Walter Harley writes:

1. Is this actually a problem, in practice?

Way too much runout to be usable.

Take it back to exchange for another. If the 2nd is similarly bad, then
forget it.

Walter Harley wrote...

I purchased a cheap Chinese-made bench grinder to make lathe bits with.

...
the flanges that clamp the wheel in place are not
square to the shaft ...

1. Is this actually a problem, in practice?


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.

2. What's the best way to fix it?

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.

Jim

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.

On 17 Aug 2004 23:33:14 GMT, "Walter Harley"
wrote:

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.

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.

Mill

Subject: bench grinder wheel alignment
From: "Walter Harley"
Date: 8/17/2004 7:33 PM Eastern Daylight Time
Message-id:

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.

Don Foreman wrote:
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.

On 17 Aug 2004 23:33:14 GMT, "Walter Harley"
wrote:


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.