Noob metal polishing question (steel compound on brass)?

[sploo]

For some time I've been using the Veritas green Honing Compound (Aluminium oxide I believe) for stopping plane irons, and occasional polishing of brass, but I've just ordered my first set of "proper" polishing wheels (sisal, colour stich etc), along with a variety of compounds.

As you're not really supposed to mix compounds on one wheel, is it acceptable to use compounds for steel on metals such as brass? I'll get a black, green and white for steel (first cut and flattening, final polish, and high polish respectively). Mostly with brass I'd just be removing tarnishing and getting a shine (no requirement for scratch removal). Would I get away with the green compound on brass? Should I stick to the white? What's the main difference between the compounds sold for steel and the compounds intended for softer metals?

 

[marcros]

depending on what is in the compounds that you bought, http://www.thepolishingshop.co.uk/acata ... ounds.html suggests that both green and white are ok for all metals.

 

[sploo]

It's Pro-Max brand compound. I understand the compounds for steel can scratch brass as they're quite hard. I guess I could start with some non-critical brass component and try. The kit contains both ferrous and non-ferrous compounds, but it only occurred to me after ordering that there's only one set of wheels (not that it's particularly expensive to buy more).

 

[Rorschach]

Test it and find out on a scrap. Make sure that when you move from wheel to wheel you clean the workpiece inbetween.

 

[sploo]

Test it and find out on a scrap. Make sure that when you move from wheel to wheel you clean the workpiece inbetween.

Good point. I do wipe a plane iron between grits on diamond plates when sharpening, but I hadn't thought about doing that when moving between wheels.

 

[Rorschach]

If you get coarse grit stuck in a fine wheel you may never get it out and it will ruin the wheel. It depends also on the type of compound you are using. Very waxy compounds are worse for this and ones that use very hard grits.
I like menzerna compounds as they produce very hard low wax compounds that don't build up on the wheels and the abrasives are very friable and break down quickly so I just move along my line of wheels with no trouble and no need for cleaning. This is polishing plastics and wood though rather than metal.