Dremel Grinding Bits--What Do I Need?

[Snake45]

I need to grind some aluminum, and also some resin (different projects). What type of Dremel grinder bits are best for these? I've had aluminum just pretty much "plate" a grinding stone in a Dremel before, and had resin melt and gum up cutting-type grinders.
 

[935k3]

The diamond rotary set from Harbor Freight is what you need. You can get a 20% off coupon.

http://www.harborfreight.com/50-pc-diamond-rotary-point-set-69665.html

[Ace-Garageguy]

For shaping aluminum ,you may find that real tungsten-carbide burrs avoid the loading common to grinding. It will depend on the alloy you're working with to a degree too. Lube 'em and they'll last just about forever.

Also, you MAY find that an occasional lube with a bar of paraffin wax or even bar soap will keep your saw blades and grinder discs from loading so fast. A squirt of WD-40 may also work.

I keep a bar of soap on my band-saw for just such operations. Works a treat, saves blades.

There are specific lubes made that do the same thing, but try the soap trick. You may be pleasantly surprised.

And fully cured, properly mixed resin should dust when hit with a grinder, not gum up the stone or disc. Be sure to wear a respirator when grinding the stuff, too.

Edited June 25, 2016 by Ace-Garageguy

[10thumbs]

I agree with Bill and think carbide burs get better results with aluminum.   Diamonds smear, carbide cuts.  I like the cross hatched burs.  For adjusting things after getting the aluminum close to the size needed, touch things up with a rubber wheel, this makes the cut smooth and shiny.

The same burs work well with resin too.

Just about all of my model work is done with these few.  The fatter bur in the pic is the best one for all metal and resin. About 15k rpm's is a good start.

[Snake45]

Thanks for the advice and ideas, fellas!

Here's what I'm trying to do: I have a number of solid aluminum or solid resin dummy guns (acquired when a local holster maker went out of business) that have the entire trigger guard areas molded solid. I want to lay some model-fu on some of these and turn them into nice-looking wall-hangers for my man-cave.

Two of them are this picture, the solid aluminum Walther PPK and the gray resin P5 (lower right). I suppose the best way to do this would be to drill a series of holes on a drill press, knock out the main chunk, and then clean up with a file (which I'll do in any case), but I don't have access to a drill press.

[1930fordpickup]

An 1\8 in drill should fit an 1\8 collet just fine Snake or just drill with a hand drill. .

 

[Mike_G]

A jeweler's saw is the ticket for that

[Snake45]

A jeweler's saw is the ticket for that

It would be if I could find a strong enough blade. Or several such, as I'd anticipate breaking a number of them in the process.

You know, a coping saw might work fine for the resin ones if I can find a suitable blade. Thanks for the idea!

[High octane]

I need to grind some aluminum, and also some resin (different projects). What type of Dremel grinder bits are best for these? I've had aluminum just pretty much "plate" a grinding stone in a Dremel before, and had resin melt and gum up cutting-type grinders.
 

The FIRST thing you need for this procedure is a pair of "safety glasses," as modern medicine has still not found a way to replace the human eye.

[Snake45]

The FIRST thing you need for this procedure is a pair of "safety glasses," as modern medicine has still not found a way to replace the human eye.

I wear them all the time anyway, side shields and all.

[High octane]

I wear them all the time anyway, side shields and all.

A good man you are for wearing them, as I used to work construction and saw SO many guys not wearing goggles when drilling, sawing, grinding, etc. and they looked like an "accident waiting to happen."

[SfanGoch]

I have a problem finding a pair that fits comfortably.

[Mike_G]

It would be if I could find a strong enough blade. Or several such, as I'd anticipate breaking a number of them in the process.

You know, a coping saw might work fine for the resin ones if I can find a suitable blade. Thanks for the idea!

Jeweler's saw blades are pretty fragile, you just have to go easy, lube them with beeswax and let the blade do the work.