Needed help with my roof repair, it was weak and had an oil canny feel. I think I have it solved, now.

[tpj71mach]

As I mentioned in my restoration thread my roof had been pushed down somewhere in it's past life and it has buckles all around the perimeter and the whole roof seems weak. It has smileys/buckles at all four corners and across the windshield and the center brace was bent down about 1 1/2 inches. the whole roof was oil canny and would pop down with very little pressure. I removed the center brace and straightened and reinstalled and started to work on all the buckles in the sheet metal around the outer edge. I was able to shrink the metal with shrinking hammers and heat and that stiffened the roof in some areas but the center is still really oil canny. I tried shrinking the center with heat and it was shrinking up okay and seemed stiffer in the areas I was working with, but it started to sink a little and I stopped not wanting to make the panel wavy and needing a lot of filler. As it is, I cant see being able to body work this as just regular blocking pressure in the center causes it to oil can. A friend who is a body man told me that when I install the sound deadener pads it will stiffen, but I don't feel comfortable depending on adhesive sound deadener to strengthen my sheet metal.
Has anyone ever worked with this issue? And if so what did you do to resolve it? I see Dyna-corn makes a roof panel but I would prefer not to remove a rust-free original roof and replace it if not absolutely necessary.

Unfortunately I don't have any really good pictures of the before showing the buckles. These are the best I have.

 

[Sheriff41]

Check into shrinking discs, they're intended for this kind of task. Also, use your body hammer to ding the smiles and push the metal back toward the center. I use light dinging along the peak of the smile glancing the strikes toward the center of the smile's radius. Often you can work the smiles out and not have to use any, or just minimal, filler.
The center brace along with some insulation material between it and the roof will provide some support.

 

[Sheriff41]

https://www.youtube.com/@proshaper/videos

 

[tpj71mach]

Check into shrinking discs, they're intended for this kind of task. Also, use your body hammer to ding the smiles and push the metal back toward the center. I use light dinging along the peak of the smile glancing the strikes toward the center of the smile's radius. Often you can work the smiles out and not have to use any, or just minimal, filler.
The center brace along with some insulation material between it and the roof will provide some support.

Thanks for the info, I am going to try a shrinking disc, I have never used one before. At this stage all of the smileys are worked out and heat shrunk and the roof is pretty straight and the metal stiffened up around those areas but there are still oil canny areas on the roof. After watching some of the you tube videos on the shrinking disc it looks like that is what I need to do for those areas. The roof would be ready to start body work if it were stiffer so hopefully the shrinking discs help.

 

[Aus73Mach1]

Thanks for the info, I am going to try a shrinking disc, I have never used one before. At this stage all of the smileys are worked out and heat shrunk and the roof is pretty straight and the metal stiffened up around those areas but there are still oil canny areas on the roof. After watching some of the you tube videos on the shrinking disc it looks like that is what I need to do for those areas. The roof would be ready to start body work if it were stiffer so hopefully the shrinking discs help.

Mine was much the same in relation to flexing although no issues with it being bent down. I installed a good quality piece sound deadener between the center brace and roof skin with no space, so no flexing between these two. Take out the old hard piece that is in there. Then I stuck on sound deadener to the rest of the roof and then a layer "stick on" of thermal insulation. Stopped the flexing and very little heat through the roof even on the hottest of days. Of course if you push down hard enough on any roof it will flex. To locate the interior light screw holes I put two small screws into the mounting holes and left them there even until the roof lining material was finished. Cut a small cross in the roof lining where the screw heads are, take out the screws and then mounting the interior light is no problem. Make sure the cable to the light is also protruding through any insulation as well.

 

[tpj71mach]

Mine was much the same in relation to flexing although no issues with it being bent down. I installed a good quality piece sound deadener between the center brace and roof skin with no space, so no flexing between these two. Take out the old hard piece that is in there. Then I stuck on sound deadener to the rest of the roof and then a layer "stick on" of thermal insulation. Stopped the flexing and very little heat through the roof even on the hottest of days. Of course if you push down hard enough on any roof it will flex. To locate the interior light screw holes I put two small screws into the mounting holes and left them there even until the roof lining material was finished. Cut a small cross in the roof lining where the screw heads are, take out the screws and then mounting the interior light is no problem. Make sure the cable to the light is also protruding through any insulation as well.

Thanks for sharing your experience with this issue, I was hoping someone else experienced a similar issue with their roof.

 

[turtle5353]

I had a hood that was oil canning really bad before. I tried everything with no luck. Just wasn’t anywhere for the excess metal to go. I ended up breaking out the grinder with a whiz wheel and made a cut in the middle of the divot. Then I welded up the slice and kept cooling it with a wet rag. the heat of the weld pulled the metal together and the cold wet rag shrunk it. No more oil canning and I was able to finish the body work.

 

[tpj71mach]

I had a hood that was oil canning really bad before. I tried everything with no luck. Just wasn’t anywhere for the excess metal to go. I ended up breaking out the grinder with a whiz wheel and made a cut in the middle of the divot. Then I welded up the slice and kept cooling it with a wet rag. the heat of the weld pulled the metal together and the cold wet rag shrunk it. No more oil canning and I was able to finish the body work.

