Advice needed

[Evan]

I am working on a project that I would like to dress up a bit. I have never done jeweling on aluminum (also known incorrectly as engine turning). I want to apply this finish to aluminum and have tried several different approaches. I tried a hardwood dowel with fine abrasive. I tried a pencil eraser. I tried a turned teflon dowel with fine abrasive embedded in it. None of these approaches worked satisfactorily.

The aluminum is soft and picks up the slightest extra piece of grit and leaves a nasty mark in the pattern.

Ideas?

[3jaw]

Two things come to mind. One is to try a small wire brush (the size you would use in a Dremel). The second comes from Brownell's gunsmithing supply. They sell small abrasive brushes that are used to jewel rifle bolts. Usual disclaimers.

Hope this helps.

Greg

[winchman]

How about a round metal brush such as the McMaster-Carr item # 7273T22 on page 2505.
http://www.mcmaster.com/

You could cut the handle off, and chuck the round piece which holds the stainless steel wire bristles.

If that's too stiff, you might try something like the 3/8" diameter pencil style brush with 0.003" brass bristles, item # 7248T17 on page 2504.

I'm thinkng the brush would be less likely to trap a piece which would gouge the aluminum you're working on.

Roger

Drat--I hate it when I forget to check back before hitting the submit button.

[This message has been edited by winchman (edited 01-03-2004).]

[Ian B]

Evan,

I seem to remember reading that using a small disc of hard felt works well, probably glued to a stiff backing plate.

An alternative might be one of the round sticks of bundles of glass fibres, used for polishing aluminium.

Ian

[ibewgypsie]

On the studebaker dash I built. I rolled a roll of emery cloth or sandpaper around a nail, rolled very tightly. (not too long or it will fold, just 1" or so out of chuck) Pulled the nail out, Chucked it tightly in the drill press chuck. Sanded with the end of the roll.

I took a long ruler and made a 1/2" crosshatch and applied the running sandpaper roll to each cross hairs.

Problem is, was, it holds grit, and if you stay in one place too long it burns a color. Aluminum is much harder to do then stainless. MY custom harley dash was so bright it hurt to ride it in the sunlight.

I have saw very large damascene made with a buffer and rouge. it had a 4 inch wheel. He did a cresent type damascene instead of the round Jeweling I am accustomed to.

I powdercoated the dash clear. The old guy who ended up with the truck has redone it again. I saw it at a show recently.

tooth paste/rouge and wooden dowels work but is slow. If all else fails use Eastwoods kit.

David

[This message has been edited by ibewgypsie (edited 01-03-2004).]

[cem]

The old style abrasive type pencil eraser will do a good job. The key is in the way you apply it to the workpiece. Do not allow contact for more than a split second for each mark. A manual drill press works good as you can just bump the workpiece with the abrasive. With just a little practice you can achieve a great finish. Be sure to set up a method for accurate indexing to achieve a uniform pattern.
Many tool supply houses sell abrasive sticks which work really well. Just pick the correct grit. I would suggest an 80 grit for aluminum.

[jr45acp]

Evan, would a Cratex cylindrical point work? Seems as though it Would. I've messed around with damascening (sp?) using cratex with fair results.

------------------
John B

[G.A. Ewen]

Evan, if you try the Cratex rubberized abrasives let us know how they work. (page 569 in the KBC tools catalogue)

[G.A. Ewen]

I just reviewed the artical "Engine Turning Made Easy" by Bob Marchese in "Metalworking" book one. The author recommends Cratex brown (medium grit) for "materials ranging in hardness from polished aluminum to chrome plated steel".

[torker]

Evan..I was going to send you a Brownells jeweling brush (one of the few things I kept when I sold my gunsmith biz) but can't find the darn things. I just got some of those little wire brushes for a die grinder. They spread out so I wrapped zip ties around it to stop that and it did work but tears the alu even with valve grinding compound. The Brownell brushes are really fine SS wire and would work. I got looking around for something finer and low and behold...#2 welding cable. Cut a 2" piece off, squared up the end, chucked it up, put on a bead of 3M polishing compound and it turned out pretty darn good considering it took all of a couple minutes. I only did about 20 overlaps so don't know how it'd work long term. If you spent the time to crimp some kind of ferrule (sp) around it it'd probably last pretty good. I just put it in the way it was. I have some of those rubber abrasive sticks. I'll try them later and let you know. Damn... that ugly north wind just blew in... w/ wind chill it's -34 an hour ago it was -14.

[torker]

Evan... yes... the rubber abrasive sticks work (really well actually) The ones I have are dark green, 1/2" dia, 4" long. Bought them nearly thirty yrs ago either from Brownells or Price and Markle... I can't remember. To be honest though I like the looks of the welding cable jewels nearly as well but it is more fooling around with the polishing compound etc. Cem is right... there is a knack to it. Sort of a rythym to get them all the same. When I first started doing rifle bolts I'd use a brush for every bolt. After a lot of practice I think the same brush did half a dozen.

[Evan]

Thanks for the ideas,

George, Torker,

I think I will order some of those abrasive rubber sticks from KBC and try that. For now I will settle on a mirror finish

Good opportunity to order some more tools...

[This message has been edited by Evan (edited 01-03-2004).]

[Stepside]

I made some arbors and glued a disc of leather in the end. The counterbore was 1 inch diameter and 1/2 the leather thickness in depth. The leather was a piece of horse harness, so it was quite thick.
Used a mixture of Clover brand abrasive left over from lapping some valves and 10weight oil. Makes a mess but the results were worth it. Used gridded paper for the offsets. Next time it will be water soluble abrasive. Put a weight on the drill press handle so the force is uniform and try to keep the time constant.

[Evan]

I don't have a problem with the indexing as I am doing this in the milling attachment on my lathe. I tried some valve grinding abrasive and it sucked. Maybe I am too picky but it just didn't look good enough.

[Thrud]

Evan

I buy Craytex from the local rock shop for a hell of a lot less tha kBC sells te same stuff for. they are called "Bedrock Supplies" here in Edmonton. They have moved to just the east side of Ackhurst Machinery on Argyll road. Don't tell the bastards they are cheaper than KBC what ever you do...