64 chassis restoration

[Greg H.]

Hi all, a couple of things to bring up after a long hiatus.

I was looking through some old threads and saw the factory pictures of the 63 with the fully painted rear end assembly going onto the frame. My judging guide states natural finish for the half shafts and differential. The post was from 2009 and I have only had the manual for a year. So what is the latest consensus on these parts? I prefer to keep them rust free with black paint, but was planning to go with natural finish (maybe some clear or something to hold off rust).

I'm still at the point where I am struggling to clean up the frame, make weld repairs, and get the proper coating to preserve the bare frame, so I am looking for advice on keeping the rust fully at bay. My first attempt is showing signs of failure. The sandblast left some specks of rust deep in the pitting which I attempted to cover with self etching primer from SEM. It has bled through as I've spent a few months making repairs to the frame. I'll add a picture after I save my post. So now I am looking at re-blasting but not sure if I should just spot treat those trouble spots. Seems like the clean areas are ok after a summer of humidity. Next step was to be epoxy primer (Deltron DPLF). Then chassis black top coat. But SEM is telling me now I should not have used their self etch, it would be better to go straight to epoxy primer.

It seems like there are many different approaches taken (powder coat, POR15, epoxy primer... ) so is there a consensus from NCRS what is the best practice?

Any advice is greatly appreciated!

[Bob R.]

Re: 64 chassis restoration

The old judging guide called for the rear suspension to be painted black and when I did my car I went by that information. The new judging guide calls for no finish on the suspension. Many of the regulars on this board that have owned there cars since new say black is correct so there is no clear answer. I did not get penalized at recent judging for the black finish and I would prefer it painted so no rust issues I'm keeping it black. Originally the factory used an asphalt based black material on the frame and after a few years most of it came off. I cleaned my frame removing as much rust and corrosion as possible and sprayed it with black satin paint.

[Joe R.]

Re: 64 chassis restoration

The 63-64 Judging Manual is wrong on both statements but that another subject never to be discussed on this forum!!!!

As I have said before, imagine a frame coming down the assembly line just before the body drop. The blackout procedure was done with the frame upright- not upside down.
The blackout worker was told to black out everything that does not have paint. He sprayed the suspension from above and the half shafts were blacked out on one side with runs around them.
This has been confirmed by many 63's and 64's that have never been restored before.
So the judging manual is correct half the time!!!!!!

JR

[Gene M.]

Re: 64 chassis restoration

Greg,
I suggest the rust in your photo was there before you applied the finish. The pores in the metal are from the rust. Sand blasting is typical for rust removal. But one must take extra pass with a fine enough sand such as glass bead to insure the pits are devoid of tiny corrosion. A epoxy prime, followed by urethane will give insurance, keeping moisture from re-attacking the metal.

I suggest you "smooth out the metal" so pits are not visible. CDCIF judging will yield deducts for surface deterioration.

I also suggest to you the original coating was not very durable. Any new tech coatings should offer far better protection but may suffer deductions on flight judging attempts. Most restorations in this area are not restored, but refurbished or rebuilt to suit owners taste. In fact it has become so common place to make it better than original that deductions are rare for doing so. This can be said for most areas for almost all "restored" Corvettes.

[Greg H.]

Re: 64 chassis restoration

Greg,
I suggest the rust in your photo was there before you applied the finish. The pores in the metal are from the rust. Sand blasting is typical for rust removal. But one must take extra pass with a fine enough sand such as glass bead to insure the pits are devoid of tiny corrosion. A epoxy prime, followed by urethane will give insurance, keeping moisture from re-attacking the metal.

I suggest you "smooth out the metal" so pits are not visible. CDCIF judging will yield deducts for surface deterioration.

I also suggest to you the original coating was not very durable. Any new tech coatings should offer far better protection but may suffer deductions on flight judging attempts. Most restorations in this area are not restored, but refurbished or rebuilt to suit owners taste. In fact it has become so common place to make it better than original that deductions are rare for doing so. This can be said for most areas for almost all "restored" Corvettes.

Thanks Gene. You are absolutely correct, the rust was left in the deep pits. I knew it was there and took a chance covering it with the etching primer. Now I need to decide if I should fix just those troubled areas or remove all the self etching primer before coating with epoxy primer. I'm a little concerned about leaving the self etch in place as some have said the epoxy primer must go down on bare metal.

[Dan D.]

Re: 64 chassis restoration

Greg,

FWIW, my opinion would have been for POR-15 over the bare metal. The rust pits would not have bleed through that paint, and it gos on thick enough to probably at least partially filled the pits. But that would have been over bare metal. Not sure of it over the primer you used.

Some people on this forum do not like the POR-15, but I'm telling you is is extremely tough and durable, and will go over rust and still seal against moisture penetration. It is ideal for a steel frame that sees all kinds of abrasive elements - sand, dirt, water, stones, etc.

-Dan-

[John M.]

Re: 64 chassis restoration

Greg,
I have used epoxy primer on two cars with good success. My topcoat was John Deere Blitz Black but there are many choices. The frame was blasted with crushed glass for $300. The finer material does a nice job on the nooks and crannies but in my opinion you'll never get it all and should not worry about it. I know you're not going to drive in snow, salt and rain...
The epoxy was Martin Seynour. Wear a respirator, nasty stuff and expensive, but tough as nails. Blitz Black is $13/ quart.
John

[Tony S.]

Re: 64 chassis restoration

I'm in the POR 15 camp too. I think it's a great choice. Be sure to get the right gloss level. Tony

[Mike E.]

Re: 64 chassis restoration

I blasted clean like yours. Then several coats of Eastwood epoxy primer sanding with a DA between to fill the pitting. Topcoat with Eastwood ceramic semi gloss 2K chassis black. The last photo was shot the day after the frame was painted and the gloss level tone down a bit over time. I would NEVER use Eastwood products on a body for a chassis their produce seem to work well and is reasonable priced. For black out, since that seems to be controversial at this point I would hold off applying to the chassis until the body is ready to drop back on the chassis.







Mike