# Motor and Countershaft Assembly questions on Atlas 618



## Darla (Mar 17, 2014)

I have an Atlas 618, probably model 101.21400 [unsure because ID plate is missing]. I'm just starting to clean/review this machine.
 The motor I got with it is not the motor listed in the manual. They are 1/2, 1/3, and 3/4 hp; mine is 1 hp.  Other info from my motor:  
Dayton AC Induction Motor
1725 rpm
Model 6k223c
Hz: 60
Duty: cont
It seems to have various configurations with 115 or 220 v.  I am not well versed in electrical matters so this is a bit of a mystery. 

The Atlas 618 manual shows a Countershaft Assembly with motor mounted directly behind the headstock, with a bracket, hanger, and various pulleys.  My setup is different.  My countershaft bracket is not the same, and the motor is a good 13" behind the countershaft.  This all seems to work but I'm not sure it's a good setup.  Also, it requires more space.  I will have to get a new table to accomodate this L shaped arrangement.

Does anyone have experience with mounting the motor so far behind the lathe?  Any suggestions?  
Thanks,
Darla


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## Dave Smith (Mar 17, 2014)

Darla said:


> I have an Atlas 618, probably model 101.21400 [unsure because ID plate is missing]. I'm just starting to clean/review this machine.
> The motor I got with it is not the motor listed in the manual. They are 1/2, 1/3, and 3/4 hp; mine is 1 hp. Other info from my motor:
> Dayton AC Induction Motor
> 1725 rpm
> ...




Darla--it looks like you could find a much shorter belt from your jack shaft to the lathe and move the jack shaft closer to the lathe-- then make a bracket to mount your drive motor under the jack shaft with a shorter belt also---that would take up much less space--Dave


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## wa5cab (Mar 17, 2014)

Darla,

As Dave said, both of the belts are much longer than original.  And a 1 HP motor is larger than needed even on a 12x36.  On the 6" it's 'way too large.  If something ever jams, something is going to break and it won't be the motor.  I would recommend that you get one no larger than 1/2 HP and preferably 1/3 HP.  

Some photos or drawings in the manuals show the motor behind the headstock and countershaft and some show it to the left of the countershaft.

There were two different countershaft brackets supplied with the Atlas and Craftsman 6" machines.  You have the early one, L9-20A, with the countershaft mounted above the rockershaft.  The later one shown in all but one of the 6" manuals that we have is M6-20B.  It's much taller, and the countershaft hangs down from the top of the bracket instead of sticking up from it.  The only mounting hole template that we've been able to find is for the later one.  It shows the two bracket mounting holes nearest the bed as 3-1/4" to the rear of the rear edge of the rear way.  The two holes are shown as equidistant to the left and right of the nearest bed leg mounting bolt.  However, I would recommend getting the correct belts and checking before drilling any holes.

According to two or three owners, the original spindle belt is 3L350 and motor belt is 3L210.  That's with the proper size motor.  And with the later countershaft bracket.  The motor belt part numbers are the same (L9-125) early and late.  However the spindle belt (AKA cone belt) part numbers are different, L9-125A early and M6-127A late.

Also, both the motor pulley and the large countershaft pulley should be 2-step.

Robert D.


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## Dave Smith (Mar 18, 2014)

Darla---how are you coming on your lathe--once you find a shorter belt to mount the counter shaft closer to the lathe--or just using the same belt so you do not need to take your spindle out to replace the belt--they also make link belts that can be taken apart and put back together for convenience(they are real handy and run smoothly)---then the rest is just making a motor mount under your counter shaft and finding a belt the approx length--you can mount the motor base on a hinged base so the weight of the motor keeps the belt tension----nothing is technical as far as the mounting of the motor--or the size---a 1/3 or 1/2hp would be better with a small pulley and it should be just a 110volt motor that has a 1725 rpm--let us know if you still have questions----Dave


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## wa5cab (Mar 19, 2014)

The motor on the various Atlas 6" models all bolt directly to the bench or stand.  Process (with original belt lengths) was that after bolting the lathe down, you mounted the countershaft bracket at a distance behind the bed such that when you operated the lever driving the rocker shaft, it tightened the spindle (cone) belt adequately.  Then you positioned the motor behind the bracket or to the left of it, put the motor belt on both pulleys, and pushed it to the rear until the belt was tight enough, keeping the motor shaft parallel to the countershaft.  Then (with your third hand) you marked the hole locations for the motor mounting screws.  Once the motor is mounted, the rocker shaft lever tightens and loosens both belts at the same time.

Robert D.


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## FarFar (Mar 19, 2014)

My Boxford was put on stone and got a VFD.
Was much better afterwards.
Am space restricted in my new home and is working on puttin motor directly over headstock,but basicly the same.


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## FarFar (Mar 20, 2014)

A picture of the very scientific CAD assisted clearance testing of powertwist belt relative to backgear shaft and headstock casting.
It is very close.


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## JRT (Oct 7, 2022)

wa5cab said:


> Darla,
> 
> As Dave said, both of the belts are much longer than original.  And a 1 HP motor is larger than needed even on a 12x36.  On the 6" it's 'way too large.  If something ever jams, something is going to break and it won't be the motor.  I would recommend that you get one no larger than 1/2 HP and preferably 1/3 HP.
> 
> ...


Hi Robert, I know this is of course a long shot seeing how this is an older post but thought I'd ask anyways in hopes of you know as it seems that you know a lot about these lathes... Do you know why I'd have rubbing on the upper rear side of the spindle lid/door and the jack shaft where the belt passes beneath the cast cross member just in front of the 4 step pulley? I got some 3L link belts that don't seem to sit down deep enough in the pulleys and I tried a 1/4" belt but it seems a little too small. Any advice from anyone would be greatly appreciated. Thanks. -John


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## wa5cab (Oct 9, 2022)

John.

According to many different owners, the spindle belt for all of the various countershaft bracket's, etc, is a 3L350.  So the only reasons for the belt rubbing either headstock or closed belt cover would be wrong spindle height, belt length or wrong bracket height. Or wrong distance from the lathe of the countershaft bracket.  There are several different copies of the 6" mounting hole templets in Downloads.  However, access to Downloads does require doner status.


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## JRT (Oct 10, 2022)

Thanks. I did put the link belt back on and tensioned it and also moved the counter shaft a little and it seems like it will be fine now!


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