Frame Rail repair "cap"

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J

J Glenn

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The caps are meant to go over rusted frame rails. These are just a band aid fix. I wouldn"t waste my time or money. Replace the frame rail is the only correct way of doing it. This is like welding a new quarter skin over the top of a rusty quarter panel!
 
I used some on a camaro a few years ago. The metal is thicker than the OE sheet metal. Like 3 times thicker. My welding skills weren't good enough to weld those to thin OR metal. I had a buddy do it. They're cheap enough and work just fine but I won't personally use them again.
 
Caps are just a band aid. The original frame rail will keep on rusting, and the cap will start rusting because of the trapped rust.

You had the right idea the first time. If the rust is confined to a few sections, you can cut them out and patch the rail. Just keep in mind that once you start cutting and grinding the patch will probably end up being twice as big as you think it needs to be.

If you have more than a section or two that's rusted, it's probably worth replacing the whole rail.
 
72bluNblu said:
Caps are just a band aid. The original frame rail will keep on rusting, and the cap will start rusting because of the trapped rust.

You had the right idea the first time. If the rust is confined to a few sections, you can cut them out and patch the rail. Just keep in mind that once you start cutting and grinding the patch will probably end up being twice as big as you think it needs to be.

If you have more than a section or two that's rusted, it's probably worth replacing the whole rail.
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MY frame ad a crack in it around one of the K frame holes, I welded t up, ground it flat, and made a frame cap for that area, and a matching for the other side. Then put front support bars in the engine bay, along w/ a 6 point cage. Pretty stiff for a streetcar.
 
A lot of Classic parts are just reboxed from others. Check around for better pricing. I agree with most- band aid fix BUT if this is all you have then it’s all you have. Just cut out the rot first to good metal. It will spread under the cap if you don’t cut it off before hand.

Good luck with your decision and don’t forget to post pictures- it may end up in the help section.

Joe
 
I used one of those on my Duster, the one I used were made by safety-cap.
It did not fit worth a crap, I actually had to split it in the bends to match the contour of the frame rail.
 
famous bob said:
MY frame ad a crack in it around one of the K frame holes, I welded t up, ground it flat, and made a frame cap for that area, and a matching for the other side. Then put front support bars in the engine bay, along w/ a 6 point cage. Pretty stiff for a streetcar.
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They can work well as a gusset. But for their intended use of rust repair they’re not a good idea.

And like anything they depend on the prep. If you remove all the rust and paint everything with an etching primer or weld through primer it’s a different story. It also depends on how well you fit them. But adding layers over weakened rusty metal is a temporary fix at best.
 
72bluNblu said:
They can work well as a gusset. But for their intended use of rust repair they’re not a good idea.

And like anything they depend on the prep. If you remove all the rust and paint everything with an etching primer or weld through primer it’s a different story. It also depends on how well you fit them. But adding layers over weakened rusty metal is a temporary fix at best.
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If ur referring to my repair, did u miss the "weld it up first" repair before the home made caps? no rust involved, was a stress crack, car used to be a raced before I got it.
 
I would much prefer to see a welded replacement even if it's hand fabricated rather than seeing a cap on a car. The bandaid comment is dead on. If you leave rust in place, regardless of the "top dressing", it will continue to eat the parts.
 
famous bob said:
If ur referring to my repair, did u miss the "weld it up first" repair before the home made caps? no rust involved, was a stress crack, car used to be a raced before I got it.
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Nope, didn't miss it. I said they could be useful as gussets if they're installed over clean metal. That's what you did isn't it?

I just wanted to reiterate that when used for their intended purpose of rust repair, they're not a good idea.
 
72bluNblu said:
Nope, didn't miss it. I said they could be useful as gussets if they're installed over clean metal. That's what you did isn't it?

I just wanted to reiterate that when used for their intended purpose of rust repair, they're not a good idea.
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No rust , gotcha.
 
I bought a set that included the shock tower part and the a-arm tabs. Very well made, fit well, installed by a pro.
They were not caps, I don't recall from where but I would imagine I discovered them here.
The rest of the frame rails were in excellent shape.
 
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I had to build mine from scratch for my 64. Using a cheap bender and some basic hand tools.
 
I believe it's 36 inch cheap Harbor Freight chinesium. I used 16 gauge for this which is really to heavy for this style bender but I used Map gas to help along.
 
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Yep I'm still working on her! Finally finished the Frame rail for the Passenger side just need to prep the car to weld it in. I'm getting better at making them for sure. I finished both quarter patch panels from Laysons and wheel house fabrication as well. Here is a pic.
 
68383GTS said:
The caps are meant to go over rusted frame rails. These are just a band aid fix. I wouldn"t waste my time or money. Replace the frame rail is the only correct way of doing it. This is like welding a new quarter skin over the top of a rusty quarter panel!
Click to expand...
In this case worse being suspension loaded. If theres enough points of solid weldedsecurity
probably better than stock at least

Ask me how I know.
 
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I have a car used as a pace car at a roundy round, turn left, dirt track for decades. The wet dirt caused just the lower part if the rear frame rail to rust, the sides were fine. Weird.
I fabed some heavy 10 ga sheet into "L" shaped pieces and welded er up! Solid as brick poop house! I know the 10 ga was over kill but it was the scape I scored.
No matter we are doing, the rust has to be cut out and go from there.
 
You will never regret doing it right, cut out the rust weld in new. Can you post a pic of the rusted area?

Nice work Seansmopar!
 
I'm still on it! After making the frame rails and part of the trunk floor section and fabricating the entire tie section that supports the frame rails to the trunk and the lower valance. Cutting myself, burning myself, getting metal in my eyes, ears and mouth i finally got it back together.
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