be easy to do because you won't have the gear cluster on the other end in your way. Once you have them all in place with the shaft no more than flush with the outside of the last gear,  put the gear clusters on the other end and push your good shaft through from the left until it meets the other shaft.  At that point line the keyway up and push the old shaft out the right end.  It can be done with a piece of dowel if you don't have a worn shaft laying around. I hope that makes sense.


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## Flyrod (Jun 14, 2017)

Thx

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## MBfrontier (Jun 15, 2017)

Thank you, CK.


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