My crack has grown.

Are there any recommended methods of repairing this other than just having it mig welded?

 

THAT'S a great example of a CRACK! Being a rookie, I can't give you a good answer......I wasn't paying attention--What size engine does the car have?

 

i would be looking everywhere for some compelling reason it cracked like that. it will take some welding and probably a plate over it. have you considered a different frame ?

 

And people worry about the welds cracking.

 

Any competent welder can fix that. I had a crack where the lower A-arm bar bolts to the frame. I welded the crack in with 38,000 psi rod, then ground the weld flat, welded a fitted plate over the area so it would not happen again.

I did the other side with an identical plate so it would not have the same problem in the future.

The chevy power book has diagrams of where to gusset our frame so it will be stronger or you can buy the you weld it kit.

 

WOW
Now that's a crack! If that's behind the the spring towards the middle of the car, I would have a professional do the welding and definitely have it re enforced. If it's in front, towards the bumper, I would clean it, bevel it and mig weld it. Let it cool slowly.

The steel looks very brittle and I've never seen one crack all the way around. Sometimes too muck heat will make the steel around the edge of the weld brittle but not the entire frame rail!!!

 

It is on the back side of the spring on the drivers side.

I am amazed at how crappy the weld are from the factory back then.

That still looks repairable, right??

 

That is very fixable. I would make sure to drill a hole where the crack terminates to keep it from growing.

Weld it up, add a reinforcing piece of steel. Make sure to anti rust treat the weld. Pot 15 or something similar.

 

It most likely started next to the weld in the heat affected zone (HAZ), once a crack has started it will only continue to get worse in many cases, and will never get better in any cases. I would most certainly repair it before I even remotely considered replacing the frame if the crack is the only issue with the frame. First you will need Good access to ALL of the crack. Second and the most important thing is you will need a good welder to do the welding. This is important!, this should be a thru wall repair, i.e. both edges of the crack should be beveled to allow a full penetration weld. Mig welding will be fine, now some may take exception here but I would stay away from flux core for this repair. If at all possible my preference here would be to TIG weld this. But if not possible Mig with a gas cover shield will be fine. Preheat is not needed if above 50 degrees. Post heat after welding wouldn't hurt if it was mig welded but not absolutely a have to thing. Tig welding is slow enough that it tends to anneal itself while welding, so no post heat is really needed. If you would like to question me for any more detail feel free to PM me for additional help.

 

Here's mine...

 

i wonder if a spreader bar would prevent this type of thing. it would seem that removing or minimizing flex in that area would have to help.

 

Agree with it all including the flux core. Tig would be your best bet but most likely the welder will Mig it. If you weld a plate over it for strength it leaves an area between for rust to start. Like a pinch weld on a body panel that isn't treated.

 

BFI and Indiancreek, thanks for the good info.

Two main questions:

1) If I find a crack in the frame of my C3 (I inspect it every month) how do I find a good welder to fix it ( I.e. what questions do I ask)

2) So a patch plate over a repair is not necessarily a good idea?

I will gladly read any information source you recommend.

 

Wow! how do you find a good welder. First thing is they do not have to be a "certified welder" to be a good welder! There are far less good welders than there are welders that say they are good welders. Second thing is don't insult anyone about their abilities, but this is your car frame that we are trying to do a proper repair on so it's your right to question how they intend to do the repair. I have outlined how I would do the repair, anything that does not very closely follow what I have explained would be suspect in my mind. I would ask them what kind of experience they have, how do they intend to do the repair. What welding process do they intend to use? Ask to see some of their work if possible. What I have outlined for you is based on my experience in the welding field. I have been a certified welder in multiple processes for 40 plus years, SMAW (stick), GTAW (tig), GMAW (mig). I have worked in a race shop, fabricating circle track chassis as well as a general welding shop that worked on whatever came thru the door. Remember my first comment though "they do not have to be a "certified welder" to be a good welder!" What kind of experience do they have? My repair plan is based on real world experience. There are a lot of good welders out there and there are some that will be close to you with a little looking.

 

How much would you expect a repair like this to cost? Just looking for a range so I know I'm not getting gouged.

 

I suggest a frame shop. I had a repair done in mine about 15 years ago at State Frame in Ontario, CA. They have been around forever and will make sure your frame is straight and aligned when done. Was a father son operation but the Dad would be fairly old by now. Not that far from you for a top quality job. I think I paid about $300 for everything and I had 2 cracks at the front end,

 

just be sure if your welding it to put a valley in the weld
take like a 1/4" think grinding wheel and cut into it and fill that. dont just fill on top.
then of course plate over if you feel the need. done a lot of repair on off road truck frames coming back from races and never had an issue once theyve been fixed

 

also, if your checking for cracks. be sure to look around the cross member right in front of the engine and around the motor mounts. we had a few good ones there. that area sees a lot of stress from cornering and the engine

and i agree with BFI on his statemen regarding a "certified welder" and a "good welder"

 

My welder is a crusty old retired guy who can't stay retired.

In other words, he closed his welding shop, but is there everyday working on projects

So now guys just hang out there and work on cars. If you are a nice guy he'll gladly weld stuff up for you.

I'm not saying that with age comes experience, but on a frame I believe I'd try to find someone tested over time.

Fortunately, the frame is really good, and easy, steel to weld. No fancy alloy or weird composite. Good old steel. So a Mig or Tig should work fine.

The plate probably isn't "necessary", but would give me a little piece of mind. Comments about rust are justified. I always try to rust proof them before painting.

All the suggestions about prepping the crack are correct. Grind a valley in the weld, drill on either end of the crack, and make sure your weld is deep enough.

This type of weld really isn't rocket science, but it is in a bit of a tricky spot.

 

You can reach out to the iron workers union in your area or a vohtech school. Many have students learning the trade and you have the perfect test bed for them to learn on. A frame builder for race cars might do it but these guys are scared to death of liability!
I found that some will do it for cash with no receipt.