Boyer Shultz 6x12 rebuild

Cadillac

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Just wanted to start out by saying hi this is my first posting on here. Hopefully more informative and less cockiness then the "professional site". It's always a pissing match over there. Anyways.
I recently purchased a Boyer Shultz h612 challenger. Seems like a good unit for the price. So in my nature I completely disassembled the machine to clean,survey,and replace as needed. Spindle bearing felt gritty so I removed spindle housing. Read up as much as possible to get insight on what was to come. I read a fella made a nice fixture to hold the spindle on the flat just behind the taper so I made that. He also made a 4 pin socket to fit rear nut. I also made that. I had sprayed some pb blaster on a hour or so before. I put my fixture on spindle put the socket on rear nut. Expecting to put some force on it the nut spin right off. Maybe 10 ft lbs to take off. Surprised me would have thought more toque on that nut. Another surprise was instead of two bevel washer back2back like 99% of the people if read had. There are two ground spacers with like 8 pockets on one side each. The pocket faces are facing each other and have springs in each pocket. So it's a spring Assy for preload. Just not what I expected? Hopefully bearings clean up that's the plan.
So I figured I would tear the Boyer Shultz electric motor apart to clean and grease them 45yr old bearings. Their are 6203 z nsk hoover bearings made in USA stamped on them. Going on nsk site they say that a 6203z is shielded one side. Zz is both sides. Mine are both sides with only a single z. My question is can I just put a sealed bearing in its place same specs otherwise.? I want to grease the originals but one shield would get dimpled in the process. And they're cheap enough just replace which I have sealed on the shelf just not shielded. Other than regressed or replace bearings motor looked pristine inside.
As for the grinder I didn't take any measurements yet to see if it's gonna grind flat. It was filthy and I always disassemble every piece I buy to first go through it too see condition and replace or fix anything that's wrong with it. It's also a sickness but 9 1/2 out of 10 times I have something better than original for pennies on the dollar. It's gonna need the bellows for the lead screw so a source of those would be great also. I'm gonna wait to see when I put everything back together and hope for the best on how flat she grinds. Ways look okay. Some flaking still visible but fades closer to operator. The table looks to have hardened ways and the mating surface looks good so fingers crossed. I'm not a big fan of repainting the machine unless your gonna strip off all old and give it what a real paint job deserves. I'm actually a fan of a 100% clean degrease and leave the factory paint. Gives it character to me. Fortunately all my machines aren't abused so scratches and wear marks are minimal.
I'll ty and post some pictures of her when done I haven't looked into loading pictures on the site yet. Thanks in advance for any comments or insight you might have on repairs.
 
congrats on the grinder!
i'm a recent owner too.
i'm still learning about the unit, but they are nice to operate!
 
Just wanted to start out by saying hi this is my first posting on here. Hopefully more informative and less cockiness then the "professional site". It's always a pissing match over there. Anyways.
I recently purchased a Boyer Shultz h612 challenger. Seems like a good unit for the price. So in my nature I completely disassembled the machine to clean,survey,and replace as needed. Spindle bearing felt gritty so I removed spindle housing. Read up as much as possible to get insight on what was to come. I read a fella made a nice fixture to hold the spindle on the flat just behind the taper so I made that. He also made a 4 pin socket to fit rear nut. I also made that. I had sprayed some pb blaster on a hour or so before. I put my fixture on spindle put the socket on rear nut. Expecting to put some force on it the nut spin right off. Maybe 10 ft lbs to take off. Surprised me would have thought more toque on that nut. Another surprise was instead of two bevel washer back2back like 99% of the people if read had. There are two ground spacers with like 8 pockets on one side each. The pocket faces are facing each other and have springs in each pocket. So it's a spring Assy for preload. Just not what I expected? Hopefully bearings clean up that's the plan.
So I figured I would tear the Boyer Shultz electric motor apart to clean and grease them 45yr old bearings. Their are 6203 z nsk hoover bearings made in USA stamped on them. Going on nsk site they say that a 6203z is shielded one side. Zz is both sides. Mine are both sides with only a single z. My question is can I just put a sealed bearing in its place same specs otherwise.? I want to grease the originals but one shield would get dimpled in the process. And they're cheap enough just replace which I have sealed on the shelf just not shielded. Other than regressed or replace bearings motor looked pristine inside.
As for the grinder I didn't take any measurements yet to see if it's gonna grind flat. It was filthy and I always disassemble every piece I buy to first go through it too see condition and replace or fix anything that's wrong with it. It's also a sickness but 9 1/2 out of 10 times I have something better than original for pennies on the dollar. It's gonna need the bellows for the lead screw so a source of those would be great also. I'm gonna wait to see when I put everything back together and hope for the best on how flat she grinds. Ways look okay. Some flaking still visible but fades closer to operator. The table looks to have hardened ways and the mating surface looks good so fingers crossed. I'm not a big fan of repainting the machine unless your gonna strip off all old and give it what a real paint job deserves. I'm actually a fan of a 100% clean degrease and leave the factory paint. Gives it character to me. Fortunately all my machines aren't abused so scratches and wear marks are minimal.
I'll ty and post some pictures of her when done I haven't looked into loading pictures on the site yet. Thanks in advance for any comments or insight you might have on repairs.
Hey Cadillac! First learn how to spell "Boyar Schultz", or nobody will believe you have one. ;) It would probably be best to use double sealed bearings (SS) instead of the shielded ZZ bearings. They keep the grease in and the grit out. Just make sure you buy good quality ones, NOT the cheapest ones on eBay for sure! Those machines are complete orphans, so no factory parts are out there except perhaps some NOS parts that have been laying around for decades. Still, though, they probably used mostly standard hardware and common stock for most of their parts. See if you can find a user group for your grinder. Wait, let me do it, I know how to spell the name, and I don't even have a machine badge to copy from. :) Start looking here:
https://www.bing.com/search?q=boyar...7D7245C92B4980B8A499DBE0F8A623&FORM=QBRE&sp=2
Sorry, no luck on a user group or parts sellers that specialize in Boyar Schultz surface grinders...
If you do not have a parts and user manual, look here for free downloads: http://vintagemachinery.org/mfgIndex/detail.aspx?id=2682&tab=3 Edit: having the part numbers helps immensely when you are looking for rare and obsolete parts. Search on "Boyar Schultz" followed by the part number(s) you are looking for...
 
