I am in the process of replacing the header bar on my '71 due to the infamous rivet bumps and corrosion on the header bar. I already have the header bar off and I am removing the rivets from underneath in accordance with the instructions provided by Willcox. The thing is that I am not very confident that all the bumps will dissapear when I push them down with clamps during the curing procedure of the SEM glue and because of this I am trying to fix them a little bit before I put the new header bar on. I am heating a bit the fiberglass and push them down with clamps for a long period of time with no luck, they came down a little bit but not as flat as I would like. The reason for this could be that because I am not using any glue as soon as I remove the clamps they pop out again. I've noticed as well that the bump area on top is slightly bigger that the area I remove of bonding strip to remove the rivet head an corrosion so maybe there is a bit of corrosion traces under the bonding strip I didn't remove yet. What could you recommend me?

Thanks in advance.

 

I am doing a body off restoration on my 72 and removed the header bar and the rivets. Its been about 2 years and the bumps have not come back. The fiberglass on the top is flat.

 

But did you fix the rivets prior to bond the header bar back on or just bond the header and clamp it at the same time?

 

Removed the rivets and bonded header bar with epoxy

 

Go read this...

http://repairs.willcoxcorvette.com/w...stallation.pdf

Willcox

 

The Willcox article above provides some good information. When I replaced the Header bar in my 78 (no rivets thank god), I also used a trick I found on the forum that I have not seem mentioned in any comment on this thread.

It's important to make sure you do not squeeze out all of the adhesive when you clamp in the new header bar. To do this, I inserted small flat washers along the header bar every 8 inches or so along the surface to be bonded. This ensured that the clamps would only compress the header bar until it was pushing on the washers, leaving at least a washer's thickness of adhesive between the header bar and the original fiberglass. This will compensate if you accidentally tighten the clamps a bit too much.

Good luck

 

the rivet pops on my 68 were the worst ive ever seen, i took a small hole saw with no center drill bit, put tape on hole saw so i dont go too crazy and drilled all of them out from the underside, had to use right angle drill to get the ends, pryed the rivets out with a needle nose vise grip, popped header bar off and glued back on with 8115 2 part epoxy, i tryed the heat gun and tried to push the rivet pops down and they barely moved, however when i glued the header bar on i used a plank on each side and 20plus clamps to hold the bar to the nose, when i removed the clamps the pops were almost. gone

 

There are a few options that folks will give but what works for me is using my heat gun and heating those bump areas a little and taking a teaspoon and pressing down to create a dimple. This allows me to then come back with VPA and fill those areas. Some will sand the bumps down thinning the fiberglass in those areas which I would not suggest. The dimple method still allows the fiberglass to maintain at least a better thickness. Works great for me as this option was given to me by Dub who I consider to be well versed it many of these type repairs. Your car do as you may, just an alternative.

RVZIO




69 project that I used VPA after inking down the bumps.

Spoon is upside down but shows the right size dimple.

71 project where bumps were not real bad but used the process anyway.

71 finished product

69 finished product

 

I have owned my '72 since '95 and in that time frame, it's been sanded/painted twice, so the question is on those bumps, that header bar never been outta there, far as I can see the rivits still there....

Can I re use the header bar in there now?? if I ever need to redo the front again?? far as I can tell, it's not rusted out and the lights bolt in just fine....

 

mrvette,

It’s not rust that is the problem, but two different metals reacting to each other. I’m in the process of finally getting my ‘72 painted and we are addressing the header bar. I will also replace the header bar on my ‘70 next. I purchased a new one from Willcox.

I like what Roger did with the spoon. I learn something new every day.

 

If the header isn't rusted then yes you can split the aluminum rivets and remove it (and the rivets). If you look at the pdf I posted above I believe you'll see a picture of the tool we made for doing this job on page two. The trick is that this is a very old putty knife that is very thick so you'd need to make something similar to this, then get it between the header bonding strip and us it to cut the rivets loose. Then clean everything up.

When we glue the new header in place we typically put the glue in the holes that are left after the rivet is removed, then we try to clamp on top of the area the rivet was removed from.

Willcox

 

Since the header bar is supporting your headlight assemblies it is critical that a new one or whatever be put back in the same location. With that in mind I transfer lines from the one installed and I do leave some of any adhesive that has oozed out to get my proper alignment. Assuming your light gaps were okay. You do have some small adjusting in the light assemblies but not a whole lot. Thought this may help also.................................... .....................................

RVZIO

 

The later model cars actually have lines on the bottom of the surround panel to give you a good idea where the header belongs. But when you remove the header from a 1968-1972 car you'll have awesome witness marks. But it's always a good idea to make your own so that you can make sure you get the header in the correct place. I was tired last night when I posted and it was brief, but if you have any questions feel free to email me after Monday at service@Willcoxcorvette.com. I'm on the west coast until then and have limited access.

Ernie