Sqeeeeeeky Eclipse Permanent Magnet Surface Grinder Chuck

[itsme_Bernie]

Thanks Jim- I think I may be brave and start with light cuts and see what starts happening. Right now I mic a four inch long part 1/2 thou bigger at one end. I think I do better than that!

Bernie


Bernie

 

[JimDawson]

Once everything is dialed in, I would expect 0 difference. After grinding the table you may also want to grind both the base and the top of the chuck.

 

[rgray]

Stone the table to get an idea of high or low spots. If you have not ground the chuck and you are only .0005 off that is real good. Use coarse wheel to grind the chuck, relieve the wheel in the center section so only the outer edges contact the chuck. I use a round stone the size of a pencil for that. Mark the chuck with pencil lines so you can see where the grinding is and watch progress, don't use dykum.

 

[brino]

I think it just mikght be better to live with the squeak than to risk filling the chuck up with some fluid that might harden over time,or do something else that eventually ruins the chuck.

Agreed....to a point. As Bernie says the squeak alone is not the real problem, the mechanical resistance and the feeling that you could be bending/breaking something is.

If it's that hard to operate it has likely already been filled with fluid...perhaps a water based coolant that could separate over the years.

My soaking recommendation was more about getting those two screws on the back loose. Hopefully Bernie can find a manual and see if that is truly a way in.

However, even if he cannot open it I'd rather have some ATF/acetone mix in there with the coolant....

-brino

 

[george wilson]

How can you grind the table? Do you mean to grind the table IN SITU?? Does the grinder have enough travel to completely clear both ends of the table?

I'd advise just stoning off the high spots and dings as suggested. I use a file rather than a stone myself. If you look down a flat,ordinary file,they are seldom flat. They have a little bend in them. Use the convex side of the file to file off the dings. Some files are S shaped rather than simply curved. I reject them except for ordinary file work where the warp doesn't matter. Back when you could buy a file UNWRAPPED,I rejected them out of hand. Now,the blasted things come in plastic so you can't see their warp. And,the Mexican Nicholson files are soft as butter. I hope some day they figure out how to not let them decarb while hardening them. You can take an OLD USA file,and easily file the corner right off a Mexican Nicholson. After about 1/32",you finally hit he hard core. But,the teeth are very soft.

 

[itsme_Bernie]

Great! That's what I was thinking!
I'll let you know how it goes

Bernie


Bernie

 

[itsme_Bernie]

Stone the table to get an idea of high or low spots. If you have not ground the chuck and you are only .0005 off that is real good. Use coarse wheel to grind the chuck, relieve the wheel in the center section so only the outer edges contact the chuck. I use a round stone the size of a pencil for that. Mark the chuck with pencil lines so you can see where the grinding is and watch progress, don't use dykum.

Thanks man! I will do that. I didn't know about the relieved wheel.

For now, I had some serious cleaning up to do on the table. I took .010 in off and I still have about .0005 to go!

I took it all off, and it barely changed temperature. I will let it sit for a few hours or a day and let it all settle anyway. I know milling can change the stresses in the workpiece, and despite the table being stable cast iron, I'm going to be crazily particular.
Then I'll re-dress and relieve the wheel like you suggest and do the finish skimming.

Here's where I'm at so far:




Bernie

 

[rick9345]

Try this Guys site,does a lot with surface grinders.
Some place in one of the videos he redid a magnetic chuck
https://plus.google.com/u/0/+ShadonHKW/posts
I too have a small Sanford (3 x 6). Works nice, now want a bigger one.

 

[hdskip]

Boy this brings back memories. I'd rather take a beating with a big stick than grind a magnetic chuck. I've done it many times when I made my living on a surface grinder. I now use a small magnetic transfer block and grind it as I need it. It keeps me from contemplating dire things when I need to have a flat spot to grind on. The small area of the block saves the wear and tear on my bad rotator cuff on the manual grinder.

 

[JimDawson]

Boy this brings back memories. I'd rather take a beating with a big stick than grind a magnetic chuck. I've done it many times when I made my living on a surface grinder. I now use a small magnetic transfer block and grind it as I need it. It keeps me from contemplating dire things when I need to have a flat spot to grind on. The small area of the block saves the wear and tear on my bad rotator cuff on the manual grinder.

That is why the power feed was invented. I've done the same thing too many times. I'm getting ready to do a full CNC conversion on my DoAll, no more cranking!!
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