squealingtires

iTrader: (14)

I've got some TT2's and it seems like I cant get a very good polish out of the center "spoked" section. Upon closer inspection of the surface it has a "porus" look to it. Will I ever make it through this by polishing/sanding ect or is it like a granite coutertop where it will never be completly smooth? Is this just what happens during the casting process?

~JOSHUA

iTrader: (92)

All polished parts must be sanded perfectly smooth to get good results.

That's why my polish work is near chrome. It's sanded close to 1,200+ grit before buffing on heavy buffers that take care of the rest with tripoli.

All the buffing in the world won't cure a pourous surface, it must be sanded glass smooth for best results.

squealingtires

iTrader: (14)

Not porus like a sponge but looking at it very close the metal is like an orange peel. I took 320 grit paper and sanded a small section for about 3 minutes altering direction by 90 degrees every so often. Then I followed with sand paper at 600 grit, 800 grit, 1000grit, and finally 1500 grit emery cloth. Then I buffed with the black compound for a while on a spiral sown buff then changed buff wheels and used tripoli compond and then finished with a loose buff using white lightning compound. Again, examining the surface it still had that orange peel look.

Is this a common sympton of a "cast" wheel as opposed to a rotary forged wheel?

squealingtires

iTrader: (14)

back to the top for my last post because I'm not making any progress. I can't get the center section of the TT2's to gleam like the outer rim. The outer rim has a deep shine while the center section is just shiny but not nearly as shiny as the outer rim.

Is this some phenomena of cast alloy wheels? I need some pics to show you but it seems like no matter how much I sand and buff the surface stays the same. That is why I used the granite countertop example. Anybody else had experience with this?

squealingtires

iTrader: (14)

ttt for this evening. Thanks

squealingtires

iTrader: (14)

Well, I finally got back to the wheel polishing. It is my understading from a Material Science perspective that the grain size of a cast wheel will be much larger than that of a forged wheel. Cast wheels solidify like ice glass where forging a wheel "mixes" the grains together to form a much more uniform surface finish. Is there way to produce this forged like finish on a cast wheel? Since aluminum is somewhat soft would bead blasting or microniting mix the grains up on the surface much?

VegaJim

iTrader: (1)

You will never get a cast aluminum part to shine like a billet or forged piece. The cast part will always be porous, even when sanded smooth. Alot of it depends on the quality of the ingots they used when the part was cast. Hand polishing cast pieces will never give you the same results as machine polishing. I'm not talking about talking about buffing with a dremel or a drill with hardware store buffs and compounds, I'm talking about using real machines that usually aren't readily available to the average auto enthusiast. I have been in the metal finishing business for 27 years, here is one of the machines I use, I am actually polishing a stainless crossover pipe for a turbo set-up. Machine is a 15hp variable speed unit with a 16 inch buffing wheel. Here is also a crappy picture of a 88mm large frame turbo. I also have a semi-automatic wheel polishing machine, but I don't have any pictures of it.

Phoenix 5.7

iTrader: (7)

the spokes on my TT2s frustrate me too. can get the barrel shiny as all hell, but the spokes only get mediocre.