bench grinder wheel alignment

Another newbie question...
I purchased a cheap Chinese-made bench grinder to make lathe bits with.
(The alternatives I found at the time were more expensive but didn't look
significantly different, until I got to the $300 mark, which seemed absurd
for my minimal needs.)
The grinding wheels are way out of true; they wobble from side to side as
they turn, by about 0.1" over 180 degrees. It's not that the wheel itself
is bad; it seems that the flanges that clamp the wheel in place are not
square to the shaft, so they force the wheel to be at an angle with the
shaft. I did try replacing one of the wheels with a higher quality wheel
but it made no difference; that's when I realized what the problem was.
The shaft itself just has a little (~ 1/16") lip to support the mounting
flanges, and the flanges themselves are just pressed parts, so it's not too
surprising that they aren't square.
My questions are these:
1. Is this actually a problem, in practice? I'm thinking it would make it
very hard to use the side of the wheel (like to grind a boring tool) but
maybe I'm wrong.
2. What's the best way to fix it? Should I turn new flanges, add something
around the shaft to give the flanges more support, give up and buy a more
expensive grinder ...?
Thanks yet again.
Reply to
Walter Harley
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Way too much runout to be usable.
Take it back to exchange for another. If the 2nd is similarly bad, then forget it.
Reply to
Richard J Kinch
Yes. You can't really work with a wheel that wobbles like that, and running it that way significantly increases the chance of catastrophic failure.
Replace the flanges with something that works. Second best solution is probably to machine the punched-out flanges you have. This should be short work on the lathe and ought to be ok as long as you don't have to remove more than a few thou from any face.
By the way, grinding on the side of a Type 1 (straight) wheel is discouraged by the manufacturers.
Reply to
Jim Wilson
That much wobble is hazardous and completely unacceptable.
Check the shaft for radial runout and eccentricity. Does it vibrate when running without a wheel mounted? If the flanges were that crummy I'd suspect the rest of the machine as well.
If radial runout is OK, turning good flanges should do the trick for you. I don't have any stamped flanges on my grinders; they're all shop-made on the lathe.
Reply to
Don Foreman
Turning hefty new flanges with the inner flanges interference fit to the shaft is the best improvement that can be made to inexpensive grinders. My experience is that wheels will not stay true with the original stamped flanges that seem to come with most cheap and intermediately priced grinders.
Reply to
MP Toolman
Reply to
Charles Kroon

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