MikeM

Your valve covers look like some of the last GM issue to me. Some of the better ones at that.

Plastic Pig

The mold cracked at the "O" not the "T"

Z51JEFF

These valve covers do have the crack impression in both.

John E. DeGregory

Please tell me how you would expect someone to take the pits out of a POC valve cover that is deeply pitted. I mean if it was just a smooth casting that was pitted that is one thing. But a finned Corvette valve cover with the script and all would be downright impossible to refinish to perfection if it is all pitted.
About a year ago a member of a local NCRS chapter gave me his 1960-61 valve covers to refinish. They were pitted big time so I told the owner they were not worth redoing. He said well do them anyhow as he felt sure our refinishing process would make them look nice.
Well it didn't and either would anyone elses operation on the entire planet earth and maybe Mars too.
So please be fair in your comments. Glass beading a pitted part isn't going to do squat.
When I restore fuel injection units the first thing I look at is the aluminum castings. If they pitted or if bubba has screwed them over then you can expect they will not be anything to brag about when the resto is done.
Meanwhile I basically do fuel injection restos and the valve cover is just a little side job.
Recap: The refinishing process does not remove defects. It enhances them. We can sand out minor defects but if you have broken fins, hammer marks from guys beating on them, or other flaws then that's the way they come back.
Now if you wanna pay an hourly rate for my helper to sit down and sand his butt off on them for about a day then the valve cover will be a lot nicer but not perfect. Sandcastings are a piece of cake to improve. They can be broken in half and still comeout nice. But die cast is a different story. If there are others in this world that can make pittted POC die cast parts look good then the solution is quite simple. Let them do it and give me their name as I will send them a lot of business.
Take care, John DeGregory

John E. DeGregory

Please tell me how you would expect someone to take the pits out of a POC valve cover that is deeply pitted. I mean if it was just a smooth casting that was pitted that is one thing. But a finned Corvette valve cover with the script and all would be downright impossible to refinish to perfection if it is all pitted.
About a year ago a member of a local NCRS chapter gave me his 1960-61 valve covers to refinish. They were pitted big time so I told the owner they were not worth redoing. He said well do them anyhow as he felt sure our refinishing process would make them look nice.
Well it didn't and either would anyone elses operation on the entire planet earth and maybe Mars too.
So please be fair in your comments. Glass beading a pitted part isn't going to do squat.
When I restore fuel injection units the first thing I look at is the aluminum castings. If they pitted or if bubba has screwed them over then you can expect they will not be anything to brag about when the resto is done.
Meanwhile I basically do fuel injection restos and the valve cover is just a little side job.
Recap: The refinishing process does not remove defects. It enhances them. We can sand out minor defects but if you have broken fins, hammer marks from guys beating on them, or other flaws then that's the way they come back.
Now if you wanna pay an hourly rate for my helper to sit down and sand his butt off on them for about a day then the valve cover will be a lot nicer but not perfect. Sandcastings are a piece of cake to improve. They can be broken in half and still comeout nice. But die cast is a different story. If there are others in this world that can make pittted POC die cast parts look good then the solution is quite simple. Let them do it and give me their name as I will send them a lot of business.
Take care, John DeGregory
P.S. Their is NO RESKINNING in any of our process. Just refinishing. No material is put back on a valve cover. When a person uses the term reskinning that is dishonest. I never use that term but read it all the time all over the forums.

Ron Miller

Reskinning, refinishing, bead blasting, different processes. I think the guy has asked a legitimate question and isn't knowledgeable about what "reskinning" or refinishing will achieve. He's apparently somewhat familiar with beadblasting, which refinishing is not, but still doesn't know what to expect from a refinishing process. I believe that's why he asked about the pits being filled, which you've said that refinishing doesn't do.


I don't think his question has yet been answered, to be truthful. Just my opinion . . . Are they cleaned and surfaced burnished or "polished" in a vibratory unit, or similar??

Joel 67

Not holding my breath for an answer though.

JohnZ

It's a tumbling process, with each guy's favorite media, and none of the folks who do it are going to give you any more details than that. Deal with it.

Ron Miller

Thanks JohnZ, finally a definitive answer. That or a similar process was what I initially thought. I don't think anybody's looking for any trade secrets nor to go into competition, the guy's just wondering what type of a process the covers undergo.

So Joel 67, I think you've enough information to do a little research on your own at this point. If you'll Google some of the various finishing operations, such as the one I listed in my first post, you'll be a little better able to determine just what is involved.

In any event, I'd recommend talking to someone who has had theirs done satisfactorily, perhaps let the prospective refinisher take a look at your covers before having them done. As JohnZ mentioned, everybody's got their own procedure, and not all will turn out the same.

Cheers,

Fawndeuce

Thanks John. I found this top secret video of the process actually being preformed by highly skilled professionals.
These are just dry, or "calibration" runs. During the actual process the technician would of course be holding a pair of aluminum valve covers, or maybe an intake manifold.
As is common among machinists, Eastern Europeans seem to also be particularly skilled in this trade.



Paul

Ron Miller

Now that's pretty good, explains the process without giving away any secrets!!

Z51JEFF

Alright,its a tumbling process.Ive seen Alt casings done this way and they looked amazing.Whats it cost to have a set of valve covers done,or is that top secret too?

toddalin

Call Automotive Expertise in Huntington Beach, CA and ask Steve LuVisi for a price on having them tumbled. They do turn out a little different than media blasting.

JohnZ

Jerry MacNeish does them for about $100 for a pair.

www.z28camaro.com

Z51JEFF

Thanks for the info guys.