How hard is it to weld thin sheetmetal?

[Lanse]

Hey yall...

Well, yesterday, I was approached by someone who heard that I do some welding and he wants me to help him fix the rust on his truck. Its a mid 90s F150, and the bed sides are rotted away.

He has bought some new 2x2 patch sections that are a perfect match, and just needs someone to weld them in.

To be clear, Ive never done anything auto-body, although I have played around with some thin (18-20 ga) sheet with my mig. I have no problem with turning this down if the general consensus here is to do that, Im just asking for advice here.

Im assuming that I would lay the new panels over the old, clamp them down, and go along the outside with a permanent marker, then remove the new panels and bust out the angle grinder with some cutoff wheels, and remove the old sections.

Then, Id just set the new panels in, turn down the mig (way down) and weld them in short sections (like a million little tack welds), and let them cool to prevent warping.

Once its all welded out, id hit it with a course flap disc to grind down the bead, and then a fine flap disc to smooth it all out.

My main questions:

1)How hard will this be? Anything else I should do, besides unhook the battery? Anything you can tell me to prevent warpage would be great... I guess I just tack in random places, FAR APART.

2)Anything else that I should know? Just wondering. Thanks everyone.

 

[Deere Scotty]

It can be real difficult. I personally havent done it; but I have watched people do it, & I witnessed the metal just melt away in some cases. The welder said the metal was too thin to do the job properly. It also warped the existing metal on the vehicle, & bubbled it a little.

 

[Fullthrottle]

I have welded in patch panels on my old cars, it's sure takes alot of time to prep and no matter how hard you try it gets some warping. Its possible to shrink the metal with the torch when it does warp, but it's a science. LOL That said it's not impossible by any means. If you still have some S-10 laying around cut out a chunk of sheet metal and try welding a couple pieces together. You can do it, but a little practice goes a long way and it is VERY time consuming. Hope you get to feeling better.

 

[Mark-Ia]

Google "Welding Body Panel Video" very informative. You can do it...

 

[Puddles]

If I were you, I'd do a search on youtube, seeing is believing. I heard ESAB makes a wire just for this application, supposedly easier to grind.

 

[Lanse]

THATS what I'll do!! I still have the hood from that stupid thing, i tried to sell it on craigslist and no one wanted it, so I decided to scrap it. And its sitting out in the barn. Thanks man!!

 

[Anonymous-0]

Easer to get a date with that 5'10" blue eyed blond you go to school with.

 

[Lanse]

Another thing, what should I charge for this? Im going to have to cut out the old panels, get everything clean, weld it all in, and grind it down.

How should I price this? Thanks everyone, you guys are the best.

 

[bison]

takes a lot of practise to do it right.
Any thinner patches in the metal or bigger gaps is gonne give lots of trouble to fill it in.

i vote to take the date with the blond too.

 

[Fullthrottle]

When I started working for myself this was THE hardest part of being on my own. Decideing what to charge. Usually you'll end up lowballing yourself. "And then" Some folks won't be happy if you do it for free, some folks won't complain if you charge too much, but won't come back either, but they will come back until your broke if you don't charge enough. Really only you know what it's worth, figure your materials and upkeep on your equipment,then a little money for your profit. Grandpa told me "Take what you think it's worth and double it, then it'll probably be about half of what it costs you to do it." Good Luck!!!

 

[Puddles]

No, no, no, stay away from girls, girls are bad. The one I have has cost me a fortune over the years! :lol:

 

[Lanse]

Lol, thats what im trying to figure out. Most of its labor.

Like they say, the best way to make a small fortune welding, is to start with a large fortune and open up a welding shop

 

[Fullthrottle]

Puddles, when did you apprentice with girls, graduate from school, go professional? I can't help the young gentleman with girls (women) I am good at lots of things (according to me) but even I know that I'm a failure with girls. SO... gotta keep trying!!! Sorry to muddle up you post Lanse.

 

[Anonymous-0]

Probably want to use .023 wire and you you don't have to turn it down that much. it has to be turned down but you still want to get complete fusion. Practice on some other old autoboy parts first. You want to use a series of tacks instead of continuous beads. Tack it all around and then alter your tacks so one area doesn't get too hot. After it's done you can use a hammer and dolly to help straighten it. There should be some good video's on the net of how to do it.

 

[Anonymous-0]

Have to see how it turns out before you can put a set price on it and how long it takes. Obviously if it turns out really good, you can charge more. Just make sure the guy is willing to pay before you start on it. I'd guess anywhere from $50 to $100 without seeing it.

