Technical How easy is it to mig weld patch panels

Hey folks I have a 56 Buick Century rocker panel on one side has a couple of holes I didn't sand it down to bare metal and suprise to me it did have good solid metal I just bought a might welder set up and got an old door... Also I bought a patch panel from Schofield. what you think folks. practice on the old door or let the body shop do it thanks. .

 

Practice practice practice. Also buy a good grinder!

 

Practice on the old door, never learn by farming out the work! ( you can always farm it out later if you don't get good results)

 

Get the body shop to do it.

Unless you want to learn how it is done. In that case practice, and mess up a few old doors and fender learning.

Some tips. Spend time making the patch fit perfect. The patch has to fit tight like the skin on a g****. If there are any gaps you can push it down and weld it but it will warp.

Tack with long tacks and skip around. Don't put too much heat on all at once.

You need more heat, less wire. Most guys have too much wire and not enough heat and make gobby welds with poor penetration. When you get good you can use heat and wire, and lay it down so fast the metal doesn't get a chance to heat up and warp.

Take your time and pay attention to what you are doing and what the metal is doing. It's not that hard once you learn how but, expect to mess up the first few attempts.

 

thanks

 

I suspect that there is more rust damage there than your eye can see. As suggested you should practice welding and trying to control the weld shrinkage . Bill

 

Before you can get a good Mig weld on the front side of the Holes you must get the rust off the back side of them. How do ya do that?
The Wizzard

 

thank you

 

thanks Bill

 

you do that by cutting out the rusty metal, until you get to solid metal. Don't be surprised if you have to go a lot further than you expected.

 

OK...I would like to learn thanks

 

I just Chuckle often over this kind of stuff. One thing I've learned is it's never just a pin hole.
The Wizzard

 

When you get to good metal and have a patch panel ready, practice on the same thickness material. Spot weld a few inches from spot to spot and allow the metal to cool off before welding a spot next to another one. Grinding the welds correctly is also VERY important - control the heat or the panel will warp. Take your time.

 

A couple of guys have eluded to this: the rust starts on the inside. You will find more than you now see. I just did the rockers on my '33. Drilled the spot welds and removed the complete rocker. Trimmed up the new one and spot welded it on.

 

Look at it this way- there's a learning curve to anything. Once it's mastered nobody can take it away. Now for some serious perspective, at one time in your life you were afraid and not quite sure how to use the toilet. Someone helped you get it figured out.

 

Practice till you are comfortable, then go for it. It's a rocker panel, and they are much easier to repair than a door or quarter panel. Maybe you have some exhaust repairs to practice on.

 

Thanks 55 I'm going to practice on some doors I have here

 

I am no expert but a couple things I notice when I do this type of stuff. First is bare rust free metal is essential on both the part being welded in and the area on the car it is being welded to. Second is the correct mix of gas in the mig welder for what you are doing. Third is the correct size wire for what you are doing. Next is to cut the patch panel so it fits as close as possible to the opening it is being welded into. A 1/16th inch gap seems to work pretty well for me. Nothing worse than trying to hang weld in a big gap! As the others have noted above get some metal of the same thickness as the patch and then do a bunch of practice runs on it. Jump around running small beads of 1/2" or so on **** welds. When you get that down so that you can do it without warping or blowing through the panel then you can move on to the real thing. Good Luck!

 

I learned after practice and more practice. Take your time. When grinding use the edge of th ewheel and knock the high part of the excess welds off. Easy does it!

 

This is absolutely correct. You can't just fill the holes, you'll chase them, and there is more rot then you think.

This is fantastic advice, and I've never heard it put in such a basically relatable way. Cheers @31Vicky with a hemi .

Good advice as well. Comfortable is important. In position and ability. When you are starting, do many test pieces to get your comfortability in ability up. Then, when you think you have the ability, make sure, you are comfortable in position to do your weld. If you are new to welding, and in an awkward position, your weld won't be good. Your weld might not even be good if you have some time under your belt, but still aren't in a comfortable welding position. "If you can't weld good, weld a lot" Do a lot of welding, then take care of your patch.

Once again, good advice. Clean metal is key. Gas and wire size is important as well. But most important is fit. A large gap to weld will always turn out worse then a nice fit. Fit is key. If you are going to take time on anything, take time on fit. No matter what type of welding, fit is key.

Obviously practice is important, but I absolutely disagree with the edge of wheel advice. I think that this is one of the most common mistakes. Using the edge causes gouges. When you are starting, use the sanding disc as flat as possible. In fact, that is my advice for experienced people as well. There are reasons to use the edge, but you need to be experienced on order to know when. Keep the disc flat, otherwise you will never get a flat panel. It takes longer, but very beneficial.

 

From my experience of almost 50 years of patching rust everything in the picture needs to be ground out to get to solid metal . Then treat what is left and then make your patches . Treat both sides and the rocker panel with weld through primer, Available at your local NAPA store. Take your time to fit your panels and weld in and skip around to avoid warping the metal. I like .023 wire for patches ,but have used .030 wire.
The rust behind the original metal will pop in your repair if you don't get it out and treat the metal if you want a long lasting repair.
I just finished a car that had fresh paint over duck tape and bondo. The customer had not even driven the car before it started to pop. Ended up spending a month cutting out and grinding off fresh paint to get rid of a bad job that the customer paid 5k to have done.

