When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
How does one fix this? I have a feeling this is a real expensive question to ask.....
As probably has been told a million times before. These are the alu rivits corroding an popping the paint up. Grinding, removing, and then depending on whether or not you want to stay original, put in new rivets that will corrode again over time. (you got to love the car.
If not trying to stay original, grinding, removing the rivets and glueing the bar in place.
Anyhow, you get to repaint the car, unless you stick with the bumps as per original.
Hi Dan
Looks like a NICE car!
Since the rest of your car looks so good I wouldn't worry about the appearance of the rivets. The rivet bumps seem to be most obvious on dark colors, and in certain light.
I've found that very original cars show the rivets even if there is no rust on the support bar or oxidation on the aluminium rivets themselves.
Some people view the bumps as a badge of honor. Here's a picture of a repair of rivets that weren't rusty or too 'lumpy'. It was being done only because the car was being painted.
I think I'd first get a good look at the headlight support bar under the fiberglass hood surround to see if rust is present before deciding what if anything to do.
Regards,
Alan
Remove headlight header bar and bonding strip. Drill out the rivet heads holding the bar to the bonding strip.
Reinstall.
Sounds simple enough but it's a big job.
Mike-
We used to remove the bonding strips with the header... but we changed that a few years back.
You guys will see why in this new file I just finished! Take it easy on me I've not proof read it. This thread popped up this weekend and we just did this job last Monday.
Now as you may guess, I'm NOT a huge fan of drilling the top of the surround panel to remove the rivets. It is not the proper way to do this repair and will come back to haunt you. IMHO
Willcox Inc.
Last edited by Willcox Corvette; Aug 1, 2011 at 04:52 PM.
We used to remove the bonding strips with the header... but we changed that a few years back.
You guys will see why in this new file I just finished! Take it easy on me I've not proof read it. This thread popped up this weekend and we just did this job last Monday.
Now as you may guess, I'm NOT a huge fan of drilling the top of the surround panel to remove the rivets. It is not the proper way to do this repair and will come back to haunt you. IMHO
Willcox Inc.
I agree, thats how I did it, except I just drilled the part of the rivets that come through the header bar (making sure not to drill through the rivets) and was then able to remove the header bar.
After that I did it the same way as Willcox, though I did fill the holes left by the rivets (making sure not to put too much filler in there so the bumps won't reappear) before gluing the headerbar back on.
The fiberglass guys I have talked to all agree, there is no way to fill a hole in a fiberglass panel without it eventually reappearing.
I am happy see you post this Willcox. When I tried explaining this the last time I got flamed by people claiming that some of the new magical fiberglass panel hole filling materials you guys in the US have probably just hadn't made it to Europe yet ;-)
Last edited by Danish Shark; Aug 2, 2011 at 04:57 AM.
Let's not forget that aluminum and steel are dissimilar metals. When these two metals are put together, they will react, and there will be corrosion. I believe that the factory used the aluminum for ease of assembly and to save weight. It is my opinion that GM was not concerned about the long term effects. By the time problems arose, the vehicles would then be out of warranty. They probably didn't expect that many of them would be around 40 or 50 years later! While restoring my 1970, I replaced my fasteners with titanium or steel - but then I'm not going concourse.
Why did you opt not to replace the bonding strip? I didn't see mention of the reason for this change in the document. Maybe I missed it?
Leaving the existing bonding strips in place will help you locate the new header bar, which, of course, is installed after all the aluminum rivets are removed.
Chuck
How would it re-appear if you fill it with resin & mat?
The expansion and contraction ratio of the resin and mat is different than that of the press molded fiberglass, or SMC injected material. This alone will cause it to change over time.
There are other factors that play in to this such as the sun heat, and the materials used drying down after finish. In the end a hole will be seen. Or check me on this.. I'll say it has been my experience.
Why did you opt not to replace the bonding strip? I didn't see mention of the reason for this change in the document. Maybe I missed it?
It just makes the job easier, and there is very little chance of cracking the upper surround panel. When you remove the bonding strip you get a flimsy upper surround panel that can easily crack. When you leave the bonding strip in the car it gives you witness marks for installing the new metal support.
There are keys to a successful installation. 1) Make sure all the rivets are removed. 2). When you bond the header in make sure not to squeeze all the glue out. 3) Make sure you clamp over the pimple and it will compress in the new epoxy below it.
If you look at the tool we use you'll notice the sides are ground sharp. It really on takes a few pops with a small hammer to cut the old rivet out.
In the end a hole will be seen. Or check me on this.. I'll say it has been my experience.
[knock on wood] So far it has not been my experience. We didn't have to fill the brace holes as we replaced the surround and the new one was just bonded in without rivets. But there were other areas where resin & mat were used. No sign of anything popping up yet though.
Resurrecting an old thread. I have a 70 LT-1. It was painted in 1980, original Marroon color. Not a great paint job, so I may end up painting it again. Don't really know for sure. I am planning to rebuild the original motor and re seal the original trans. I am not that worried about the imperfect paint for now. Would just like to drive it around and have fun in it.
Although they don't show in these pics, I have the bumps across the nose piece. I tried to open the link to the article on the Wilcox site: Corvette Headlamp Header Bar Installation 1968-1982'
Couldn't get it to open. Also, could not find it on the web site. Would like to see a good tutorial on this before I start the work.
Any help is appreciated. Here is my car with its "little brother".
You don't want to mess with those 'bumps' unless you are planning a complete repaint on the car. If there are no breaks in the paint above them, they are sealed and all is well (for the present). The aluminum rivets used in that assembly are slowly oxidizing and 'growing'. It causes no damage, except for expanding the paint surface a bit.
Some folks keep those 'bumps' intact just to show that the paint is original to the car. (Hopefully, no one repainted the car without fixing those pesky rivets.)
Plenty of past threads, a quick search will provide lots of great info. With a little bit of luck those
bumps just might smooth back out and relax like when I did mine.
To remove header, a friend shortened and welded back together this small starret key hole saw.
Its less than 1 1/2" long, plus the pilot. Pulled the pilot down enough so it wont come out the top of the car. Used a small 90 degree
drill and it was able to get to all the rivets in the header. Then cleaned and roughed up the fiberglass strip that the header
was mounted to, along with the header itself, screwed in the mixing tip and applied Lord-Fusor metal to fiberglass adhesive in a dual tube small caulking
gun to the metal header.
Before final removal mark a few spots on the header and the car to make sure it goes back into exactly
the same location it was removed from. Before it gets bonded back up there, go to harbor freight and pick
up plenty of clamps. Use them to clamp the bar into position and on the top side to clamp wood strips over all those bumps.
Hard to believe.... but when the clamps and wood were removed, the bumps were gone like they were never there.