 

[TimV]

Lanse: I've done a bit of body work, though I am far from being an expert, or even a talented amateur! However, I can pass on a few things I've learned. First, use 0.023" wire. That little MIG you have is perfectly adequate for body work, just change out the guide rolls (or turn them over--you'll have to check your machine to see how it's done), change your tip to an 0.023" one, change your wire and you'll be good to go. Make sure to cut all the way back to good metal--if you try to patch over rusty metal (and even if it looks good on the front it might well be rusted on the back!) you'll drive yourself bonkers with burn-through. Start your tack on the flat and move to the edge of the patch--the weld will "flow" onto the edge and make a nice smooth weld with less chance of burn-through. Speaking of tack, most patches have an edge turned up on them so that the edge of the repair panel fits behind the good metal and they're then tacked in. You can buy a set of pliers to turn the edge for under $20, which should work fine for a small job. One way of helping prevent warpage is using a damp sponge to cool the metal--tack a spot, sponge it, tack another, sponge it, etc. Body work is a nitpicker's nightmare--no matter how well you do it, you'll see things that aren't right, and when you think you got it perfect and move your head to another angle, things will stick out like a sore thumb all over again! If your friend is a perfectionist, walk away--your first job is going to look terrible no matter how hard you try. That's nothing against you--if it didn't, you'd be the first person in the history of body work that managed it, so the odds ain't in your favor! If you know that going in, and your friend is more interested in prolonging the life of his vehicle by patching small rust spots before they become big rust spots, then have at it--body work is a VERY handy skill, and ALWAYS in demand, and a GOOD body-and-fender guy can always find work. Learning body work, like any worthwhile trade, is a LONG, INVOLVED process, but you have enough skills to at least take a stab at it, and if you're willing to see the job through it should be better than what he has now. As was mentioned, practice on scrap first, and see how you do. There's a forum right here on YT that has a lot of tractor-related body work--read through the archives there and you'll pick up a lot of useful tips as well--there's not much difference between tractor sheet metal and car sheet metal, and most of the techniques are identical.

 

[Mike M]

Auto metal is REALLY thin !

Many of the body shops now prep the area,cut out bad,sand good down to bare then they use an epoxy glue and glue the repair panel in place using sheetmetal screw or pop rivets to hold it until it sets. Then grind down the screws or rivets and then start in with the filler to smooth it all out.
Many of the panels on new cars and trucks are now glued from the factory and very little spot welds used.

 

[molinebob]

Biggest thing with welding on a body of a truck is to not lay a big bead, you basically have to spot weld the whole thing in in many many spots, then grind down and bondo it smooth prime and paint. Slow and tedious work, been there done it many times..but well worth the hassle, i had someone put new wheel wells on a 85 dodge 4x4, two years later the glue was seperating so i sold it. Bob

 

[wilder11354]

get the complete replacement side panel, take bed off truck, drill all factory spot welds that hold that side panel on, look good there in behind tailights, under floor pan drop seam, tire arch, etc, etc,, but don't go completely thru, take whole side off, install new side panel, clamp it in with many, many clamps, drill 5/16 holes in new panel in the same approximate locations as old outer panel, and weld in the drill holes in new panel to old panels under it and its done. should be able to get old side panel off bed in about 3 hours after it removed from truck frame. good 8 hours it should be ready for paint.

 

[GordoSD]

Back in the day, in sturdy sheet metal, like 57 Chevy, we did what was called
"hammer welding" Google it up and see what you find.

 

[ShadetreeRet]

Check out: eastwood.com They specialize in tools for auto body repair and restoration. They sell a flanging tool which, once you cut out the bad spot, creates a step in which you lay the patch panel and when welded in it is almost flush with the existing metal. They also sell what they call a "stitch welder", specially designed for welding thin sheet metal, it connects to your welders existing cables. I purchased one a few months ago, but my project had to be put on the back burner, so I haven't used it yet.

 

[trucker 40]

The best way to put a patch panel in is to use those pliers like Eastwood sells that make a flange and then you lay the new piece in where the flange is and tack it like you said.If you try and cut it right where it is end to end it will warp all over the place..023 is the best choice of wire and I use .030 tip and it works better for me since it doesnt stick the wire as bad.Making all those tacks its kind of easy to get a burn back on your wire and then ruin a tip with wire stuck in it.Also with the bigger tip it will unhang by itsself a lot of times.You may as well try and see what you think.Its a lot harder than welding thick metal.
Dont glue it on or pop rivet it.Thats possible but you have to be good at using body putty which is harder to get right than welding the panel in.For somebody who doesnt have a welder or doesnt want to weld or learn how to weld you can glue and rivet stuff,but it can be welded.The same as anything else you ever do,the more practice you get at it,the better off you will be doing it. Just so you know its not easy.You have to hammer out the dents if it warps and that is an art its self.Somebody who knows how can hit it a few times and it will be perfect.Somebody that doesnt know what they are doing can make it worse than it was.Maybe look on the internet,or if its not a lot of trouble for you to go to a library,go and take out a book on auto body repair and read it.Then if you have questions you have a better understanding of whats going on and can ask so you can get help.
They make it look easy in the videos like on You tube,but its not near as easy as they make it look.Its a whole lot more than just welding the metal,its actually working the metal into the shape you want it.

