I have an extra (junk) Convertible top frame for my Vette that I am planning on making into a removeable hardtop. I will not pay $2,000 for something that I can make for a couple hundred. The first step is to make the folding frame of the top one solid piece that lifts off the car so to do that I was planning on welding together every hinge. That way every pivoting point would then be solid and I would have a rigid enough "frame" to begin fiberglass work.

The frame of the top is not steel (or aluminum) like I was banking on. It is some sort of alloy or "pot metal" that was cast and therefore doesn't weld. So here is my question: How would you solidify the pivoting/swinging hinges?

I am open to all options so feel free to chime in on what you think will do the trick. I am an auto body technician so I have access to professional grade products so give me a name and part number and I can get it. I am now leaning towards 3M's Panel Bonding Adhessive. If it is good enough to glue on quarter panels and roof skins, then it should be strong enough for what I need.

Here are some pictures of the hinges I am refering to.





Keep in mind this thread is not asking for opinions on if it is worth making a top/ if it is possible/ if it should be done/ etc. That can be covered in another thread. If you have useful information I would love to hear it, if you don't then please don't hijack.

Thanks to all in advance, Mark

 

Can you weld some type of sub-frame over the existing frame to stiffen everything up with like 1/2" piece of flat steel? Almost like what you would do with a roll cage, but with flat steel?

 

Glass over the frame. Then make a new frame molded in.

Or just mold around the old frame?

 

I like your thought process, I had similar ideas. The reason I am shifting away from that line of thinking is because no matter what you can make out of steel, it still has to somehow be attached to the frame (which I can't weld to) Then I thought about making a whole new frame and decided that would be drifting too far away from the "make something cool out of an old Vert piece" idea. And while weight is not nearly at the top of my list of concerns with this project, it is still a factor and I was hoping not to add too much.

That is exactly the plan and I probably should have made that more clear in the OP. The "welded" (rather solid) hinges will serve the purpose of holding the frame's shape while the fiberglass is applied (and the top is off the car) They won't really be structural once the glass is molded over the frame.

The idea of molding over the factory frame is due to the things that are already done for me: Weather stips/seals, mounting/latching, and overall OEM fit. Thanks for the advice thus far and keep it coming in. I will add more if I am still being too vague as to the design and execution of the project.

 

Either one of the previous posts would work IMO. The cleanliness of the final product would be significantly different in both.

I think there are a number of ways to fix it. 3M panel bonding is definitely not a recommendation of mine. It's good stuff but it has it's purpose and it needs surface area to work effectively. I've tried it on similar problems and it's failed over time. I've had just as much luck using the $6 five minute epoxy from NAPA on some applications.

I'll say this: I own a full blown fabrication shop. We can make just about anything from Fiberglass to metal. If you can think of some type of bracket or something I can assist with then hit me up with a PM and I'll do what I can to help out.

Brian
carcrazydesks.com

 

You are exactly the type of person I would hope would read this and comment. A few questions if you don't mind...

"Either option" refers to (1)making a sub frame/custom frame and (2) making a mold of the OEM frame so I can produce my own fiberglass top, right? Of the two which are you refering to as far as a cleaner finished project? I was planning on using the existing frame because of the fit and finish already done and if you think I am off on this I would like to here your thinking. You are the expert and I may have over looked some things here.

Your reasoning for not using Panel Bond is why I am hessitant to try it and am asking the forum before doing anything else. When you say that you have had things of that nature fail, what aspect failed? Was it the adhession to the metal that came loose or was it the actual Panel Bond adhessive gob that cracked?

Can I PM you with further questions as the project wears on? You are a great source and I would like to keep in touch. Thanks, Mark

 

Drill them out, or grind down the pins and punch them out. Replace with nuts, bolts, and lock washers and torque them down real tight.

 

is on a wright track accept I would not drill out the pins as they provide a very strong structural point. Instead you can drill some lets say 1/8" holes and cold rivet the arms thus preventing any movement. I would think 4 small rivets around the pivot pin should provide very stable joint without sacrificing structural strength.

 

In a similar vein, I was thinking of that or possibly drilling the necessary holes and using say, 1/4" or 5/16" pop-rivets instead, or maybe a combination of the two. The bolt/washer/nut idea is not bad as they could be spot/tack welded together too.