How to restore the machined finish in your breather lid...

[85_SS_302_Coupe]

Well, i had this idea for the longest time...i'm sure someone has thought of it or maybe done it but i haven't seen it, and i'm thrilled with the results so i have to share.

You need:

1) a brushed/machined finish breather lid
2) a bolt that just barely fits through the hole, along with 2 washers and a nut to thread onto the bolt
3) a drill press
4) various sandpapers, wire brushes, brillo pads etc for repairing the finish
5) a new decal (which i don't have yet)


Take the bolt and run it up through the BOTTOM of the breather lid, with a washer on first. Then drop the other washer on and tighten the nut down on it TIGHT so it doesn't spin. Next chuck the bolt up into your drill press TIGHTLY. You don't want this thing whipping off like a frisby. At this point you're gonna want to set the drill press to the slowest speed and see how well you have it centered. Also it's common for the breather to be a little bent so you may have to tweak it so that it spins nice and evenly and doesn't wobble. You should end up with something like this (i've already started the process):




Now, you don't need to go super fast with this....in fact it's probably very dangerous. I kept it around 45-50rpm. I started out with 80 grit sandpaper because my lid was very rough and had a lot of deep water stains. It had been glass bead blasted so all the original brushed surface was long gone. If you're just restoring/refinishing yours, you'll want to start with something much finer than 80 grit, but you probably don't want to go any lower than 100-150 or you're gonna start polishing it rather than putting the finish back into it. I found that after going over the whole thing with 80 grit so that all or most of the spots were gone, i went back over it with a stiff wire brush (preferably one that's not all bent and bristled up because that'll cause irregular brush marks) and worked my way around it with that, and then went to a heavy brillo pad that's used for prepping head surfaces. Then as a final touch i went over it with a softer bristle brush to really fine out the brush marks.

Here's what i started with...this is the surface after being glass bead blasted. It's not a good pic, but suffice to say it looks like a satin metallic silver paint job...it had a super fine grit finish to it. I liked it, but wanted it to look original.



Here's what i ended up with:





A couple drawbacks....1, your lid is now raw aluminum. You have a couple options here....either spend a fortune for aluminum sealer (Zoop is a good product for this but it's espensive), or try your hand at a spray clear coat, or have it powder coated clear like i plan to do. Another thing is, it shows every ding and imperfection in the metal, which mine clearly has plenty of, but hey it's 25 years old and has lived a rough life. Third, DO NOT TOUCH IT before you clear it or something, or the oil from your skin will stain the raw aluminum. I'm keeping mine in a plastic bag until i can get it powder coated. Once it's coated, i'll install the decal. The pictures make the blemishes look worse than they really are....once it's on the car it'll look fantastic, and like i said if you have a nice lid that just needs some of the brush marks "fixed", this is the ticket.

Hope this helps someone I've tried this with a hand held drill....don't. It hurts lol

[tbirdman]

Excellent article. I plan on doing this soon, and this is a big help.

[85_SS_302_Coupe]

Another way to do this is maybe with a bench grinder if you can figure out a way to mount it. You might be able to stick a hand held drill in a vice and do that but do so at your own risk. Even with the drill press it was really wobbly. It helps if you have a good heavy leather glove to ride under the bottom side while you press down on the top...it's really easy to bend the lid and cause it to wobble.

The only other down side to this is that you're thinning the lid out some since you're sanding some off...so i wouldn't make a habit out of this.

[bkoons85gt]

Great Tip, Thanks for posting.

[escogt]

Nice job & nice posts. Thanks for sharing that cool info.

[85_SS_302_Coupe]

NP guys, glad to help. I have 2 more lids, one of them is actually very nice but has also been bead blasted...it doesn't appear to have any dings in it so i'm gonna do that one too and try to see how nice i can get it.

I've actually never seen one in mint condition in person....if anyone cares to post a pic up close of one that's really nice, i'll see how well i can mimic the finish and then post back on what grit paper etc i used to get it there.

[sowaxeman]

Does the pressure you are applying with the sandpaper and brushes cause a potential problem with bending the lid downward as it spins? Might it be better to use some sort of roller/ball thingy on the underside to apply counter-pressure as you work...especially out toward the edge?

This is a great idea...I have the lid from my old '85 Vert that is in mediocre condition. Might just have to try this on it.

[85_SS_302_Coupe]

It does which is why i was saying it helps if you have a heavy leather glove so you can ride your hand under the bottom. You don't really need to apply heavy pressure..just let the paper do the work for you, but it will eventually bend a little so you need to be careful. Now that you mention it if i had a chair caster or something like that i could've made something to ride underneath it...as long as it didn't press too hard and make a groove.