Exploding Grinding Wheel

[old martParticipant @oldmart]

I bought a bench grinder last year from Lidl, the type with one end geared down to about 120rpm with a large wet wheel for wood chisels and plane blades. That is too slow to be dangerous except for trapping fingers. The full speed wheel at the other end was removed and binned and a mandrel for a 100mm electroplated diamond wheel. This is made from aluminium and cannot shatter. The grinder has been mounted on an aluminium base with an adjustable rest for the diamond. These diamonds can be used for HSS, but as steel will cause chemical decomposition of the diamond, the life will be reduced. For limited home use, it probably wouldn't matter much.

For grinding wet, the rule always to be observed is that you must turn off the coolant before the wheel. This ensures the wheel is pretty much dry before it stops turning. If the wheel is stopped while wet, the coolant will end up at the bottom of the wheel as it slowly drains away, and the wheel will be very out of balance when starting up.

[Neil WyattModerator @neilwyatt]

Posted by Plasma on 30/06/2020 08:33:50:

We always ran the stone a few minutes with the water tank empty to dry it out at the end of the day. Amazing to hear water shooting off the stone from the portion that had sat in water as the trow was drained.

Out of curiosity, in what part of the world did you grow up?

My grandmother grew up on an Oxfordshire farm and always called a trough a trow, but I've never heard anyone else use the word.

Neil

[Neil WyattModerator @neilwyatt]

Yes, please avoid getting into the politics of Covid-19. Rather than have a discussion here anyone interested in the statistics can visit the link below which offers figures without any interpretation .

Neil

http://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/deaths/bulletins/deathsregisteredweeklyinenglandandwalesprovisional/weekending19june2020

[andrew lynerParticipant @andrewlyner71257]

Posted by Nicholas Farr on 30/06/2020 10:36:19:

Hi Andrew, please don't get complacent about the size of your wheels, as the smaller diameter of the wheel, generally will spin faster than a larger one. As it is the peripheral speed that counts, bits flying from it will be very much at the same speed, it's just the mass that will probably be significantly different.

Regards Nick.

Edited By Nicholas Farr on 30/06/2020 10:37:10

Never complacent about anything whirring round.

Since my new white wheel arrived I don't even have to press hard to shift metal so there's even less stress (mechanical and mental)

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