Bench grinder newbie - should I install a shield on the wooden bench top ?

[hawkeye54]

I just mounted a Delta bench grinder on my plywood bench top. Do I need some kind of spark shield under the grinder to protect the plywood from sparks, etc ?





Rick

[P.I. Stazzer-Newt]

The bench top is probably ok, but beware of any dust os shavings....

And if you must grind magnesium or aluminium, clear up before working steel...

[Dave Hadfield]

Yes you do. My Dad had a shop fire once from grinder-sparks ricocheting around.

I take mine outside when I grind metal, and set it up on a piece of plywood over two sawhorses.

[stromborg]

The plywood itself is probably just fine. Watch the stuff around the grinder, little piles of sawdust etc. though I did mange to set a flannel shirt i was wearing on fire once while using an abrasive saw to cut steel.

Welding is another matter, I've burned pants, shirts, the trap room of the Huntington theater....

[hawkeye54]

All good advice so far - I have it bolted down to the bench, was wondering about maybe putting a piece of roof flashing or similar between the grinder base and the benchtop (?)




Rick

[jpatrick]

Every grinder I've used throws the sparks out the rear. So if any protection is needed it's on the wall.

Light duty grinding is fairly safe since sparking is minimal. But if you have plans to really bear down, taking it outside might be a good idea. Besides the fire danger, a lot of metal grinding will be dirty.

Jeff

[wizbang 13]

If you ever use a wire wheel, use eye protection. Not for the crap that the wheel throws off , but for the actual wires flying into your EYEBALLl !!!

[Garret]

If you ever use a wire wheel, use eye protection. Not for the crap that the wheel throws off , but for the actual wires flying into your EYEBALLl !!!

Absolutely - though I extend that to grinding as well. I've had my grinder on wood for a long time, but clean up under it often. I don't usually use it for wood, but keep any sawdust nearby vacuumed before grinding.

[Canoeyawl]

It is a bad deal to lose an eye...
Really bad

[lupussonic]

I have had so many near misses from rotary grinding machines, and had so many friends have bad accidents that I bought one of these. I don't use it for a quick drill sharpen on the bench grinder, more angle grinders and any wire wheel machine. Bruce is spot on about the wire. After stripping down the paint on a machine I was renovating, I pulled half a dozen bits of metal out of my forehead that evening. I have progressed from mere safety glasses.

A colleague recently showed me his, with a piece of 1mm x 5 inch cutting disk stuck in the plexiglass at eye level. That would have been a very bad day had he not had it on. From then on I was converted.

3M-G500-7100029146-Gesichtsschutz-mit-integriertem-Visier-Gelb-EN-352-EN-1731.jpg

The sparks from a bench grinder or angle grinder are many, but they don't have much thermal mass and you'd have to work pretty hard to set fire to anything, unless you were seriously negligent in your house keeping and/or directing a long hard jet of them at something light and combustible for a long time, such as your clothing or a pile of wood shavings. Your ply doesn't need protecting, just be tidy around any hot works and stay vigilant.

[hawkeye54]

Lupussonic, thanks for that timely posting - the relating of the bits of metal in the forehead brought back the image of a co-worker of mine, who was testing phasing of military shore power cables - but with his meter accidentally set on resistance (Ohms) . The meter exploded, sending bits if molten copper at his face. He wore thick glasses, which stopped the bits which would have embedded into his eyes. He kept those glasses as a reminder for a long while.



Rick

[lupussonic]

You're welcome Rick.

Twice I have had microscopic slivers of steel embedded in my eyeball and the pain some hours later was exruciating and needing a hospital visit. Really deeply unpleasant, and both because I did not wear saftey glasses that one time. I shudder to think what any sizeable piece flying at my eye or face at 500 mph might have done.

Martin.

[Canoeyawl]

I wear a face shield whenever I'm running metal working machinery

There are good, better and best face shields. You have to ask, how much is an eye worth?
I use this one, and insisted on everyone in the shop wearing one (I bought one for each of them) if they were doing any machine work, including band saw, drill press etc. grinder, bench grinder especially is a no-brainer.

F2378E1C-04B5-4F51-8F05-E0569A86C011.jpg

When I was a boy just learning this stuff, a friends father was blinded one Saturday afternoon by a bench grinder wheel exploding. Something you never forget. (They were building his car, a father-son project 49 Oldsmobile 88 with a 57 J-2 engine)

[sp_clark]

A colleague recently showed me his, with a piece of 1mm x 5 inch cutting disk stuck in the plexiglass at eye level. That would have been a very bad day had he not had it on. From then on I was converted.

Yikes. Thanks for posting that.

