Large dial upgrade on 11" R model slide.

after reading all the posts about upgrading the dials on the 9 an 10s I decided I would do mine as it needed a new screw and nut anyway.
My 11 is different, see pictures,
The new Acme is installed and drying and it will be pinned in front of the gear in the 1.125 smooth stub in front.
There is no large shaft behind the gear , what you see is what it is.
The shaft measures .625 o.d. with a lighter cut in between at .600 and everything behind the gear is 5" long O.A.
The small dial bushing as shown in the picture has one thin brass washer that buts up behind the gear,, the bushing goes a ways into the slide before threading.
Even though threads are at the front of the slide.
My intension is to use most of the .625 o.d. shaft, turn the bushing down at where the hex nut is to a manageable size and make a 1.750 size short bushing to "sweat" on to this original bushing, then turn down the exposed .625 shaft to the .375 size and continue on from there with the 200 type dial and short bushing/bearing.
Anything wrong with that?
I need opinions , I only have the one gear shaft.
Thanks
Ron

picture

Before I start I need to ask some questions pertaining to the bushing and the shaft reduction to 3/8".
Do you reduce the shaft size because of the bearing that you have to use behind the pinion? So that you can get it into the threaded bushing hole O.D. ?
and that the bearing comes in that i.d. (3/8") size?
If so my question is this, I dont know what the pinion or bushing o.d. measures on the 9 and 10s which are the ones discussed.
On my 11" the pinion measures .940 on the o.d. and the bushing pressing to it is @ 1.000
The threads measure 1.050.
shaft measures .625.
Are these 9 and 10 sizes?
If not then could I use a larger bearing than the ones called for on the 9s & 10s?
If there is one that is larger o.d. then its possibly has a larger i.d.?
Like 7/16" or even 1/2", this would help in the outer bearing/shaft/sleeve would it not?
Thanks Ron

Hi Ron,
Thanks for the e-mail, I think you have a good plan. yes 10 TPI is the same as the 9 or 10 dials. and yes, there are larger Boston Gear bearing sets. MSC part# 03548609 is a Boston Gear 17196 thrust bearing set that is .500 ID x .875 OD x .375 W. you will need two sets. one for the lower shaft at the gear and one for the upper in the bushing/dial. I would just turn down your shaft to just under .500 and fit these bearing sets. On the front bushing, Yes a two part bushing is fine, and you can just use 680 loctite in a close slip fit. you can turn a step down on the front of the shaft to accept the thrust bushing for the dial. Don't forget to check the position of the dials and handles between compound and crossfeed, with larger dials you may have to make a longer bushing and graft a shaft extension on the small dial shaft to gain the extra length for the dials and handle to swing freely. you can use bronze inserts in the CF bushing ends for the shaft fit. Here's a good thread from this year that will give you some good ideas. Send me pictures in email as you go through it so I can follow.

Steve Wells

swells said:

Here's a good thread from this year that will give you some good ideas.

Click to expand...

http://www.practicalmachinist.com/v...-9-heavy-10-cross-feed-repair-replace-239577/

Thanks Mr. Wells
I think I have it tought out how to do it .
My goal is to use as much of the original shaft o.d. as I can and use the original threaded bushing by taking off the part that is behind the pinion to the width of the bearing and turning the nut part down to a slip fit just to where it contacts the slide housing to accomodate a longer bushing @ 1.750 o.d. for the dial. make silver solder this onto the old busing or locktite and pin ?
Then to terminate the old shaft inside this bushing just enought to allow the larger bearing to be used in its recess where the shaft will be 3/8" o.d will be added to it here with a slip fit for a pin and some 680.
That is IF my original shaft is long enough ?
I will go thru Bostons Bearings see the bearings.
One thing though I am in the process of restoring this 11" lathe and I need to do these mods but I only have access to a 6" Atlas to make the shafts and busings, it may be more than its accruate enough to do.
I surely cant use the 11" while I have the slide apart.
It may be a few weeks before I get all the pieces but will take pictures of what I do so the rest of you wont make my mistakes!
Thanks for the help,
Ron

I should ask , "how long is the bushing from the edge of the cast iron slide to the front face of the bushing?
That will determine how long of an extension I need to make to slip fit over my bushing.
Ron

That depends on how much cross slide travel you want. You'll want to at least preserve what you had before. I have a bushing from either a 9 or 10k here, and it measures 2.38" from the bushing face to where it meets the saddle casting. When fully retracted, you want enough gib engaged for stability. Ultimately, the limit is imposed by the crossfeed nut butting up against the saddle casting.

I guess I will not be able to retain the original size of the shaft as I cannot find a bearing that is .625 x 1.00"
So that means I cannot use the original threaded bushing as a stub to build and extension on. I cant find a maker that makes one.
Paul , I dont see why the threaded bushing would have anything to do with amount of slide travel, unless i am missing something ?
The amout of travel I belive only pertains to the threaded side of the shaft?
I was just needing a measurement from the face of the slide to the face of the bushing that rides against the dial.
So it would not interfer with the compound.
Thanks
Ron

Finally found some thrust bearings that will fit the .625 shaft and are 1" o.d. the down side is that they are .500 thick but really quality ball bearings with grooved races.
INA bearing #2006
So not I can retain my 5/8" shaft all the way to the large dial and only reduced then to go thru the bushing on the graduated dial.
One down side is a deeper cut on the large dial bushing for the .500 thick bearing.
I pinned the acme thread to the locktited gear shaft with a .100 taper pin.
Ron