Jeweling metals, need info

[rendoman]

Hi all!

I'm searching info about this technique, I would like to use on the aluminum panel of my next amplifier
I saw some video on youtube about attempts, but there is nothing about a good work.
In local shop there are no tools at all, I saw that there are some rubber rod filled with abrasive, nearly impossibile to find here.
Someone used steel brush, someone rubber with polishing paste.

For a good job, in your opinion, what's should I need?

That's the effect I desire



https://www.customshopinc.com/produc...shingjeweling/

[mklotz]

The rubber rods filled with abrasive you mention probably refers to Cratex products, examples of which are shown here...

https://www.amazon.com/s/ref=nb_sb_s...=1PG71K5J1ET9R

As an alternative to Cratex, I've had some success using sections of wooden dowel with a patch of leather glued on the end. Smeared with lapping paste and rotated in the drill press, they leave a nice circular swirl.

An attractive jeweling job requires two things. First the spacing of the circles must be consistent; spacing errors will stand out and look bad. Arrange some method of mechanically stepping the work between swirls. Don't try to space by eye. Second, the pressure with which the tool is applied to the work should be consistent. While this is slightly less of a concern than the spacing, it's still important.

Be sure to experiment on some scrap before working on the amplifier. Undoing a bad jeweling job is very difficult.

[rendoman]

Thanks for your suggestions!

A question for you: which lapping paste is necessary according to you?

I want to try your method, with wooden dowel plus leather patch, I think a 6-8mm diameter should be fine for 250x120mm plate.
Since my milling machine is tiny, I would have thought of building a sort of plate-template with an accurate grid well spaced (according to size of dowel), with a back stop where it's possible to slide manually. It could be a very long work, but it seems a nice idea, I hope

[mklotz]

I have a kit containing four grades of lapping compound. It's probably forty years old so I doubt it could still be found.

The grit you use depends on what appearance you wish to achieve; it's really an artistic, not engineering, choice. My suggestion is to get the least expensive automotive valve grinding compound you can find locally there in Italy and try it on a piece of scrap material from the part you wish to jewel. That will give you a sample from which to judge whether you want coarser or finer grit.

Such experimenting will also give you a chance to decide what overlap of jeweling circles you will want. Overlapping by half the diameter of the circle is common but, again, it's up to you to decide what you find attractive.

Good luck and be sure to show us some pictures of the finished product.

[mklotz]

Not that it will be much use to you in Italy, but my aforementioned box of four grades of lapping compound came from:

Gerald Kerr Associates
8999 W. Pleasant Valley Road
Cleveland, Ohio 44130

(I Googled them but couldn't find any current listings; they're probably long gone.)

It contained cannisters of grade 120, 220, 280, 500 (order coarsest to finest) grit. I can remember using the 220 and 280 grit on some jeweling jobs.

[rendoman]

Thanks Marv!

I just tried for my curiosity a fast tool with leather, glued with mastic.
I tried to put some White polishing paste crumbled and amalgamated in oil, I know it's a bad job, but it was just an attempt to see what would happen. I used 3000rpm with light pressure, the signs are visible after cleaning, but I bet I need something more aggressive. The aluminum scrap was only cleaned with 180 grit paper, too rough maybe for the job

[mklotz]

It looks like what we call "white diamond" polishing material here in the USA. A bit too fine for jeweling though, as you've proved, it produces the characteristic swirls. Do try to get some lapping grease in the 100-200 grit range.

At any rate, you seem to have proved the leather-on-dowel tool works reasonably well. Keep up the experimenting; you'll soon be an expert.

[bruce.desertrat]

Grinding and Polishing grits of a variety of sizes are generally available through lapidary and jewelry supply places.

[desbromilow]

Hi,

in the past I've done this with a piece of dowel (wooden) and common valve paste. The suggestion of using a piece of leather glued on is better than how I did it, since I had to renew the valve paste a few times per row.

I've seen it done with those old school "ink erasers" - the guy used a small section of brass tubing as a die, and cut several pieces from the ink eraser, and then let them feed out of the same brass tube section as pads. They didn't wear too quick, and all he did was push a bit more out as it wore down. I think from memory he had a nut and piece of all thread soldered at the end of the tube for feeding the eraser nubs back out.

Des

Hi all!

I'm searching info about this technique, I would like to use on the aluminum panel of my next amplifier
I saw some video on youtube about attempts, but there is nothing about a good work.
In local shop there are no tools at all, I saw that there are some rubber rod filled with abrasive, nearly impossibile to find here.
Someone used steel brush, someone rubber with polishing paste.

For a good job, in your opinion, what's should I need?

That's the effect I desire



https://www.customshopinc.com/produc...shingjeweling/

[blkadder]

I have used regular metal polish doing small parts, and they turned out pretty well. I did try using regular pencil erasers, but they did not last very long at all.