I have a couple of questions on putting the roof skin on. #1 what do you put between the center support and the roof? #2 Has anyone used panel bond to attach it to the drip rails?
I am getting close to this chore myself. I believe the proper thing is to put in a thick bead of sealant on the supports when laying it in. Once dry, it should not only seal but prevent rattling. As for the sides, front and back, it is my understanding the lips gets spot welded to the existing frame around the perimeter. The front and rear pillars get welded in followed by lead to smooth the seam out. That was going to be my plan of attack.
To answer your question about panel bond, I haven't used a product by that name but I have used one called Lord Fusor 112 which dries very slowly and also permits spot welding as it dries without popping or burning too much. They refer to it as a weld through sealant and I guess it was designed for repair shops.
I'm gonna have to throw in my 2 cents on this one. Do NOT use panel bond on the center support for the dome light! Trust me, I found out the hard way. Half the time when you take a good look at one of these E bodies, the factory sealer on the top of the center support for the dome light has already broke away years ago. I used about the same amount of panel bond on the top of this support only when installing a new AMD roof skin. The rest is plug welded in the same spots as the original spotwelds. Well, after moving the car around on dollies and transporting it to the paint shop, the roof buckled right where that brace is! My guess is the body flexes a little bit and it was definitely too tight in that area. Had i used just plain seam sealer, it would have likely just broke away from the roof.....same as it was. Lol. Lots of work to clean up that roof skin and make it right.
I put a roof on my Cuda. I only welded on the front, back and sides. Center supports have nothing. I was told by Craig from AMD to ( if you're mig welding) to drill holes in the drip rail and weld from the bottom up to the roof. Don't know what you're working on but on my Cuda the fit was perfect. I don't know if panel bond is a recommended method but it sure would be easier if you could use it on the drip rails. I'd call AMD and ask them first.
So the center support gets nothing? One of the things I noticed on my roof was the rattling where the old bond came loose.
Thanks for that info Six Pack70. I could see how that could happen.
No problem...this is how we learn. I wouldn't use nothing at all on that support just something flexible....and a very small amount. :bigthumb:
OK, ever the contrarian, let me put my :alan2cents: worth in here. If you have a car, that while moving it ( and I'm assuming you didn't use a crane to pick it up) and the roof skin buckles because you bonded it to the roof ribs, then you've got other issues to worry about. These cars are semi flexible, but the factory put sealant in there for a reason and you should, too. Personally, while my roof never came off, I did replace the sealant with new and actually made about a 4" band to go inside the roof that I adhered to it, to stop a potential oil canning that I didn't like, and several thousand miles later, there's no problems. Perhaps a middle of the road solution would be to use a flexible sealant? Your car, your call. Good luck. :cheers:
I agree with you about the factory application of sealant. Not todays panel bond. I also agree with you that these cars flex, which is my guess why most of the Cudas and Challengers I've encountered have this center brace already broke away from the roof. Was it crappy sealant? Was it the body flexing that makes it lose it's grip? Who knows. Please dont get me wrong, my roof was not buckled to the point where i thought i might have bigger issues. It more or less left a visible mark where this brace is located accross the AMD roof skin. Also something to keep in mind, the AMD metal is not the same as the original metal. You can bend it quite easily with your bare hands. I'm only saying what happened to my professionally installed roof skin. Had i given it more thought when the roof was going on, I would have just brushed some 3M flexible seam sealer on the brace instead of two part panel bond which pretty much welded it to the roof. Before bodywork is completed on the car, I will likely be carfully cutting it away from the roof skin.
My roof oil cans pretty bad now which is why I'm going to replace the skin. I believe it is because it was a vinyl top roof that had lots of rust in and out so I sand blasted it clean. I think between the rust and the sand blasting, it's just too thin now. The sealant across the support wasn't holding either but in looking at it, the factory didn't use much. I resealed it and it helped but not enough.
My plan of spot welding around the perimeter remains the same but I'll have to think over the center support. My gut tells me the factory did it so I should.
How about foam strips, like what is sold at hardware stores? :alan2cents:
Sealant and adhesive are two different things. I'd put flexible sealant on it and not worry. Bonding it will give you issues and likely read-through, if nothing else.
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Quote from: JS29 on December 27, 2018, 07:10:40 AM
How about foam strips, like what is sold at hardware stores? :alan2cents:
The thing that concerns me is that I worked on my roof until the oil canning was almost gone. Then in the morning when it was cold, it was back big time. I don't want to ever have that issue with temp changes. I can just picture my roof popping down in some spot and staying that way, unable to pop it back up because the headliner is in the way.
So, no one has tried to panel bond the drip rails instead of welding? I plan on plug welding the window frames and sail panels. Just not so sure of my welding skills on the rails.
