# Help with Boyar Schultz 618



## Options10 (Aug 19, 2022)

Hello all,

I’m new to the forum and hope somebody here can provide some information. I have a  new to me Boyar Schultz 618 surface grinder. The X axis hand wheel was loose and flopping around. I was able to remove the hand wheel assembly but I don’t know how to remove the gear wheel and inner shaft. I also need information on what bearings are required at each end. Any help would be appreciated.


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## T Bredehoft (Aug 19, 2022)

With any luck, the old, beat up bearings will have numbers etched on them, which when ordered will replace the old bearings.


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## Richard King 2 (Aug 20, 2022)

I checked out Vintagemachinery.org and found this one.  My internet is slow, so you can look on your own.  http://vintagemachinery.org/pubs/2682/4860.pdf


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## Richard King 2 (Aug 20, 2022)

It looks like you will need to bore out the hole and press in a bronze or nylon bushing.


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## Options10 (Aug 20, 2022)

Thanks Richard, that’s a big help. Much better detail than the reproduction manual I purchased. I’ll have to do more searching to identify the parts by number in the illustrations. 

My next challenge is removing the pinion gear from the shaft to access the housing. 
I’d love to hear from anyone with first hand experience with this.


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## Richard King 2 (Aug 21, 2022)

Clean up all the surfaces of the gear pinion.  I have removed parts off of many brands and I used to rebuild B&S when I was an apprentice.  They are simple as far as a machine.  I can't remember exactly though, but it can't be that difficult.   I suspect there is a tapered pin holding it to the shaft  It goes out then big bored hole.  You need to be a detective and figure it out.  If your mechanically inclined it should be a breeze.


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## Richard King 2 (Aug 21, 2022)

Look at page 11 and part 61 and 62.  That is a taper pin holding the rack pinion on.  Use a veneer to measure the small end of the hole, don't eyeball it as usually you guess wrong.  If you can't tap it out, drill it out.   But as I said.  Be a detective and figure it out after you clean everything up.


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## Cadillac (Aug 21, 2022)

It is a tapered pin. It should be fairly easy to locate. At least mine was mine seemed wobbly on the shaft. Replacement gear and rack can be had at McMaster Carr. You would have to drill mounting holes in rack. Bearings can also be source through McMaster, if I’m not mistaken their is a bushing in the casting?


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## Options10 (Aug 21, 2022)

Yes, there’s a tapered pin, my next task. There is what’s left of a bushing on the handwheel end and a trashed needle bearing on the gear end. Looks like the drawing shows an additional needle bearing in the housing.


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## Options10 (Aug 21, 2022)

The manuals that Richard referred me to are a huge help. McMasters is new to me but it looks like they have several bearing/bushing options available that might work. I don’t think I necessarily have to duplicate the original engineering, I may just have to re-engineer it to make it work. Might be an improvement using modern materials. I’m starting to believe this is a viable undertaking.  More questions to come, no doubt.  Thank you all for your help!


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## Cadillac (Aug 21, 2022)

I double up the needle bearing to cover more surface on the shaft. It’s already machined for it.


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## Richard King 2 (Aug 22, 2022)

Needle bearings are cheap, be sure to use the inner hardened roller.  Todays plastics like Delrin or Nylatron could also be used.  Give it some clearance  on the id like .002".  No need to press fit it. A sliding OD with some green loc-tite to anchor it.


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