hey guys I have a question regarding paying someone to polish a raw cast aluminum valve vs me trying to do it myself. The engine is a 292 straight six chevy with the stock valve cover on it. There is a little tab that is welded to the side of it that holds the throttle valve cable in place that the guys who did the finishing touches for me did. There is a company that makes a really nice cast aluminum valve that you can get raw or polished. I was gonna try and have my uncle who is a welder tack a new bracket onto the new raw cover. my debate is wether i should try and shine it up myself or just have someone else do the polishing.
You could polish it yourself but unless your time is worth nothing you might as well buy the polished version. It might be better to bolt or rivet the bracket on. Easier too.
Polishing with the bracket in place will be more difficult. Buy the polished one, and spot polish the bracket after welding.
if you have large polishing wheels/motor, and experience using it go for it - otherwise get a polished one
Ask yourself if you have more time or money. Polishing is easy but time-consuming. Here's a tech thread I did a few years ago: https://www.jalopyjournal.com/forum/threads/polishing-polishing-finned-al-valve-covers.97179/
I have done that several times and it depends how rough the casting is . If it's rough you will need to wet sand it with probably 3 diff grits , then buff it with 2 diff (orange and white) compounds then hand finish with a good metal polish to get it looking nice. VERY labor intensive and messy. I have an old washing machine motor with a buffing wheel I use. Yea , I'm cheap.
No one is mentioning this but your going to make a black mess all over you too. You need a free standing polisher too with at least 2 different pads.. I touch up already polished parts with a pad on a drill press.
When I first built the sprint car in my avatar, I polished all the aluminum radius rod plus the front and rear bumper. Like Jimmy Six said, be prepared for a black mess. That was enough for me, I had a local polishing company do my last valve covers.
I did these by hand, no polishing wheels or machines, just takes a bit of time, sandpaper and polishing compound like Wenol
I polished an intake manifold for a SBC once. Did a lot of sanding by hand and with a die grinder (cartridge rolls) then moved to a polishing wheel thingy mounted to a 1/2" drill. I clamped the 1/2 drill into a bench mounted vice in my basement. Was a lot of work and tons of sanding. It looked amazing ... until I took it outside in the natural light ... whoops, time for more sanding as I could now see a lot of scratches. When I was finally done, I was very happy with the look as it matched the polished rocker covers and air filter. I practiced on an alternator case before I attempted the intake. In my opinion, a valve cover would be quite easy. As for me, I have tired of the "show" look and simply grind/cartridge roll all numbers/names off aluminum parts then sandblast and install them. If I wanted something polished, I would not hesitate to do it again though. It shouldn't be hard to find some of those spiral wound polishing wheel things and a selection of compound sticks. I would never pay someone to polish aluminum, it really isn't hard to do, just very time consuming.