Thanks for the response guys. I’ve already downloaded all the manuals I can find.
So you say don’t get cheap bearings. If I order from a grainger or McMaster will those be quality. I really don’t understand this bearing stuff. I am a heavy equipment mechanic. When I order bearings I go by numbers on races along with measurements. I know their are different grades but if I order a 6203z shouldn’t I get a 6203z where is the grade in that number. I thought a 6200 series was a single deep groove bearing. And all are a class 3. Am I wrong with that assumption??? What class would the 5 dollar bearing be on eBay a knock off??? I’m not cheap and am more than willing to pay to play.
Here’s a picture of spindle Assy. Anybody ever see this style of preload spring on the boyar Shultz. All the pics I’ve seen had the double Belleville washers back to back. Thanks again. image.jpg
 
Welcome Cadillac
Your grinder is a newer version than mine. I've seen the spring preload design before but mine doesn't use that. The grease in my bearings was dried out, after wasting them out I repacked them and they seam to be running fine. Did take a bit of flack at the timefor attempting to service a precision bearing though.
The bellows on my cross feed were shot too. This may seam a bit of a back yard hack but I made coil springs from piano wire then slid a bicycle inner tube over them and fixed the ends. Seams to be working fine. Had no idea where to source bellows.
If they used shielded bearings on the motor they may have had a reason. Wonder if fine grinder grit might wear the seals prematurely. If the originals are still smooth I'd be tempted to pop the shields and wash and repack them.

Greg
 
Thanks for the response guys. I’ve already downloaded all the manuals I can find.
So you say don’t get cheap bearings. If I order from a grainger or McMaster will those be quality. I really don’t understand this bearing stuff. I am a heavy equipment mechanic. When I order bearings I go by numbers on races along with measurements. I know their are different grades but if I order a 6203z shouldn’t I get a 6203z where is the grade in that number. I thought a 6200 series was a single deep groove bearing. And all are a class 3. Am I wrong with that assumption??? What class would the 5 dollar bearing be on eBay a knock off??? I’m not cheap and am more than willing to pay to play.
Here’s a picture of spindle Assy. Anybody ever see this style of preload spring on the boyar Shultz. All the pics I’ve seen had the double Belleville washers back to back. Thanks again. View attachment 264019
The grades of bearings has to do with their dimensional tolerances. I have seen people drill through cheap import bearings, making a nice curled chip. I have seen the races squeezed flat in a vise without failing. Junk. The part numbers of bearings are anything the manufacturer or importer wants to use. There is no regulation and enforcement of bearings. Whatever standards do exist are agreed specifications agreed among bearing manufacturer associations, and the junk bearing makers and sellers are not members. There are also counterfeit bearings out there. Buy good quality bearings from a trusted source for applications you really care about. Surface grinder bearings are high on that list.
 
Bellows can be found at McMaster Carr in different sizes

as far as bearings go ABEC3 bearings are normal off the shelf general purpose bearings
ABEC5 will be a more precision grade, ABEC7 will be even better yet but they get very expensive as the grade of bearing goes up

i would also second Bob Korves suggestion of using SS (double seal) rather ZZ (dust shield) bearings for this application
 
There should be bearing retailers in your area. Might be under power transmission.
You can check with them for cost to make a decision.
Hope you can find a torque spec for the spindle nut.
 
+1 on all that has been said so far.

Because of all the work you are putting into the machine, it would be a waste to put in cheap bearings. Because they are a fairly small and common size, I'd guess that even the best you can obtain won't break the bank. In the Frozen North we can go to FAG bearings directly, and be sure we have great bearings.

Good luck on the rebuild!
 
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