Quote from: truckinman466 on December 27, 2018, 12:40:50 PM
So, no one has tried to panel bond the drip rails instead of welding? I plan on plug welding the window frames and sail panels. Just not so sure of my welding skills on the rails.
I have used a type of bond on metal before as a test and found it's not that hard to pull them apart. Probably stronger as a shearing effect but I'd weld them in.
There are quite a few oem manufacturers who bond on roof skins these days and you can bet your bottom dollar that if there were even a slight chance of the roof coming off their cars, they sure as hell wouldn't be doing it. Having said that, I'd use a blended system. Bond the skin on and leave a few prepped holes to put in those few spot welds. That's what many collision shops are doing today. Have your cake and eat it too. :cheers:
Quote from: jimynick on December 27, 2018, 09:02:04 PM
There are quite a few oem manufacturers who bond on roof skins these days and you can bet your bottom dollar that if there were even a slight chance of the roof coming off their cars, they sure as hell wouldn't be doing it. Having said that, I'd use a blended system. Bond the skin on and leave a few prepped holes to put in those few spot welds. That's what many collision shops are doing today. Have your cake and eat it too. :cheers:
:iagree: Ben there done that! I use 3M panel bond.
The real panel bond stuff is pretty permanent.
Quote from: JS29 on December 28, 2018, 05:45:13 AM
Quote from: jimynick on December 27, 2018, 09:02:04 PM
There are quite a few oem manufacturers who bond on roof skins these days and you can bet your bottom dollar that if there were even a slight chance of the roof coming off their cars, they sure as hell wouldn't be doing it. Having said that, I'd use a blended system. Bond the skin on and leave a few prepped holes to put in those few spot welds. That's what many collision shops are doing today. Have your cake and eat it too. :cheers:
:iagree: Ben there done that! I use 3M panel bond.
The 3M is generally considered to be the gold standard for bonding material, but I've also used Dominion Sure Seal and Lord Fusor with no issues to date. I actually used the 3M also as a seam sealant when I put in the new floors. I didn't want any BS down the road and even though it IS pretty dear, I feel it was worth it. As the Brits would say- bit of a sticky wicket, what? :D
I did a 1970 Barracuda AMD roof skin and used a spot welder every where it was the best way minimal heat, zero distortion and no grinding plug welds after. I did have a problem with the centre brace it was pushing the skin up in 1 spot and there was a dent there, I had to drill the spot welds and remove the brace as soon as it was removed the dent disappeared so I tweaked the brace and applied normal seam sealer to it and plug welded it back in. It was perfect and the seam sealer is very strong while still being flexible. There is an excellent video on you tube if you google 1973 challenger roof skin you will find it was posted by jamesfreddys I watched it a few time before I started.
Hope this thread isn't so old that no one responds to it anymore....I spot welded my new roof skin on yesterday and it came out perfect. I used a flexible sealer across the middle support and I think that's going to work out great.
My question now is what seam sealer would be a good choice to apply to the side rails on top to cover all the spot welds and make everything nice and smooth? The sealer I used on the middle support is far too thick to use for this. I was hoping for a product that has a thin consistently so I can smear it into the nooks and crannies. It would need to be sandable and paintable. The factory had something in there before and I remember digging it all out. Any specific product suggestions?
I went ahead and ordered up some Lord Fusor 122 ez. It is supposed to be a self leveling seam sealer designed for roof rails. Plus I already have the correct gun.
Grease and wax remover, the stuff one would use to wipe down a surface before paint will keep seam sealer ply able. so you can work it, and it also thins it. I also use an acid brush, masking tape, and lint free shop towels. after it sets up you can give it a good couple of coats of urethane primer to finish finessing to perfection. :alan2cents:
Quote from: JS29 on May 19, 2019, 12:12:55 PM
Grease and wax remover, the stuff one would use to wipe down a surface before paint will keep seam sealer ply able. so you can work it, and it also thins it. I also use an acid brush, masking tape, and lint free shop towels. after it sets up you can give it a good couple of coats of urethane primer to finish finessing to perfection. :alan2cents:
What if it's the seam sealer you apply using a caulking gun?
122ez is great, used it on my drip rails. It may start to creep down on the quarter window slope so tape/paper off where you don't want drips or over application. Use a gloved finger dipped in W/G remover to smooth out as mentioned by JS29. :alan2cents:
Quote from: shawge on May 20, 2019, 09:32:46 AM
122ez is great, used it on my drip rails. It may start to creep down on the quarter window slope so tape/paper off where you don't want drips or over application. Use a gloved finger dipped in W/G remover to smooth out as mentioned by Rdchallenger. :alan2cents:
Glad to hear it. Thanks for the feedback on this! I should have the stuff by next week so I'll give it a try.