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I’ve got a hand-held angle grinder (Makita LXT, 5”). I’m using a wire brush in it to finish a long thin bit of steel (rectangular profile, about 3ft long, 5x15mm tapering to 5x5mm - it’s a sword blade, but it’s not sharp, so that’s probably not relevant)

It’s proving difficult to clamp the workpiece as it’s very thin. (Before everyone suggests ways to clamp it - I’ve got a metalwork vice, but I’ve not got anywhere to fit it outside where I use the grinder, so I’m using g-clamps. Also clamping round the part I’m working on means the grinder is mainly in contact with the clamp, which wastes effort and makes controlling the grinder harder. It’s difficult to grind beyond where it’s clamped as it resonates. So the most effective method has been clamping either side of the part I’m working on, but this is difficult).

I think it’d be easier if the grinder was fixed, and I brought the work piece to the grinder - I’d be able to hold it either side of the part I’m working on, and to feel the movement of the workpiece and compensate.

However, I’m conscious that this isn’t what the tool was designed for, but I know bench grinders do exist (I don’t have a bench grinder), and I think they give more control (which i presume is why they’re used for sharpening knives etc). Is this approach safe? If so, are there any precautions I should take?

Dan W
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I do not think anyone should recommend that someone try clamping an angle grinder to a table rather than buying the correct entry-level tool (a bench grinder).

While clamping an angle grinder to a table could probably be done, the effort and skill required to make a clamping jig that reliably holds an angle grinder in place is high and the risks of doing it wrong are even higher. The jig likely requires wood or steel working tools where you would have already had a bench grinder in your shop for years before buying the tools required to make a jig to clamp an angle grinder.

To outline the risks: Basically, if the grinder comes loose while you are working with your fingers next to it, then your fingers are instantly a mangled mess either by the blade or by getting them crushed in the spindle.

statueuphemism
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I have a cheap angle grinder, and clamping it would be a pain. However, it came with a screw-in handle and holes on 3 sides. I have quite often put the grinder up against some other surface (my welding table, or a set of metal sawhorses I have) that has a convenient hole, screwed the handle through the hole, and then tightened the crap out of it. It never comes loose and I've never had any issue with it moving. (The entire sawhorse walking around is a different issue.)

user34314
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Safe? Probably not the safest. Should you do this? Probably not, and if you do, do it at your own risk. I don't know what grinder you have, but the biggest risk here is to have something caught in the wire brush, like your clothes. To be safer, you should use a grinder that the ON button has to be held down in order for the grinder to work, rather than a SWITCH that stays ON or OFF. This way, you can clamp the button as well for example, so in case the grinder falls, or perhaps even moves, it shuts OFF. If you have to do something stupid, you have to think it through as much as possible. That being said, I have done this. Its one of those things you do because you have to but would never recommend to anyone.

riseagainst
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Since you ask about precautions: If you mount the grinder get some heavy leather gloves, I have lost skin a few times even with gloves on while using a bench grinder when the wire wheel grabbed the part and pulled my hand into the wheel , if I would not have had gloves on the damage would have been severe. The biggest problem is you won't have a platform to support the blade, it still may be workable just make sure not to let the leading edge of the piece get caught in the wheel only work the bottom 1/2 surface , flip and then the half, turn end for end and repeat, don't use much force and keep your hands away from the wire wheel. These are the precautions I try to observe on a wire wheel in a bench grinder.

Ed Beal
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Is it safe? No, not really. Have I done it myself? Yes, as a metal worker in the army. (Didn't have a bench grinder on hand)

Though not recommended, if you are going to do this be careful. Wear some thick leather gloves in case something does slip loose. I used my welding gloves. (I shouldn't need to mention eye protection) Mind how much pressure you're putting behind your work piece on the grinder as to not dislodge it from the vise. That grinder could be spinning from 10-15k rpm and would make your skin look quite messy.

Phaelax
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Just to add another point: for most purposes that involve a fixed grinder, a slow speed is preferable to a high speed. For example, if you are sharpening a blade you don't want to heat it so much that you take the temper out of the blade; that's much easier to control with a slower speed grinder, and you may want to go as far as using a water cooled wheel.

Also, unless you are removing a great deal of metal, remember that whetstones still work.

keshlam
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