Webster Whitcomb headstock setup questions

[rjenkinsgb]

2 hours ago, caseback said:

I use a synthetic 5w-30 motor oil in a syringe to lubricate my lathe.

Mobil 1 is excellent for anything from PC fans & small motors upwards!

[mbwatch]

Other projects and visiting family meant putting the lathe build aside for a couple weeks, but now I have more parts and progress.

I couldn't find a dog point set screw with a slotted head rather than hex, and I didn't want to mess with easy to strip hex screws anymore. So I spun a 12mm long M4 slotted set screw in a drill (since I don't have  a lathe yet) and ground it with a stone drum in a Dremel into approximately a dog point to fit the spindle hole. I redrilled and tapped the pulley for the M4 screw.

Aligning the spindle to the hole in the pulley was harder than I planned on since they are very tightly fit and unable to rotate or slide once in place. Took me 5 or 6 tries tapping the pulley on and off again until I nailed the screw hole placement and could get my screw all the way in.

I assembled the rest of it, but I am still finding that the rear bearing binds up at a high spot, unless I press the bearing on not quite all the way, with maybe 0.05mm of play. I have ordered some Timesavers Lapping Compound as suggested by nickelsilver and will hopefully smooth that out to stop it binding. Once it grabs hold, it locks up completely.

Should there be any play end to end on the spindle in the bearings? I assume not, and that the oil lubrication should form a barrier only a couple microns thick when the bearing is pressed on as far as it can go. I watched Jon's video assembling a Wolf Jahn headstock and he closed in the bearing's locknut then backed it off a tiny bit, but with no axial play. Right now I just can't assemble it without a tiny bit of axial play, but hopefully lapping the rear bearing will correct that issue.

Lastly, I might file a little cutout into my brass end cap dust covers as most other lathes seem to have. It is inconvenient to have to slide them back in order to access the oil holes because they're a really tight fit.

And since I don't have a big vintage motor (just a little modern sewing machine motor), mounting at the back of the Borel base was a hassle and frankly ugly. I found in a random clockmaker tools lot on ebay a lathe foot/pedestal that looks to be the right type for my bed. If it arrives next week and does fit, I will sell off the Borel base and instead mount everything on a heavy wood board as everybody except JD Richard seems to prefer.

Even if I never get around to turning any stock on this thing, it has been a lot of fun learning how it works. And like everything else in watchmaking, very impressive that it could be manufactured to such precision 70 or 80 years ago.

 

[Neverenoughwatches]

54 minutes ago, mbwatch said:

assembled the rest of it, but I am still finding that the rear bearing binds up at a high spot, unless I press the bearing on not quite all the way, with maybe 0.05mm of play. I have ordered some Timesavers Lapping Compound as suggested by nickelsilver and will hopefully smooth that out to stop it binding. Once it grabs hold, it locks up completely.

Were the bearings lubricated at this point?  My lathe arrived dry as a bone and howled until I oiled it.

[mbwatch]

9 hours ago, Neverenoughwatches said:

Were the bearings lubricated at this point? 

Yes. One bearing if pressed tight will grab and hold firmly until tapped with a brass hammer, regardless of lubrication. I expect lapping it will help.

Edited February 16 by mbwatch

[Dell]

Don’t cut a slot in the brass shroud because they are designed to keep swarf out , you say locks up unless tapped with a brass hammer, tapped from back or front , if the spindle runs free after hammer tap then the spindle & or bearing is not seating properly try removing part in picture and rotate 180 degrees 

[mbwatch]

10 minutes ago, Dell said:

try removing part in picture and rotate 180

Hi Dell - I am not sure how I could rotate that part, since it is keyed to the spindle. But a few weeks back we determined my rear headstock bearing was not affixed to the frame, and I have since installed it with loctite sleeve retainer.

When the outer part of the bearing was out of the frame and also since it was installed to the frame, the inner piece you labeled will tend to bind on a high spot.  So I can rule out an issue with the bearing being crooked in the frame. To free it, I can tap the seam where the two bearing pieces meet as suggested by caseback. It will bind regardless of whether it's installed on the spindle if I push the two bearing surfaces together too firmly and rotate to the high spot. (I could also tap it from the rear of the spindle)

Right now I have the end locknut in position where it all moves very freely without binding and without any axial play that I can feel. If I were to tighten the locknut just a little more it will cause the spindle to bind up. So it does feel like it's seated but something on the bearing surfaces can hinder motion.

[Dell]

So the spindle turns in the part I linked to the ones I have done that part rotated with spindle if memory serves, when setting up axial play the not should be tightened then loosened until no play and free to turn.

[mbwatch]

Project Update:

Timesaver Lapping Compound is really amazing stuff. I was able to eliminate all the binding high spots on my spindle bearings.

I started with the rear bearing which was the one that would lock up completely. It took 4 or 5 rounds of twisting that bearing with my fingers using the Timesaver compound to get it to where it would turn 360 smoothly, but it could still lock up when contacting the frame bearing 100% So for that I had to assemble it tightened down and lap it, which worked. No more binding of the rear bearing.

When fully assembled and the locknut all the way in, I still had a high spot where the pulley would slow. I could not figure out where it was, so I did two rounds of disassembly and assembly of both front & rear bearing with Timesaver compound, gradually tightening the locknut until it was all the way in and I could spin the pulley all the way around without slowing. At that point I took it apart and cleaned it all up again, reassembled with oil and now it runs fully smooth with the locknut as far down as I can turn it.

The Timesaver compound leaves a light gray, very uniform matte finish. This part started out with a polish but the fine matte turns so much more smoothly. You can see the finish on both the inner angle and the outer steep angle. It obviously does this to both mated parts of the bearing.

 

I am beyond pleased with the result, and all I have left to do is mount my motor.

[Neverenoughwatches]

Good feeling when what was seemingly a big issue was resolved easy Michael.  What grade and colour did you use ?

[mbwatch]

5 hours ago, Neverenoughwatches said:

Good feeling when what was seemingly a big issue was resolved easy Michael.  What grade and colour did you use ?

Hi Rich - I used the green 111/Fine, which is labeled for steel, cast iron, hard bronze. Mixed with basic 3 in 1 oil. I paid about $25 delivered for a little 3oz sample tub from a US tool supplier and have enough left to lap every other vintage watchmaker's lathe out in the world.

[Neverenoughwatches]

6 minutes ago, mbwatch said:

Hi Rich - I used the green 111/Fine, which is labeled for steel, cast iron, hard bronze. Mixed with basic 3 in 1 oil. I paid about $25 delivered for a little 3oz sample tub from a US tool supplier and have enough left to lap every other vintage watchmaker's lathe out in the world.

Big watch tool repair made simple and inexpensive, great call Nicklesilver . Might have to get myself a tin. 

[caseback]

Yes, I've used this product on 2 lathes after @nickelsilver's advice.

Works great. The matte finish will possibly help keeping the oil in place as well..