How Do I remove tiny, light scratches from Aluminum?

[chem_man3]

I am currently polishing the lower part of my 1982 Suzuki GS850 motorcycle engine. I have progressed through all the necessary steps in order to achieve a mirror like finish on my aluminum.
The problem that I am having is that I cannot get rid of the light scrathes. I have a great finish, but it is not smooth and scratch free.
I started with Tripoli rogue on a spiral sewn buff the went to White rogue with a loose section buff. Ihave followed this up with a Jewelers rogue on a Canton soft buff hoping to get rid off all the scratches.
I have gotten rid of most of the scratches but I have the scratches from the Jewelers buff.
I am using 4" buffs on a motor that turns 1500rpm. I am applying medium to light pressure and using a criss-cross pattern to polish my pieces.
PLEASE HELP ME TO GET RID OF THE LIGHT SCRATCHES IN ORDER TO ACHIEVE A SMOOTH MIRROR FINISH!
I am so frustrated.
Thank you for your help.

[marsfrogie]

Are the scratches even, or are they relatively random? If it is random, you most likely have dirt or metal particles entrapped in your buff.

[chem_man3]

The scratches are even as far as depth is concerned and appear in the direction that I buff. I do rake the buff before applying more compound.
Thanks

[blip01]

I started polishing with 4" buffs on a drill that turned 2800rpm and did not get great results, plus it took forever to get the results. I recently tried some 6" buffs on the 3500rpm bench grinder where I work and all I can say is the difference was very noticeable . Even just getting the buff heated up to a good temp. and gettting the compound on the buff was a pain with the 4" ones, spinning the 6in. ones at 3500rpm generates plenty of heat to get the part and the buff nice and hot. I barely need to touch the compound for a split sec. to reapply it to the buff now. I'm no expert, I've just recently started to polish parts on my bike, but it definitely seems like faster is better. I've gotten really good results with just going up to the black compound so far on the 6in. buffs, I'm waiting for the rest of my new 6in. buffs to arrive before I can try the brown and white.

Check out ebay, you can pick up a super cheap bench grinder that'll spin way faster than your drill. At least step up to the 6in. buffs on your drill, trying to get the casting marks out of my rocker box covers, and aluminum wheels was taking forever with the 4in. ones.

Good luck,

Brian

[chem_man3]

Thanks blip01. I have stumbled across a 1/2hp, 3500rpm, 6" bench grinder. I am finding that it cuts my polishing time in half! Especially when i am using it to smooth out my aluminum with 320 grit grease.

I have polished all of my pieces with brown and from 2 feet away they look perfect. It is when I look at them closely and angle them just right in the light that I can see all the superficial scratches. I tried going to white on a 6" loose wheel, but the scratches remain.
Is it possible to get rid of these scratches completely no matter how it is viewed in the light? If so please help.

This is keeping me from putting my bike back together so that I can start riding. I am hoping to have my bike ready for 2003 Daytona Bike Week and these aluminum parts are slowing my progress.
Thanks!
MM

[blip01]

Yep, those scratches are evil alright! Seems like almost everyone on this board has the same issue with aluminum, those final super fine scratches that just don't seem to go away. Sorry I don't have any secret for you. Like I said I'm very new to polishing and I get great "2ft." results also, looks like chrome, but when you look at in in the bright light up close those super fine hazy scratches are there. Look around for the posts on wetting the part, dusting with talcum powder and buffing with a clean wheel. This technique is supposed to help but I tried and didn't really see any difference. I am getting better results than when I first tried, so practice does help. I now use an 8 in. loose cotton wheel on a grinder and do several passes on the piece in a criss-cross pattern. This seems to get the scratches almost to an acceptable level, for me anyway. Keep raking the buffs too! That definitely helps. Good Luck, and whoever has the secret to getting rid of these damn scratches better come clean soon!

[chem_man3]

Blip,
I went to a 6" loose and used a red (jeweler's rogue) on my bench grinder. Using the afore mentioned criss-cross pattern, I was able to get rid of almost all of the scratches. It took sevral passes, but I finally got what I was looking for.

I am not sure if it is the rogue that I am using but now I have a haze on my aluminum. I cleaned the metal with acetone, but to no avail. I know it is not the metal because the haze was not there when I was polishing with brown. I have ordered some FLITZ polish hoping to solve this problem.

This polishing process (criss-cross) seems to work great on flat or rounded surfaces but the more advanced parts (like triple trees) cannot benefit from this process because of their shape and size. I tried a dremel, but had no success. I may have to live with the "2ft look" on this part.

I also tried the talcum powder, but i did not have any luck.
I agree. Stop hoarding all the SECRETS. We need to work together for a BRIGHT and SHINY future!
Thanks for you help.
MM

[blip01]

Great! I just picked up some red rouge today too and hope that will get me that little bit farther I need to be happy. I also found a decent book on polishing aluminum http://www.powells.com/cgi-bin/bibli...1-0972461809-0 It covers all the basics, great for begginers. No huge secrets revealed but it's extremely thorough about the whole process. The most important thing I took away from it was keeping parts SUPER clean bewteen each buffing step and avoiding ANY cross contamination of compounds. I am going to try a way more thorough approach to cleaning parts, hands, etc. between each step and see if my results are better. Well worth the $11 bucks for the book if you're just starting out.

I too have my bike in pieces and need to get crackin'. Good luck.

[rgsx907]

What kind of light are you under I have found that fluorescent lighting shows fine scratches , but if you take it under sun light they are gone .

[mcaswell]

You might want to save yourself the $11 and read our free buffing booklet at http://www.caswellplating.com/buffs/buffman.htm

It covers all the basics of polishing any metal.