How to get rid of Fine scratches caused by buffing

[deanler]

Hey all. I have a small buisness making billet serpentine pulleys and other accesories for dodge dakotas. I'm having a HELL of a time getting these fine scratches out of the work piece. Im sanding them in the lathe after machining then sanding them by hand quickly in the opposite direction, then i use a black compound on sisal wheel until all the little ridges and nooks and crannys are smooth, switch to a sisal with white compound on it to shine it up a bit. Then i go to a flannel wheel with red, Then finally finish with blue.

The picture is of the small "scratches". They are definatly not left over from the sanding as the scratches follow the way im buffing it

Any suggestions would be GREATLY appreciated, this is driving me nuts



The scratches im talking about are at the 5 o'clock and 12 position

[baz]

my guess would be the sisal , i don t use sisal on aluminium it s too agressive

[deanler]

Thanks for the quick response, I'm almost positive the marks are left from the flannel wheel, It's leaving these marks wherever i buff with it. The part is a complete mirror finish if i look straight at it but at angles it shows these scratches. Is there a finer wheel or compound to use? What process do you use for polishing aluminum?

Thanks alot

[CarWiz]

No use using two compounds on the same buff--You'll get the action of the coarsest polish used on that buff. Also, the red and blue are used for burnishing so you won't get hardly any cutting action out of them, especially the blue. These (blue & red) should be used with a unsewn soft cotton wheel as the final polish. It spins off easily so you need to apply it every few square inches.

The buffs accumulate metal and polish. Screed the buff often--Every 5-10 minutes of use. I would use white compound on your flannel buff. That should polish out the scratches from the sisal wheel and give a pretty good mirror finish on aluminum. Then use a separate buff for the blue, if necessary.

[woodjames]

I get those little scratches all the time. After the blue on the flannel, best bet is to throw it back on the lathe. Finish them with Macguire's(sp?) mag and aluminum polish. It's pink and kind of smells like peppermint. You need to apply it with a microfibre, though I've found charmin toilet paper works as well if not better, but doesn't last long. That'll take care of those marks. I get the polish from advanced auto, but most larger auto places will have it.

-Jimmy.

Originally Posted by deanler

Thanks for the quick response, I'm almost positive the marks are left from the flannel wheel, It's leaving these marks wherever i buff with it. The part is a complete mirror finish if i look straight at it but at angles it shows these scratches. Is there a finer wheel or compound to use? What process do you use for polishing aluminum?

Thanks alot

[stayhi]

i agree if you have a lathe already just get some automotive polish[i prefer mothers] and do a final run by hand. in fact i wouldnt even touch the buffer w/ that piece. just leave it on the lathe up to 1500 grit then polish and it should look great. also any scratches left behind will all be uniform as if theyre machine marks.

[maahi]

Thanks for the information.