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Grinding wheels

Darlene

>I don't think grinding wheels are unsafe, providing all of the correct safety precautions are taken. One of the things that Norton has pointed out recently, is to ensure you get your wheels from a reputable supplier - someone who takes care of their products and would not sell something that has been dropped and damaged. You can check a wheel for cracks before mounting it on a grinder by supporting the wheel on your finger inside the bushings, without touching the wheel it self with your hand, flick the outside edge of the side of the wheel with your finger and you should hear it ring. If you hear a dull sound instead of a ringing sound, then the wheel may be cracked internally and should be discarded. Instances of wheels exploding are relatively rare and there are times when wheels are more advantageous to use than belt grinders (ie for hollow grinding of chisels, as already pointed out), and vice versa.

Darlene

Fascinating technology NM

David Charlesworth

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Cool! Thanks for sharing this!

Scott Burr in Ben Lomond CA

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Re: Grinding wheels

thomd

>Good point. I've heard that one, though it's like anything in glass: helps to know it's not already in pieces, but it still may break.

It's like a lot of things: is the distribution of tragedy purely even regardless, or can you through experience reduce your risk. If the latter, then the person who: wears safety equipment; maintains the gear; buys proper wheels; runs them at proper speeds; profiles the wheels; keeps them sharp; uses a balancing kit; has a soft start; and most important of all knows how to avoid catches, should be pretty much immune.

Then you have to accept that there is a wide range of workers out there, some of whom represent the best there are, and many who have little native ability, training, and not much control over working condition.

Be well and prosper.

Re: Grinding wheels

John in Kerville

>I had one explode on me about 10-12 years ago. Luckily it made a strange noise that warned me something was amiss and I got out of the shrapnel area just in time. I didn't even try to hit the switch just jumped back.

It dang sure gets your attention. Belt sanders or by hand ever since.

Re: Grinding wheels

thomd

>Good that you are all right!

I learned to grind from one of Richard Raffan's early videos, and he grinds mostly freehand, and one needs to be to the side to see the bevel contact. An advantage is that one is less likely to be hit with junk should the stone break. Something I keep in mind when using good rests etc... where the rest does the alignment but often one stands right in front of the grinder.