i have recently picked up an old set of cal custom valve covers for the FE in my 57 wagon . unfortunatly they have been sitting for quite a while and have dulled and oxidized . i am looking for advice on bringing the shine back .
Polishing aluminum can be a pain if you dont have right tools. There is a guy here that does a nice job inspite of being an assshole. I think he goes by aqtw31 , his name is Andy
Depending on how bad the finish is I like to wet sand them before polishing. 600, 1200 and then 2000 grit paper. You can vary or skip grits depending on the condition of the covers. After this I buff on a wheel with 3 different compounds, but Mothers, Flitz or Semi-Chrome polish and an old towel with elbow grease will work well too, just takes a few beers longer No need to send them out for polishing. You can get great results at home. Save the money for more parts. Good luck.
Just saw your pics. I wouldn't media blast. You'll just have a coarser finish to smooth out to get a high polish. I'd stick with the wet sanding. Just my opinion. Others may have good results with blasting.
I don't know why people don't check the archives,,maybe it's because they don't know it exist, check this out. HRP http://www.jalopyjournal.com/forum/showthread.php?t=97179&highlight=polishing+aluminum
On the media, if you had a blasting cabinet with worn out sand, then it might clean up those fin recesses easier than sanding. If you don't have blasting, then do it like rockfish said. You could even try different grades of steel wool before buffing if you don't have a bunch of sand paper grit numbers. A little bit of dull looks good between the fins, if you shine the tops of the fins real good. One tedious spot will be those recesses where the bolts go. Might need a mini buffing ball on a drill.
I use heavy grade liquid polishing compound and a wool pad on a body grinder. It worked good on my big truck shiny wheels and here's a b4 and after pic of mine that i did,,, still could use a little more work. You can also use a cotton polishig wheel and hard stick compunds if you have an arbor to put it on. They make about 4 grades from jewelers rouge to black emory. Be ready to get dirty!!
I haven't tried this product, but it got rave reviews on another car forum I frequent. http://www.californiacustom.com/purple_metal_polish.html I think they used the deoxidizer and the polish from that site. I believe you can call and get a sample too. These pics are from a guy on the other forum...not the seller. Old aluminum tube After a 1 min spot treatment with deoxidizer shows a clean oxide free area After 30 sec application and buff off the residual polish
Hi, well I am a veteran polisher with 25+ years experience and I am not an "ass-hole" as someone else is described as .........All the hints and tips here thus far are good, you can do this yourself without specialized equipment it just takes time, when you do it for a living time is $$. I use a higher speed polisher and larger diameter buffing/polishing wheels than most would at home and a 10hp lrg scale polisher. Media blasting is OK, I would say glass so as not to make to coarse of marks in the finish, just like you wouldn't want to start with too coarse of sanding grit 'cause you have to work those scratches out and aluminum is soft. Just my thoughts, I could polish 'em for ya, for $ or I trade as well, here a picture of my Buick covers and my beast of a machine.......
Only problem here is the comparison of a aluminum extrusion (a very high grade and purer aluminum quality) than any cast valve cover is. extrusion polishing is like polishing billet aluminum 6061 or 5052, very easy to polish compared to an inferior aluminum quality thats in most cast items, along with better results as well....
I've got a buffing wheel mounted on an old washing machine motor that I buff valve covers with, along with a couple different types of buffing rouge. I've found that die cast covers (like Cal Customs) don't tend to polish up as nicely as sand cast covers (like Edmunds, Offenhauser, and the original Edelbrocks).
I used three grades of WENOL products (Red, Blue and Pink Tubes) to polish the aluminum, chrome and stainless parts pictured: