Stepdown Roofs

Hey all, 
Am currently blocking my roof, and besides the occasional small crease from a bump in the past, the entire roof is barely perceivably wavy.  You can only really see it with some guide coat, but I am assuming that this is normal and just wanted to confirm with other folks. 
Thanks, 
Ray

Comments

  • Maybe not wavy, but more like ripples on a lake. 
  • Kdancy
    Kdancy Senior Contributor
    These roofs are so big, it's not surprising. Sounds like yours has had some prior damage that caused the ripples.
  • There were some creases from overhead damage in years past, but what is surprising is the flexibility of the roof.  I think the ripples might be a remnant of trying to stretch a large sheet of steel over a rounded form.  You're bound to get distortion somewhere in the metal. 
  • 7XPacemaker
    7XPacemaker Senior Contributor
    The 51 sedan that I restored had a lead repair under the original paint. I would say that the factory had a little “oops” moment. They slapped the lead to it and sent it packing. It was a nice repair so I left it there when I repainted it-
  • Lead repair we're standard body repair for years until Bondo became the normal. 
    I've met and known a few that swore to lead over Bondo. All but a few are dead now.
  • So after a week of dollying, shrinking and stretching.  Chasing highs and lows from one side of the car to the other, I am about done.  

    I have made a drawing proposing a solution.  Under the areas that oil can and immediately rebound, I propose panel bonding some reinforcement metal bows.  Approximately 1/8 thick and 2 inches wide steel bent to the specific curvature of the roof with no welding and the only physical attachment being the 3M panel bond. I am not looking to fix the roof and the issues, more akin to stabilizing it so a thin skim coat of filler or glaze will sort the darn thing out.  



    Has anyone tried a solution like this?  Pros and Cons?  I am all ears.  

    Thanks all!

    Ray


  • I think this is a good solution. Bonding will avoid heat distortion. I had a '72 Mercedes that had similar "stiffeners" on the inside of the hood because it was such a low crown panel. If you were being a purist concerning the metal finishing, the solution would be very careful shrinking in the area that is oil canning, but this is a touchy thing to accomplish perfectly because of the extremely low crown of the panel (as you have discovered!).
    I would make the stiffener bands about 2" wide & you could experiment with running a central bead or a bead on each edge to stiffen these bands sufficiently. Probably better to finish with the oil-canning areas slightly low than too high - you want to avoid having to hammer down high spots once the bands are bonded in. Should be able to finish nicely with a slight fill in those areas. Careful x-pattern blocking is your friend!

  • Several years ago I had a oilcan problem with a Model T body I did. Painted the inside with por15 and covered it with 2 layers of fiberglass matt, bonded with more por15, made it nice and solid.
  • I know this may sound weird  but how about another roof?   I have  them  but more importantly, if someone nearby can supply you with one, would that work for you?
  • Tombia, 

    Considered doing either fiberglass or a thick coat of fiberglass reinforced filler as a stiffener and was worried about stresses eventually popping it off.  The strength of the panel bond is absurd so no worries there. 

    Lance, 

    In a perfect world that'd be the ticket.  But after hours of driving, hundreds of dollars, then dozens of hours, if I can even find a suitable donor roof that was legit solid (this looked it when I bought it), this can be done for under a hundred bucks. 

    Thanks all!

  • trdrew, 

    That is exactly the plan.  Glad to know I am not 100% crazy ??

    Thanks!