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Discussion Starter #1
All,

I wanted to get your opinions on what is the best way to repair a rusted out frame body mount.

I have purchased the large washers that are sized correctly for an A-body frame repair.

As I see it, there are three options:

1) Cut out a hole the size of the washer and weld it in
2) Leave all the existing material and weld it over the rusted out section
2a)Do this on both sides to make that mounting point even on both sides.
3) Weld from underneath.

I would think that option 2 would be the strongest because it would leave the most material, but I worry that there would be a space between the repair washer and the old material giving a place for more rust to occur.

If option 2 is the best, do you think that I need a washer welded on both sides to keep it even? I wouldn't think that washer thickness would make that much difference.

I have added a few pictures as reference. The first picture is the rusted mount. Second is how I proposed to weld the washer on in option 2. Third is welding from underneath, and the fourth is the mount on the other side. You can see that mount is a little rusted, but not too bad.

Thanks in advance for your input.

Dan
 

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I offer option 4... cut them both off and weld new body mount brackets on from Ames Performance. $39 a piece. Matt
 

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Have performed the first process many times on customer's frames.

Even if you are hamstrung with a minimum of tools; ie, Dremel cutoff tool, angle grinder, and a $100 arc welder, can perform a very clean repair.
 

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Discussion Starter #7
Thanks all for the input. I did briefly consider option 4, but it seems like there is so much more opportunity to screw it up. If I screw up one of the other options, I could always go to option 4. Also, even though I am not doing a concours restoration, the Ames bracket just looked so different from original.

I am leaning toward option 1 based on feedback, but will still welcome other opinions.
 

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I used a variation of option 1. Open up the hole in the hole in the rusted mount until you have good solid metal then turn the washer to fit the hole. then grind or file until the washer just fits the hole. Chamfer both the washer and the mount, tack weld first and then fill the chamfered groove. Grind top flush and it will be good as new.
 

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Yes, that is the option I would offer. Find a hole saw, and cut to fit the washer, tack weld in, do the same with the hole in the washer. Grind to finish. Makes a nice looking repair.
 

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Discussion Starter #10
Thanks all. I am in the middle of the repair now. I basically chose option 1. I tried starting with a hole saw, but that really didn't work because the hole saw I bought didn't mount to my hole saw bit. Anyway, I used my dremel to cut out the old. I had to grind down the washer to make it fit and chamfered as Helmerrock said.

I had the luxury of being able to flip the frame over as it is stripped down now. I started with the underside and welded a bead around there. I then flipped the frame to the correct side and welded a bead on the top. I am in the process of grinding it down now. We will see how it turns out.

As someone on this forum said, "I may not be able to weld, but I can grind". I am not sure I am good at either, but I am learning.

I will post pictures when I am finished (if I am proud of the results :biggrin2: ).
 

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Hey Colorado, when you removed the bolts, did any of your weld nuts break loose inside the body? I had one, pass side second one from the back. Had to cut the bolt in half but am trying to figure out how to repair since I don't have a welder.....
 

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Discussion Starter #12
The two in the back under the trunk just behind the axle both were bad. I think those are the same ones you are talking about. My trunk was rusted enough that I just peeled back the metal and was able to get to it. I just ended up cutting it off and pulling the remains out from the top through the hole I peeled. The second one just pulled out of the mount because it was so rusted.

I broke off a couple in the front, but was able to slowly work through the rust and get them out. On one, I damaged the cage nut,but thankfully it is one I can get to to repair.

So long story short, I don't have any solution for getting to that nut, but I have to replace the trunk floor and the specific mount containing the cage nut, so I will repair mine when I replace the trunk pan. I definitely have to weld and I really don't see a way around it for you either. You may want to post to the forum specifically and see if someone else has an idea.
 

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The two in the back under the trunk just behind the axle both were bad. I think those are the same ones you are talking about.
Yeah, same ones. My trunk is great so I hate to cut it to get to that. I was thinking to do a 1" hole saw, get it welded, and then just use a body plug. I think it hides under the spare anyway. I'll ask the guy who does the body work how much trouble it is to cut a hole, weld it, then patch the hole...

Thanks
 

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Discussion Starter #14
Just to wrap up this thread, I am posting the after pictures of my repair. They aren't the best, but the best I could do with my limited welding experience and a cheap arc welder.
 

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Dan, no the welding doesn't look that pretty, but that floor is. Is that your shop/garage floor? Seriously, looks like some good work. Matt
 

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Discussion Starter #16
Yep, that is my garage floor. The previous house owner definitely had good taste and the garage was a big selling point for me.
 
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