 

[trucker 40]

Well,maybe until you get good at stuff like that,charge some rate that kind of reflects what you did.So say figure about 12 dollars an hour.If it looks real good say 15 dollars an hour.He wont get any shop to weld anything for 15 dollars an hour and if you are good and get more business,raise your rates!
Shops charge like 50 or 60 an hour,some more than that.But they probably know what they are doing and have all the tools they need and plenty of help.Their work looks good when they get done.If it looks bad,takes you a few days,and you are lost at what you are doing,maybe just 50 or 100 dollars.

 

[msb]

Get a flange tool and glue the patches in. Don't even try to weld them.

 

[Bodyman]

Lanse, to answer your question, it gets easier with practice, LOTS of practice. I think your idea of practicing on your old hood is a good one. If I may, I would also suggest you invest in a flanging tool, either pneumatic or manual, there are many types. It will make this project and many in the future easier and more cost effective for you and your customer. Cut two pieces approx 5 inches by 10 inches, flange only one of these pieces on the 10 inch length. That flanged edge will represent the truck box cut out for the repair panel, lay the other piece you cut with a 10 inch edge lying in the recess of the flange you just made, allow a gap of 1/16 between the flange and your other unflanged piece that represents the patch panel. As others have said .023 is the choice of wire size. Clamp the two pieces in a few places keeping them flat and tight together, put a spot weld at approx every half inch, giving a minute or so between welds (for cooling, resist the temptation to cold quench for the sake of a few minutes, that"s another lesson for another day) to control warpage. If your spot welds don"t lay nearly flush with the edge between the two parts it is time to make adjustments to you heat settings after the first couple, not when the full length has been welded. If all is well at this point, let it cool till all heat has disapaited. Then come back to fill the remaining gaps. If your machine has a stitch setting use it now. Start at one end and weld about 1/4 inch of the 1/2 inch gap we left earlier. Take your time, after the first weld move down to approx the center and then to the other end. By moving these welds and patience moving to the next one with this lighter wire warpage should be kept to a minimum and your overall job should go better and quicker in the end. At this point grinding and thereby warpage should be very minor. As to cost, it is all relevent to cost of materials and supplies and lastly your expertise. In my area hourly rate is from $55-$85. (some difference from the $11 hourly rate when I first went into the trade.) That being said, when I first began learning what this was all about I did work for friends and neighbors for little and no labor, just some money for parts and supplies. I am sending a couple of pics from one of my projects where I got tired of high priced repair panels "DID NOT" fit so I made my own and installed them pretty much as I described with minamal grinding. So if this got too long I am sorry but hope this helps.

 

[Duner Wi]

Listen to Martinsr.
http://autobodystore.com/forum/showthread.php?20610-flange-or-lap-joints

 

[Inno]

All good advice........well most of it.
I did a cab corner and wheel arches on my '98 Chevy over the winter. I installed the cab corner with Fusor 2 part epoxy. I welded in the wheel arches with a 135 Hobart mig. The biggest problem I had was warping when I welded. I spot welded, went slow and jumped around so as not to over heat the metal but I still got quite a bit of warping. Whether you weld or glue you will still have to use body filler. It is much easier to fill/smooth non warped metal! If you can clamp it properly, I would recommend the epoxy.

 

[scotc]

The MOPAR magazines say to set the heat for the metal thickness, then go around the panel about every inch to inch and a half, and spot weld it in, and just keep going around it spot welding it. Once you have the panel in, do any grinding and sanding needed. It's not that hard, but very time consuming.

 

[Anonymous-0]

I wrote a big thing and it won't take it because I am not a member anymore. You can make a paper mache to spread around the area to control warpage. Just water and newspaper. TM 9-450 Metal Body Repair and Related operations is how I learned to patch rusted cars. Check ebay.Make the vice grips to flange panels yourself. Clecos too.

 

[Chester]

Check out this work............

[/url]http://www.garagejournal.com/forum/showthread.php?t=81325[/url]

Scroll down to post #7 to see a master's work.

 

[Inno]

(quoted from post at 10:53:20 06/22/11)
Check out this work............

http://www.garagejournal.com/forum/showthread.php?t=81325

Scroll down to post #7 to see a master's work.

That is a great site, that thread has some amazing work! I had to sign up. Thanks for posting that link.

 

[Chester]

(quoted from post at 12:01:20 06/22/11)

(quoted from post at 10:53:20 06/22/11)
Check out this work............

http://www.garagejournal.com/forum/showthread.php?t=81325

Scroll down to post #7 to see a master's work.

That is a great site, that thread has some amazing work! I had to sign up. Thanks for posting that link.

There is more...........This is the one I was actually looking for:

http://www.garagejournal.com/forum/showthread.php?t=53534

(figured out how to make it a direct link this time)