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Grinders and sanders


Well-Known Member
Nov 20, 2006
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My workshop is coming along. I'm looking to buy a grinder and a sander and need some input please.
(1) I was originally considering getting one of those combo belt and disk sanders, but I read that the 1/3 hp motor that they tend to come with is pretty small and willtend to stall with pressure. I'm thinking instead of just getting a 1 hp 12" disk sander, which I presume I'll use more than the belt anyway. Do I need a belt sander? They tend to be pretty narrow unless you're willing to pay a lot. Keep in mind that the airframe will primarily be steel and aluminum. Not much wood.

(2)Do Ineed anything larger than a 6" grinder?

(3) What grits ofgrinding wheels and sanding disks will I need for the grinder and sander?

(4) If I'm to keep the grinding and sanding separate for aluminum and steel, howis this usually handled? Iassume thatpeople don't tend to have duplicategrinders and sanders, one for each material. Do you just keep switching the sandpaper or grinding wheel? What if Ialso want tosand the wood every sooften; I've heard the recommendation herenot to machine wood and metal with the samemachine due to sparks? Is itjust a matter of vacuming out the saw dust first?

(5) What composition should I look for for the grinding wheels and sanding disks? I understand that aluminum oxide is a bad idea for steel because it will accellerate corrosion; what about silicon carbide on steel,would that addcarbon and change the material properties? Are there other compositions available?

(6) I'm planning on using these tools mainly for shaping, and to use a Scotch Bright wheen for buffing the edges of the parts. Is this realistic or the best way to do things?

Finally, in the spirit of not holding back potentially silly questions,what tasks are better performed on the grinder vs. the sander?


PS. My first workbench is complete. I've got a Bingelis rolling tool support in progress for mounting these tools and a drill press. I'm gettinga 220 Voutlet or two installed soon so I can buy a decent-sized air compressor. Now I need some metal to cut. :)

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