Spindle Indexer

dlane

dlane

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Anyone have a pic of the bull gear index pin assembly, mine is missing would like to use it.
This is a old lathe may have to go thru it , the bull gear has a bunch of index holes around it , do they all have this index capability, never noticed before ?.

image.jpeg
The pin goes in the headstock casting close to where the bull gear guard bolts down in front .
It is a 12x36 possibly the first craftsman/atlas ever made
Thanks
 
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I ended up making the index pin on the Heavy10 it works really good , no slop.

image.jpeg To lazy to count the index holes , how meny you think are in the bull gear ?. May have to make larger dials for it now.

image.jpeg
Drilled a small hole in casting to hold down spring / plunger to get it in there. Adapted a tailstock turret to this machine last week , to drill 50BMG bullets out for wrighting pens. Hope she has it in her :apathy:
Thanks
 
Derrick,

Your machine appears to be a 101.07380 and looks to be very nicely restored. All of the Atlas built lathes with back gears have the indexing holes in the bull gear. The models that could be bought without back gears had the holes in the spindle cone pulley. Don't ever use it to lock the spindle for something like removing a chuck.

The part # is 10-42A. The vertical hole visible above the horizontal hole for the pin is for a spring and ball that sit below the pin and provide enough friction to keep the pin from moving while the lathe is running. Mine has worked fine for 35+ years. I thought that we had a factory drawing of it but couldn't locate it and when I tracked down the thread where I recalled discussing it last year, discovered that the thread finished with the owner intending to repair his pin. So I took the dimensions off of the one in my 3996 and made a drawing. You will find it in Downloads. Click on where it says "Click here", click on Machine Manuals..., Atlas/Craftsman/AA, and Atlas Drawings.

The ball is 3/16" diameter steel. The spring is also 3/16" dia. but I don't know the length. It would be about 1/16" to 1/8" longer that the depth of the hole below the pin hole. Note that the 3996 parts manual called out a 5/32" dia. roll pin but mine actually has a 1/8" dia. solid pin in it. The pin is probably a groove pin.

FWIW, I think that in 35 years, I've only used the index pin once or twice but if you ever wanted to make a graduated dial, engrave marks and stamp numbers on it, the index pin would be handy for that.
 
Thanks Robert, this is an interesting machine. I wish my 10L had a indexable spindle built into it.
The pin,spring and brass piece seem to work good ,once I got them in there.
Last week I fit a tailstock turret to the lathe , I got the turret for my 10L but it is to tall for it .
Going to use craftsman lathe to drill a series of holes in 50 BMG bullets ,for wrighting pens.
The er40 Chuck is a little slow though ,
image.jpeg
Is there a quick acting collet closer that would work on this machine
Had to make the adapter plate, its dialed in perfect.
Hope the lathe is up to the task.
Thanks
 
Also there is no reference marks on bull gear holes, think I'll count them and make marks of some sort
Any ideas on how to mark them , # for each hole ?
 
wa5cab said:
The part # is 10-42A. The vertical hole visible above the horizontal hole for the pin is for a spring and ball that sit below the pin and provide enough friction to keep the pin from moving while the lathe is running. Mine has worked fine for 35+ years. I thought that we had a factory drawing of it but couldn't locate it and when I tracked down the thread where I recalled discussing it last year, discovered that the thread finished with the owner intending to repair his pin. So I took the dimensions off of the one in my 3996 and made a drawing. You will find it in Downloads. Click on where it says "Click here", click on Machine Manuals..., Atlas/Craftsman/AA, and Atlas Drawings.

The ball is 3/16" diameter steel. The spring is also 3/16" dia. but I don't know the length. It would be about 1/16" to 1/8" longer that the depth of the hole below the pin hole. Note that the 3996 parts manual called out a 5/32" dia. roll pin but mine actually has a 1/8" dia. solid pin in it. The pin is probably a groove pin.
Click to expand...

New guy here. Can someone provide a link to the drawing discussed above? I am not able to find it. On my 101.27440 lathe I have the pin, but the small male protrusion to engage with the bull gear is gone and I do not have a spring loaded detent in the head stock hole.

Thank you

-larry
 
Thank you. What is the radial 0.125" hole near the tip for? Is that where a spring loaded detent (ball) rides in the hole in the headstock?
 
No. That is for the 1/8" dia. pin that gets installed after you slide the index pin through the hole in the headstock over the spring loaded ball. It just keeps you from accidentally pulling the index pin out of the headstock (and probably losing the ball and spring). There is no groove or ring for the ball. It just holds the index pin in position by friction.
 
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