I have a question I'm hoping someone may be able to give some advice on. I have a rusty F1 that is in dire need of some rust abatement. I began attempting to fabricate a piece for the lower front fender the other day and realized I already had a snafu. The top edge I’m trying to mate to has a slightly radiused edge, I was making the new piece by butting the two and welding which resulted in a fairly severe edge condition. My question is how should I go about getting that radius? Do I fill it in by welding and then grinding, do I grind out that area and weld in a small patch to give it that curve, or do I just take a hammer and dolly to it and try to get it in shape. I know next to nothing about body work or welding so please dumb down your answers. This is my first attempt at either. Attached is a picture of exactly what I’m talking about.

 

get a solid metal rod about 1'' in diameter. about 4-5'' long. weld a piece of metal plate to it about 6-7'' long and a couple inches wide. weld it to make a T. put that in a vise. before your weld the two pieces together on your fender. hammer your radius on the bigger or front part of the fender then weld the lip to that. hope that helps. shawn

 

Thanks Shawn. That's exactly what had come to mind to me was to make a sort of custom dolly. I had no idea something like that could even be bought. I don't think the radius is that great and was thinking of using some rebar I have around. Fortunately, I'm probably starting with the most difficult piece to repair, aside from the driver's side which will need the mirror image of this, everything else will be more of a square cut patch. At least that's what I think right now. I'm sure I'll discover other challenges as I go.

 

Those dollies can be bought, Check out Ron Covell or Rob Fortier's web site. It's pretty easy to make them tho, round over the ends of the rods so it doesn't scar the panel. (Don't use the rebar, use smooth rod) The way I would have made you patch piece is by making a hammer form: Carefully cut two pieces of MDF board the shape of the flat piece less one thickness of metal. radius the edge of the MDF to match the radius you want by sanding or better with a router. Cut a piece of metal ~ 3/8" larger than the finished piece along the radiused edge, and clamp it between the two pieces of MDF as tightly as possible with as many C clamps and/or deep reach woodworker's clamps as you can fit on it especially in the center near the edge, the tighter you clamp it the better and easier the result. Use a curved faced body hammer or a nylon faced hammer to begin bending the lip over the edge of the form. Start in the concaved part and work out, don't get greedy and try to bend it all at once, but bend a little at a time in a 1/2 doz passes along the entire edge and it will bend as nice as can be. After you have bent it down smoothly along the entire edge, unclamp it and trim the edge straight. Now all you need to do is bend a piece of flat strap and weld it to the radiused edge to complete your panel. If you radiused both pieces of MDF you can flip them over to make the mirror image piece. Covell and Fortier both sell some excellent videos on making patch and custom panels. I highly recommend Covell's "basic metalworking techniques" and Fortier's "hammerforms" as minimum must haves for the novice bodyman.
The other must learn technique is the difference between "on dolly" and "off dolly" hammering and when to use each or you will do more damage than good on your truck. Covell talks about it on his video.

 

I had to read AXracer's post twice to get it but that makes a lot of sense and I have a little more experience with woodworking......So! Thanks for the tips I'll give that a try.

 

As you get more experience with hammerforms and how to use them you'll figure out all different ways they can be used. They work very slick!

 

Nice job on the panel you made.
Before welding the top and side together, you could use the above mentioned method to radius bothe edges before welding. This way, once welded, you could sand the welds down and have a nice smooth radius.
Your going to have trouble getting thae weld smoothed out since it is harder than the surounding surfaces.

 

Yes, and for that reason I'd make the complete radius (90*) on one piece then joint it to the second piece after the radius rather than trying to fit and weld down the center of the radius bend. I also use Esab "easy grind" wire in my mig, it is softer and more ductile which allows hammering directly on the weld to stretch out shrinkage without cracking the weld, as well as making metal finishing easier.

 

if i see what i think i see you trying to do the easyest way is to run a bead wild. round it with grinder then bondo and shape it to perfection.