Cut and paste fender welding advice

[Challenga]

I am about to cut two fenders up and make them into one.  Doe anyone have any tips?  I am thinking that the best and most structurally sound way to do it is to cut from the top of the wheel well up to the body line and straight back to the door, then I have a little forgiveness at the top body line with the weld.  I am a little worried about the weld above the wheel being weak.  Any suggestions.  I have attached a picture of my "good" fender.  Tell me what you guys think.


Ben

 

[Topcat]

Look at these pics when I grafted two together.

I used C clamps and sheet metal screws to position, align, and secure. As you cut thru, you spot weld ocasionally to keep alignment of the gaps consistent.

Too tight a bend like 90 degrees might create problems in getting a perfect panel over panel alignment.

Bottom line... take your time and study as you go.

[Challenga]

Topcat - So those are butt joints on the steel then?  It looks like you stayed about 1/2" down from the body line.  That seems like some good advice.  I'm going to do the same thing.  I think I am going to do all of my aligning and welding on the car.  I am going to take my time for sure.  Thanks for the pics and advice. 

[Topcat]

It's kind of hard to explain on doing this. But hopefully the pics give you the right idea.

So what I did was I layed the good portion right over the top of the bad portion. Then I C-clamped all around.

Careful! don't get over zealous tightening them down. In areas where there was a alot of curvature; I used sheet metal screws to tighten up any gaps between the two panels. As I cut thru both, I would ocasionally put a weld ajoining the new donor panel and still good sections together. This way, they couldn't spread apart and screw up both of the panels on their alignment with each other that I set up. If ajoining a re pop section to an OEM panel, it's important to really go over all the contours. Re pops aren't as accurate as many will tell you.

Make sure you quench welds with air everytime!

It took me about an hour once set up getting the transplant completed. So it's not really complicated. Just detailed type of work where you need to pay close attention to where you've been and what is next.

[Topcat]

One more thing.
I used the blue scotch tape as a guide line as I cut thru both.

[Challenga]

Great.  I am going to give it a shot.  I'm going to use your plan of attack exactly.  I'll let you know how it goes.  Thanks again for the tips!

[72bluNblu]

The biggest issue you'll have isn't the strength of the fender, that will be fine no matter where you cut and weld it. The most important part is to make sure the fender keeps the right shape. So as Topcat mentioned, the alignment is key. Also, you're going to want to avoid warping the metal, so don't overheat the metal or work too long in one area. Making the welded area longer can help make the alignment process better, but also keep in mind the more welding you have to do the more likely the fender is to warp too.

I've worked on a few grafted fenders, and its hard to keep things aligned and warp free. Looking at your "good" fender, I'd be inclined to fix it rather than graft two together. But that's just me.

Good luck with your project! 

[torredcuda]

  I think just fixing that fender would be less work than trying to graft two together. 

[Challenga]

Jeff - Its hard to see from the picture but my fender is pretty jacked up.  Between the wheel and the door is is completely out of shape and the structural backbackbone piece on the back is crushed as well.  The fender was bent all the way up in the wheel well.  The picture above is with after some BFH negotiating and crowbar manipulation.  I was going to try to fix it, but the lines are completely gone and I am a lot better welder than a steel pounder.  I'm just going to take it slow and use a staight edge when I am lining everything up.  I'm not going to start for a week or two, but I'll post some pics on how I did it.  It will help the next Newbie maybe. 

Back to the garage....I'm wire wheeling and needle peening my trunk.  Should be a fun day...

Ben

[Topcat]

the alignment is key. Also, you're going to want to avoid warping the metal, so don't overheat the metal or work too long in one area.

Good luck with your project! 

 

Look at my settings on my welder in the picture. Notice wire speed is way up and amps are down. Probably a little too up in that pic. Play with your wire speed a little till it welds good but not too much heat. Blow compressed air on each weld for up to a minute.

Read this on how he welded.

http://www.musclecarrestorations.com/articles/tech/metal-work/welding-sheet-metal.html

[Topcat]

Here's a pic when I replaced the lower rear.