 

You can also check-out the good info on this older post:

**** welding made easy! The H.A.M.B.#post-8417153.url

 

There probably needs a better explanation expansion on edge grinding.

With a straight grinder/ cut off too and a 3" disc the edge of the wheel on the proud weld with care and precise guidance grinding only on the weld. The shaft of the grinder should alway remain parallel with the weld and the wheel perpendicular. The only metal removed or even touched is the weld. There's also very little heat from this process. It generally takes a bit longer to grind this way but it's far easier to finish.

 

With that many small holes I would put full rocker panels on , they rot from the inside , more holes will likely appear later..


Sent from my iPhone using The H.A.M.B. mobile app

 

Hey guys thanks thanks again for your love... I have all my emblems (trunk emblem, bumpers, jet tray; headlight have been rechromed; hunted them down..... My dad will be 93 in July and he sad to REPLACE THE WHOLE PANEL SINCE I HAVE IT

 

Obviously practice is important, but I absolutely disagree with the edge of wheel advice. I think that this is one of the most common mistakes. Using the edge causes gouges. When you are starting, use the sanding disc as flat as possible. In fact, that is my advice for experienced people as well. There are reasons to use the edge, but you need to be experienced on order to know when. Keep the disc flat, otherwise you will never get a flat panel. It takes longer, but very beneficial.[/QUOTE]

Well perhaps I should have stated that after the proud part of the weld is almost flat then go back and gingerly grind it flat to the surrounding metal. I prefer a cut off wheel for this. Using a grinder on the horizontal plane to grind all of the weld down is a very good way to get an "oops!" followed but a lot of cussing. Using the disc on the vertical plane allows the person to see what they are doing much better for the initial work. See what 31Vicky has to say.

 

I forgot to include the method I use.
Personally, I'm not a fan of the grind the weld down with the edge of the cutoff wheel thing. There is nothing wrong with it, just not the method I prefer.

You don't want to introduce too much heat into your panel, so with MIG I will do a series of tacks. But MIG is a high fill process, so your tacks will be kind of proud of the parent material, and that can mean that by the time you are getting to the point where your tacks start connecting to make full welds, you're welding to those proud tacks and when you sand those sections will be thin because there wasn't adequate penetration.
And as stated above you can also introduce too much heat with sanding your welds. So what I like to do is do one series of tacks, let it cool, then sand each tack down until its almost down to the parent metal, then do another series of tacks, etc. until the weld is complete. Then once the weld is complete, your whole weld is almost already sanded down, so no need for the cutoff wheel method, and you won't have thin spots where your tacks connected.

When you are practicing, try both methods, and use the one that works better for you.

 

Well that is what I do as well actually. I find it also avoids voids you may not see if you weld, weld, weld before taking the welds down. But I do use my cut off wheel as I stated.

 

I think ******s point with using the edge of the wheel is in inexperienced hands you are far more likely to go too deep or slide off the weld into the surrounding metal cause further damage than you are by using a flat disc especially if you are using a super thin grinding wheel.

Sent from my HTC One_M8 using The H.A.M.B. mobile app

 

I did so much rust repair and grinding that the shavings from my clothes turned to giant rust balls in the drain on my washing machine and clogged the tube and flooded the garage

here is what I have learned in the process. most patch panels ****. the best thing to do is get a good piece off another car. I met a guy at the junkyard cutting pieces from a Sunbeam Alpine, next thing you know I was patching his rusty car at my shop. later I did some other cars where store bought chinese parts were just totally wrong. had a guy buy a fender piece for a F-100 when all he needed was a little patch at the bottom I made from flat sheet. there may be some good ones out there but I have not come across them.

heat is the enemy. both in welding and grinding. have something else to do while welding so you can let the welds cool before welding near the same spot. GRIND USING THE SIDE OF A GRINDING DISC. don't listen to anyone that says otherwise. I use 2" cut off wheels on my air grinder, and grind ONLY THE WELD, not the good surrounding metal. I know a guy who chopped an F-1 pickup, he liked those flap wheel type discs on a 4" grinder. he ground until the weld was totally gone and the panel was paper thin and full of pinholes! sheet metal is thin enough already.

as stated, what you see before you start is just the tip of the iceberg. did a '72 Chevy Suburban where there were rust and bubbles in the paint. didn't look too bad from the outside. I ended up replacing pretty much the entire bottom 6" of the truck all the way around, as well as much of the wheel openings in the rear. he had more in rust repair than it was worth and I work cheap since I had no overhead costs and am slow as hell.

probably the most important thing here is that paying someone else to do it is no guarantee that it will be a good repair. I had a friend with a 66 (?) Lamborgini 400 GT.. a beautiful car, . worth a big bunch of money. he had it forever and it was rusted to ****, he had money and took it to a high end resto shop and had it all done. couple years later there was rust bubbles in the big dollar paint job.

I say do it yourself. it is fun until you get sick of it like i did.