Thanks, I had thought of that but was trying to avoid slicing and welding if possible.

 

[Doug's 73 Mach1]

If your working on a Sports Roof or Mach 1. Those that came with the optional 3/4 vinyl roof have an extra support brace directly under the rear edge of the vinyl where the finish molding mounts (right at the back edge of the drip rails). If you could find and install that brace it would stiffen up the roof panel in that area.

 

[tpj71mach]

If your working on a Sports Roof or Mach 1. Those that came with the optional 3/4 vinyl roof have an extra support brace directly under the rear edge of the vinyl where the finish molding mounts (right at the back edge of the drip rails). If you could find and install that brace it would stiffen up the roof panel in that area.

That's a great idea! I think that would work well and where that rear vinyl top molding would go is exactly where the roof seems weak still. I wonder if one of the suppliers have a parts car they are willing to sell the brace out of. I think Mike from Motor City Mustang has parts cars, or is it Don from Ohio Mustang? I will try to reach out to them to see if either has one of those.

 

[roadwarrior]

I have similar issues on my Sportsroof, previous owner carried heavy gear strapped to the roof, so the center support is bent down over an inch. Was thinking of doing something like this to stiffen it up:

https://www.jefflilly.com/build-project/1971-mustang/71-mustang-roof-support/
And if you know someone with a stud welder, they might have the shrinking attachment, allows for spot heating points to shrink the metal in a more controlled manner than a torch.

Best regards,
Tom

 

[tpj71mach]

I have been using a stud welder to shrink the smileys but when I tried it in the middle it seemed to sink the metal and I was worried about making it too wavy. The custom roof support idea seems like it would strengthen the roof very well.

 

[Doug's 73 Mach1]

All Mustang coupes came with a roof reinforcement (same one used on Cougars). One of those modified to fit a Mach 1 might be an alternative to the Mach 1 3/4" vinyl roof version. I think (but not certain) the Mach 1 roofs are lower and flatter than coupe roofs, so the reinforcements may be arched differently.

 

[tpj71mach]

Thanks for all of the insight and suggestions guys. I bought a shrinking disc (Sheriff 41 suggestion, thanks) and started with that and then broke out the torches and heated up and water cooled and then a little shaping with the body hammers and then back to the shrinking disc and I think it is much better. I plan to add sound deadening pads to the underside which will stiffen up the metal a little more and Motor City Mustang has a 3/4 vinyl roof fastback ( Dougs 73 suggestion, thanks) and he is willing to sell me the extra support out of that, so once the sound deadener is installed and the extra support is welded in I think it will be stronger than it was 52 years ago and ready for final body work.
Here are two videos of it so far of me pushing harder than you would ever normally would. I wish I had taken video of it before to show how stretched it was.

View attachment IMG_7604.MOV

View attachment IMG_7606.MOV

 

[mach71351c]

Oil canning roofs on 7173 is comen. I've seen guys add another cross brace to stop it. I sprayed Lizard Skin heat and sound coating on mine. It maid a bid difference.

 

[James Bond]

Oil canning roofs on 7173 is comen. I've seen guys add another cross brace to stop it. I sprayed Lizard Skin heat and sound coating on mine. It maid a bid difference.

Do you have an opinion on which is better, the Lizard Skin or the sound deadener pads for our cars?

 

[tpj71mach]

Do you have an opinion on which is better, the Lizard Skin or the sound deadener pads for our cars?

I prefer sound deadening pads personally but both are good for this. I have always used deadener pads because that is what a lot of new car manufacturers used on the newer cars but they are starting to use spray on deadening products in addition or sometimes instead of pads.

 

[mach71351c]

Do you have an opinion on which is better, the Lizard Skin or the sound deadener pads for our cars?

I put a Lot of thought into this. You just can"t get pads in all the cavities. I can say it maid a huge difference in the hollow sound in the bear shell when closing the doors.

 

[tpj71mach]

Thanks for all of the insight and suggestions guys. I bought a shrinking disc (Sheriff 41 suggestion, thanks) and started with that and then broke out the torches and heated up and water cooled and then a little shaping with the body hammers and then back to the shrinking disc and I think it is much better. I plan to add sound deadening pads to the underside which will stiffen up the metal a little more and Motor City Mustang has a 3/4 vinyl roof fastback ( Dougs 73 suggestion, thanks) and he is willing to sell me the extra support out of that, so once the sound deadener is installed and the extra support is welded in I think it will be stronger than it was 52 years ago and ready for final body work.
Here are two videos of it so far of me pushing harder than you would ever normally would. I wish I had taken video of it before to show how stretched it was.

View attachment 78204

View attachment 78202

I added the extra supports that I got from Motor City Mustang, It's probably overkill, but I feel a lot better about going forward and finishing body work on the roof now.

 

[PoFoMoCo]

Well done. You’ll be through with that roof body work in no time! Soon it will be time to mix-up some Wimbledon white paint for this bad-boy! Let’s go!!!