Frame off question?

[Vin's 49 Plymouth]

Hello everyone, I have it in my mind that I would like to do a frame off restoration, and hit a point where I have to repair the floors and sill plates. Do I cut and weld with body on frame or wait until its off frame and on stands. As an Aircraft Mechanic, I think it would possibly change shape after being unbolted? But the MOPAR man side of me says just do it and don't worry about, it's heavy duty Plymouth/ Briggs body will stay right.

So besides not cutting into the support structure and letting my tack welds cool, what other advice would anyone give? I teach an Aerospace fabrication class, so fabrication is my bag, but I want to do this right and to factory specs. Any thoughts?

 

Thanks so much!

Vince

 

 

[Plymouthy Adams]

your call...the body will move with welding heat..a bit outside of aircraft rivet operations...I personally do not remove the body till at minimum the rockers are solid inside and out and to do that I also do not remove the doors as this is your test alignment during the operation.  ensure you hinge pins are good...no wear/slop and then adjust your door within the opening for the gaps that you wish..if you have sag now ensure you do not have a buckle at the roof and align front and top gaps of door and adjust your rocker with jacks or braces of your design or choice so to maintain the gaps you are wishing to achieve..afterwards adjust your striker to ensure smooth operation...once set up..you can remove the striker for ease of opening and closing during the process to verify that you are staying aligned during the replacement of metal..other folks have other ways of doing this I am sure but this has served me well in a number of full inner and out rocker repairs..many may respond with other methods..pick what may suit you the best..keeping the car in a fixed position during the repair is important...do one side at a time...

[casper50]

I took mine off for access but I welded 1"square bracing across the doors and from side to side.

[DonaldSmith]

Hemmings Classic Car magazine features full restorations.  The door openings are usually braced well, especially if the sills are rotted. 

 

Incidentally, Classic Car gets into a snit over the language.  They insist it's a "body-off" restoration,not "frame-off".  I guess it all depends on whether the body or the frame is the center of the universe.

[Young Ed]

Just call it an off frame then it works right?

[desoto1939]

As stated above prior to take the body off the frame you should brace the the body especially where you will be cutting out the bad floor material. This way you have the car in alignment or so as to how the car is currently positioned and then when you cut out the bad metal the car will not shift on you and then be out of alignment.

 

If you do the repairs with the car on the frame still brace thee door opening so they do not move you might get away with just a pressure fit brace instead of a welded brace not sure but when cutting out major metal need to insure the opening around the are  do not shift.

 

Rich HArtung

desoto1939@aol.com

[Vin's 49 Plymouth]

Thanks for all the idea's, now I have to choose. But most of all I will weld a stiffener brace to hold the body in a fixed position as recommended.

 

Does anyone know how much the body weighs? (4 door sedan)

 

Vince McLellan