Why the best safety equipment you can find is always better than whatever's at hand, and making a habit of using the best every time you have need of it is worth reinforcing.

A $200 face shield, compared to a $20,000 hospital ER bill (to say nothing of the long term consequences to your body and your sense of well being) shouldn't require a "maybe I should..." answer.

One US$-priced source for that 3M shield & ear protection depicted:

https://bigamart.com/product/3m-g500-industrial-headset/

[Breakaway]

+1000 on eye protection.

Neighbor, Carmine, 70, is a lifelong tile contractor. Cutting a few tiles for a small repair in his own home last year he lost an eye. Says that at work, he always wears eye protection, but this was just little job. He is sorry now.

Not a bench grinder, I know, but same principle.

Kevin

[hawkeye54]

Kevin, it is way, way too easy to put some side pressure on a wet saw blade while cutting ceramic tile - my 'big-box' store used to do some 'complimenary' cuts for Customers some years back - but discontinued the practice .



Rick

[JimConlin]

If you’re concerned about sparks starting a fire, locate a fire extinguisher nearby.

[ShorelineJohn]

As has been stated ear and eye protection is a must. But if you do a lot of grinding, and it much easier for it to happen with a angle grinder but get a leather apron. Those little sparks hitting your new caehartt jeans will put holes in them. You won't see anything until you wash them then you can find holes in the strangest of places.

[hawkeye54]

Good point on the apron in post #18, John - - Thanks !




Rick

[Jim Mahan]

Back to the OP. As an alternative, I obviated the sparks on the benchtop problem by locating my grinder on a separate stand. It's a small cabinet, reclaimed, the top is barely large enough for the base of the grinder itself. I topped it with a scrap section of glue-lam that is just a bit bigger than the cabinet top and very heavy and dense, and it boosts the height a couple of useful iches. It isn't fastened so I can flilp it or rotate it if necessary. I inherited my grinder, as opposed to choosing one to buy, and it came with rubber feet, so I left it just resting on the stand as opposed to bolting it down, and the whole arrangement is heavy enough to not move. Because of the factory shields around the wheels, the hot grinding residue lands below instead of blowing out the back. I replaced the factory tool rest on the coarse side—because it broke when a thing I was grinding kicked and bounced and kicked—with a scrap of steel to get a bigger referencing plane for dressing a part. Open shelves below the grinder for the supplies you might want handy for grinding work, alternate wheels, an abrader for flattening the working surface. I'd prefer to have more elbow room around the stand.

[Garret]

Back to the OP. As an alternative, I obviated the sparks on the benchtop problem by locating my grinder on a separate stand. It's a small cabinet, reclaimed, the top is barely large enough for the base of the grinder itself. I topped it with a scrap section of glue-lam that is just a bit bigger than the cabinet top and very heavy and dense, and it boosts the height a couple of useful iches. It isn't fastened so I can flilp it or rotate it if necessary. I inherited my grinder, as opposed to choosing one to buy, and it came with rubber feet, so I left it just resting on the stand as opposed to bolting it down, and the whole arrangement is heavy enough to not move. Because of the factory shields around the wheels, the hot grinding residue lands below instead of blowing out the back. I replaced the factory tool rest on the coarse side with a scrap of steel to get a bigger referencing plane for dressing a part. Open shelves below the grinder for the supplies you might want handy for grinding work, alternate wheels, an abrader for flattening the working surface. I'd prefer to have more elbow room around the stand.

I hope you move the Dewalt charger! Filling it with abrasive & metal dust will not do it any favors.

I've never had a grinder that would handle not being mounted (or at least clamped). You must be a kinder gentler sorta guy...

[Andrew2]

Not mentioned yet is something I was told forcefully as a child. Do not grind soft metals like brass copper or aluminium. The 'swarf' clogs the wheels and can cause a crack, shattering the wheel. Chunky bits going everwhere at speed! The casing should contain most, but the open bit is facing you.

[The Q]

Eye protection, yes,
But don't forget lung protection,
Breathing in assorted metals, carborundum and other dust will give you a good case of miners lung.

Set fire to my overalls once, noticed my knee getting warm, while I was using an angle grinder, luckily the overalls were padded at the knees and I had trousers beneath..

[hawkeye54]

Keep those suggestions coming, folks - it IS appreciated. I am not good at posting photos, so let me describe what I have : I have an "as-new" Delta 23-196 grinder that I bought 'for a song' when a store was swapping out store displays. I have it thru-bolted to my benchtop ( doubled 3/4" plywood ) with rubber washers and rubber feet to dampen vibration . Both wheels are new as-built. The bench top is mounted on store demonstrator display base cabinets.



Rick

[willin woodworks]

don't try to grind chain....