best way to weld in new frame horns?

[Lmfp]

Ok so im about to have a shop make a couple pieces to replace the frame horns on my bronco front and back. What tge best way to do this? My thinking is just a butt weld would be a lil sketchy. Whats the best way to do this?

 

[madness]

Sleeve it and then butt weld, make sure you have the measurements right before you cut and final weld so you don't have to redo it. Should be pretty straightforward!!

 

[TwoDalesDad]

Really it depends on two distinct things.....A..Whats left of your frame horns?.....B...MONEY....GOOD WORK IS NEVER CHEAP...CHEAP...IS CHEAP....SLEEVING IS GREAT...PLUG WELD WHERE ITS POSSIBLE

 

[lonesomecur]

I would not butt weld at a 90 degree from parallel to frame. I would make 45 degree seams opposite each other. Top going one direction bottom going the other so welds were not parallel to Each other. I'd get 100% penetration and I would not sleeve it. I'd want to fit whatever aftermarket bumper bracket I choose inside. If you sleeve it you must modify bumper brackets as well.

 

[73azbronco]

I would also consider using a stock bumper as a way to hold the ends to help align everything.

 

[Lmfp]

Sleeving wont be a problem for the rear because of the bumper I have for it. I would be worried about that for the front though. But thanks thats the input I was looking ffor.im keeping the rear fully boxed in all the way to the tip. Would that be a problem in the front? Ive never seen how the aftermarket brackets work. Ill eventually be running a prerunner winch bumper in the front.

 

[sp71eb]

My frame ends were nasty when I redid mine. I used 3x4 tubing for the ends. I just welded them in square to the end of the frame. Bevel the ends of both pieces and tack them in place, then reconfirm they are where you want them. I then took some small pieces of 1/8" steel that would fit inside the tube and used them for sleves. Your best bet will be to plug weld the backer then and then butt weld your seam. On the rears I went all the way past where the rear body mount holes were and just cut holes for the body mounts in the new steel.

 

[Steve83]

If you're gonna install a front bumper, either get it now & build to fit it, or just hold off (if possible) on the fronts.

The strongest welds are the LONGEST welds. Plugs are OK, but since you're butchering the frame anyway:
1) mark center on each face of the frame horn
2) mark a few inches back on each corner of the frame horn
3) cut from each center mark to each adjacent corner mark, so you end up with 4 points sticking forward
4) insert two 2x2 square tube sleeves so they protrude past the points
5) weld along each cut to the tube sleeves (2 long welds for each of the 4 sides of the frame)
6) fabricate the replacement frame horns to create whatever end you want, and so they fit to your pointed cuts
7) weld the new horns onto the sleeves along the same welds as step #5, and along the fronts of the sleeves

Even using thin-walled square tube, that will result in a VERY strong joint, perfectly aligned with the original frame surfaces, and much stronger than a square-cut butt-weld.

This diagram shows the details of the stock frame horns. Click it & read the caption:

 

[Lmfp]

I can deffinately hold off on the front for now. The rear is a pretty big concern atm. I patched it up but I dont have much confidence in its strength bbecause of where its split. (Right at the body mount) both bbumpes were ripped off at one point.

 

[rastiss]

Sleeve with plug welds on all side then weld the seam. This is the industry standard recommended by manufacturers and I-CAR. On modern vehicles with "collapse zones", it's done all the time. Should be done by a qualified welder.

 

[Steve83]

Ford's recommendations are in this caption, and the links they came from are there, too. Ford doesn't authorize any repair to frame crumple zones - the frame must be replaced.