Surface Grinder for a hobbyist

Ok, based on what I found for nuts and I think I'll run it the way it is for now and work on my threading skills.

I got my vfd today and wired it up. Does this sound ok? Although it's not bolted to the stand at the moment, and the stand is sitting on a pallet.. probably not the best setup.

I am expecting the mag Chuck and new wheels on Wednesday.
 

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Ok, I've pulled much if the machine down inspecting and cleaning and the only thing I found that actually concerns me is the cross feed leed screw is very badly worn. The accordian boot covering it broke and looks like it's worn the screw down to pretty sharp points in a section.

I don't have the proper guages but I think the shaft is 3/4-10 lh square thread. Anyone know.

I was looking at McMaster but the design of this screw is weird, it's not fully threaded, only about 2/3 is then the thread just stops, not even a relief cut, with the rest of the shaft at a full 3/4.

Open to suggestions. My current thought is to get some 3/4 crs from my local hardware and see how many tools I can break and how many hours I can waste trying to cut a thread I've never cut before, over about 14" ....

I wouldn't worry too much about wear in the cross slide (at least until you have used it for a while). The cross slide gives you the amount of shift over per pass. For example if you are cleaning / truing / flattening a 1" wide surface and say you have a 1/2" wide wheel - then you may choose to step over by 0.05" per pass. It really does not matter whether you step over 0.04 or 0.06 - the wear in the cross slide lead screw will not impact how flat the surface is.

If you are grinding to corners, then it would be nice to improve the cross slide - however, even all new components will still have backlash - so I suggest there is little to gain by having consistent backlash over across the entire slide.

For the fabric way covers, I used neoprene coated nylon fabric from McMasterCarr - works great.
 
Thanks chipper, funny you gave that advise.. me being who I am stuck the machine back together after I connected the vfd, put an old drill press vise under the wheel and proceeded to do my first grind (cleaning up the top of the vise). I was taking between .025 - .100 step over, with .002 - .004 doc. The backlash didn't affect me at all.so at this point I'm going to reclean the top and replace the way covers., Then run it ...
 
Ok, this shaft has a lot of slop in it. I'm not sure if I have the capability to fix it as I think its the housing. Anyway, I've removed two set screws but cannot figure out how to remove this shaft for a better inspection.
 

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driveslayer, when I brought my Boyar home, I took all of the covers off, the table off, and the cross slide off to clean the gunk out (what a mess!). Also spent a fair amount of time trying to clean out the oil lines, as half of the Bijour jets were clogged. I ended up replacing all of the jets and one fitting I broke. Make sure you have oil everywhere before you put it back together. The cross screw bellows was shredded on mine, so I found a length on McMaster for about $100 and cut it in half. Like yours mine a fair amount of wear on the ways with most of the flaking gone (put still had original oil groves), so I added new marks/pockets with end of sharp file before assembly.

My cross screw had about .025 play when assembled, so I left it alone to wait for for another day if the rest of the grinder proves worth the trouble. That play does not affect the repeatability of the cross slide at all. In 20 years as tool & die maker I never once used the cross feed screw to dial off a large number (like 3.0500 inches) and expected it to be accurate anyway. That screw is just a guide, so don't worry about any play. Keep it clean and oiled and will last forever in home shop.

I did replace the rubber covers with new ones made from rubber sheet at McMaster. The left - right travel of the factory machine was 12.5 inches, so I spent some time with the factory stops and hand ground some material away. I now have 13" of travel, a bit easier to get the wheel completely off the chuck without hitting a hard stop when grinding the chuck.

My spindle makes some loud noise periodically (typically whenever my head is down and looking in at wheel from the side!), but for most part it is reasonably quiet. Not as quiet as it should be, so maybe some day I will take it apart, clean the old gunk out of the bearings, re-grease and assemble. For right now, I would not be without the machine. Even half worn out, it adds a level of precision that you just can't get from a lathe or mill.
 
To remove the traverse handle take out the set screws like you have. Then take the gear off the one end. I believe it’s a tapered pin holding the gear. Once the screws are out you want to tap the shaft towards the handle. It’s a slide fit in the apron. If I remember correctly the set screw will hold the shaft like a lock so the table locks in place. I had ordered a new rack and gear from McMaster which was Almost a direct replacement except that I had to drill holes in the rack for mounting.
You can get most of the parts from McMaster which are near oem replacements just might take some slight modifications. I wouldn’t worry about the apron screw unless your grinding up to a edge which it will still be accurate just a pain with the backlash.
 
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