whats the best way to brace a soon to be convertible?

i have a 51 chevy that will soon be becoming a convertible what/how do i need to brace this bad boy up so i will still be able to open the doors, have good fender gaps, ect. ect. whenver it doesnt have a roof?

any input would be very helpful.

thanks

 

Box the frame rails
Tie the door jambs to the floor bracing
Add a sheer panel at the door jambs and cowl
Beef up the windshield posts and header.
Brace it up before you cut This apart.
Easy

 

thanks. i knew i needed to brace it before i started cutting.

 

It would seem to me that you would want to reinforce the frame to stop any flexing and keep your doors shut. Also on a 63 t-bird that someone had removed the roof they put cross bracing in the area under the package tray, once again to stiffen up the body. Good luck, Mike.

 

^^ frame rails are already boxed.

'verts have a big heavy X holding the frame together.

'verts have a brace inside the floor that goes from one side to the other a couple inches in front of where the rear seat riser is... they also have a pretty heavy gauge L bracket right at the rear part of each door jamb. been a while since I spent any time around a convertible, but I'd guess the whole interior part of the quarter panel is different. not sure what they have to strengthen the firewall from flex, but I'd guess there is something there as well.



IMHO there is no better way to ruin a car than to cut the roof off.

 

Look closely at a Chev convert if you can. I would guess a large "X" member in the frame, as well as increased gages on side rails. You need to increase rocker section strength - if you are replacing rockers on the car - hide a length of 2X3 or 2X4 tubing in there - tied into the body structure - works wonders (did that on my shoebox convertible). Windshield pillar also needs strength.

 

A convertible parts car would be nice to have, but also hard to find.

 

I had a customer's 56 Ford ragtop that had a history of problems with alignment, doors not opening/closing, etc.
Even though I probably fixed all the problems that might have caused these issues, bad body mounts, rotten floors, I decided to try and make the car even better than original, and brace it up more.
Before installing rockers, I welded in a 2 x 2, 16 ga., steel square tubing to the inner rockers, and sill plate area.
I ran a 1 x 1 1/2" tubing up the door jamb, to just below the lock, welded to the inner, and the jamb, and the 2 x 2. Then tri-angulated a piece of 1 x 1 from the top of the door jamb brace to the inner wheel well. Be careful here, to avoid interference with the workings of the quarter window, I had to curve this one slightly. The car had an extra brace under the back seat., I made one out of tubing, taller and stronger than original, and tied it to the door jamb brace with some 1/8" plate. That's all I could fit in.
A brace was welded in across the bottom of the dash, as well. I probably could have welded in another 1 x 1 1/2 in the front door jamb and tied it into the dash and cowl, but I thought the area was probably strong enough already. But it couldn't hurt to do so.
Most convertible versions have the huge X frame, as has been mentioned, easy to fab one up. I like using 1 x 3 top and bottom, with 1/8 plate joining the 2, like an "I" beam.
Many ragtops also have an extra 1/4" plate welded to the bottom of the existing ch***is for support, as well. Runs from under the rear spring mounts, right up to where the lower A frames mounts.
Lotsa work!!!!!!

 

The 49-54 Convertible frame has a big I-beam X added through the center of the car, roughly from the cowl to around the rear spring perches. I've sold several of them. The stock frame is pretty flexible, they do need the bracing.

 

Maybe BobK will see this. If not pm him as his vert was a hard top to start with