Getting a perfect mirror finish

[mole New User Find all posts View Profile Close mole]

When polishing aluminum is it possible to get a mirror shine finish? or when you look at the piece your doing up close, is their always going to be impefections, like hairline scratches.

I've been working on some atv rims and they look great from a foot away but if I get close to them I see alot of imperfections.

Is their anything I can do to make them perfect, or should I just be happy with what my results are now?

BTW i've been sanding them first, then using a sisal wheel with black, then spiral with brown, then loose with white. (With white what works better the liquid or the bar compound?). I use a 3/4 horse grinder that has 3 amps for the large areas and a die grinder for the real tight areas.

Any suggestions would be great

[bhhodges Amateur Metal Finisher Find all posts View Profile Close bhhodges]

your material list sounds ok to me. my question is--- you say i sand first-

what is your sanding steps


bill

[mole New User Find all posts View Profile Close mole]

I first use greaseless compounds 80,120,180,240, then I wet sand with 400 and finally 600. It comes out nice and smooth but my problem is when I'm done polishing. Its nice and shiny but their are hairline scratches. can you think of anything im doing wrong in my polishing process.

[bhhodges Amateur Metal Finisher Find all posts View Profile Close bhhodges]

you use a different wheels for each greaseless compound and clean item inbetween each step??


bill

[Guest Close customandsound]

for greaseless use a spiral.. cotton .. i use a 4" with all my greaseless

[skiddz Experienced Metal Finisher Find all posts View Profile Close skiddz]

The battle of the scratches.. The more stuff I polish, the more I'm coming around to tomg's train of thought in regards to heat being your friend. When I'm going to town with the sisal wheel and the black compound, it seems the hotter I can get the part through friction, the better my end results are. When I start feeling heat through my Nomex gloves, I know I'm pushing hard enough. I also hit the wheel with compound for about 1 second every minute or so. Seems to "renew" at just the right rate for me to keep making progress.

I've also been crossing my directions with the initial buff. Do the entire part one direction, then turn it 60-90 degrees and go over it again. I did two brake levers over the weekend that were beat up like you wouldn't believe. They both came out fantastic even though I had to start with 120grit greaseless to get the chips, nicks and pits smoothed out.

I'm really starting to like the black compound on a sisal wheel with an ample amount of elbow grease.

[bhhodges Amateur Metal Finisher Find all posts View Profile Close bhhodges]

no amout of reading will overcome what you just said, trying ideas on your own. some polishers will even use a small propane torch to help heat up some items while they are polising them.


bill

[mole New User Find all posts View Profile Close mole]

Like u said Bhodges, last night i tried something different. I had a feeling maybe I wasn't cutting deep enough into the metal so I decided after a good pass with a sisal and black I switched to a spiral and black. The almost perfect shine came through no scratches pits or anything. After both of those passes I hit it with white and now you can read the newspaper by it. Amazing results by just changing the wheel i was using.

I will post pictures as soon as I get ahold of a camera. I'll post before and after pics because anybody that knows the 97 banshee knows how godawful the gold rims are.

[skiddz Experienced Metal Finisher Find all posts View Profile Close skiddz]

I know exactly what you're talking about mole. Add 10 years to the age of your Banshee and you've got mine. I'm a little over halfway done with the rebuild and there's not a single aluminum part on it that hasn't gone under the buffer. Still struggling with the carb bodies, but those are like trying to polish the nooks and crannies of an english muffin...

All in all, it's been a great learning experience. I think I've got a handle on what I need to do to get excellent results now as my last 4 pieces have come out extremely nice. Check out the pic I just posted in the "got a new toy" thread.

How'd you get the gold anodizing off the rims? Chemically or with sanding/buffing compounds I've got a set of rears I'd like to revamp...

[mole New User Find all posts View Profile Close mole]

The first thing I did was take the tires off (im getting new ones) and the valvestem makes things alot easier. Next I took my heat gun to the rims and made them just hot enough that I could feel the heat through my gloves. (I read a bunch of different sites before I did this and most of them said it works best when the metal is hot). Anyways then I just sprayed on the oven cleaner. Spray it on thick and let it sit for a few minutes and then see if anything is happening, when you see it starting to come off spray more on and as it thickens it will start falling off. Have a good area for this cause its messy. Then if all of it doesn't come off by the spray then take a sponge and start wipping it down. BTW only 2 of the 4 rims came completly clean of the anodizing. But don't worry only a little bit is left on the rim.

What I did after all that was took some greaseless compounds to it from 80 grit through 240 and the rims were compeletly clean and ready for a little bit more sanding. After the greaseless I sanded very little with 400 wet then 600 wet. It left the rims almost polished. Then u just polish them.

Its a slow process but mine don't need to be ready till the end of march when I goto Pismo.

The only problem im having is with the center of the rims they r a pain in the rear to get to. I even have a flex shaft but cant seem to find the perfect bob to use, that and the centers seem to be really pitted compared to the rest of the rim.

If you have any advice on what u would do for the centers let me know.

[skiddz Experienced Metal Finisher Find all posts View Profile Close skiddz]

I have used a tapered buff (http://www.caswellplating.com/buffs/tapered.html) chucked up in a drill in the past. I did just get a couple mushroom buffs I'm gonna try on my wheels to freshen 'em up. I'll probably use the flex shaft so I've got a bit more "mobility"

[mole New User Find all posts View Profile Close mole]

Im thinking of trying that stuff you spread on then roll in the compound for some bobs. I really hate to sit there and sand by hand all day. Some of the spots I work on are really tight, need something small to get in those areas.