Ok guys here it goes. I am by far no a great sheet metal welder. I have been practicing, but seem to fall short of the magic settings. I have a lincoln weld pack 3200HD, yeah the home deep blow version. I have gas hook up and run the argon mix. I bought some .025 wolid wire today, and have been toying with the settings but jsut can not seem to find that magic setting. It is just regular ol sheet metal, mainly on some left over scraps, but I have some cracks to weld up on a jeep floor board, and on my model A body. I was thinking of trying the torch and brazing it, but I wanted to get you expert guys opinions. I am also looking for good grinding, sanding disks, pads, etc. what do you guys use to knock down welds. I have some 3m disks uhm twist lock style. I can not remember the real name for them right at this moment. just to list a few of the $25K in tools I have are as follows. Air die grinders with 1./4 inch arbors, air orbital sander, air disk sander, 4 inch angle grinders, 7 inch angle grinder, hand files(I prefer pneumatic stuff lol ) Cut off wheels, sawz all etc. I wish I had a plazma, but not until I move outta Corpus. unless someone has one they wanna trade or sell off cheap I also have a 7hp 60 gallon Ingresol Rand Compressor 220v. A 225 amp arc welder etc. Oxy/acet torches as well with cutting heads and brazing heads too. Right now I really want to learn some good techniques for welding sheet metal. mainly butt welds,(unless they arenot good Ideas on sheet metal) and welding cracks. I've got my thick metals down pretty well, but this thin stuff kills me. I am going through a couple of of other sheet metal working books I have, but they are mostly forming sheet metal, and tig welding, I can not afford a tig at this time. So any help from you guys would be greatly appreciated. Thanks way in advance. Will
For welding sheetmetal, you have to understand just how thin it is and how the heat and the way you weld it affects it. The thinner the metal is obviously the less heat it takes to burn it. You are gonna want to turn your heat down to maybe B and run the wire speed around 6 to start and see how that does. Leave the heat alone and play with the wire speed until you can get a clean weld that will stick. The way you weld has alot to do with it too. You want to start the arc on the thickest piece of sheetmetal and drag the puddle onto the thinner. I usually jump around on areas sop as not too warp. This also cuts down on burning through. When the weld itself or the metal is too hot it can easily just melt right off. If the weld is still cherry red and you try to hit it again it will surely burn. Small, quick tacks are the way to go here, don't try to run a long bead like on thick stuff.
Try setting the Lincoln on highest setting....try to get the two panels fitted with as little gap as humanly possible...this is mandatory... Then spot it-[just a split second and let off the trigger]VERY IMPORTANT.... -you'll have to experiment with wire speed as the more heat will require more wire. You want as little "build" as possible...just a hot spot weld that touches BOTH edges... NO welds should done as a "bead"-not even a 1/4" long,this is too much heat in the work... I space it a couple inches and jump around all over -this keeps the panel as cool as possible. it takes a lot of time this way -but mostlikely you'll end up with very little warpage, after all these "spots" are connected with no gaps.......these are very strong and if you'l look the spots are about equally sized on both sides of the panels,[not just on one side and nothing on the other]...if so add MORE heat. A good rule of thumb is to feel the work as you go and if it is very hot at all stop or move around to allow cooling.... NO BLUE METAL.
second Lil tip.... #1 weld blows thru=let off trigger faster/OR too much heat/OR too little wire OR wide gaps #2 tall bead=too little heat and/or too much wire
Hey, For welding sheetmetal it's kinda hard to beat an oxy/acetylene weld. The welded beads can be forged (sucessfully) and usually most thicknesses can be welded without much problem. A squirt- gun weld will offer ya speed, but isn't always a great way to go. Spend the time now to learn to gas weld and you won't regret it. You can grind welds with the edge of a cutoff disc, but always! always! wear a face shield. Surgery, for facial cuts, and eye surgery, is very painfull and expensive. Swankey Devils C.C.
Thanks for the tips guys I am fixing to head back out side to mess with it some more. I was running B heat and about 2.75 to 3 on the speed. At least thats where it seemed best to me, BUT I did burn througha few spots onthe crack. I was using the 3m lock disks to prep the surface, nice in clean. but the damn welds seem to be huge. Well huge for sheet metal. I will ceertainly bump the heat a bit, and speed as well and do fast hot spot welds moving from area to area. Should the Temp or touch feel come from bare hand or with a glove. I know that sounds kinda stupid, but if I am trying to keep it as cool as possible I would ASSuME that it would be with my bare hand. Oh and I know not to touch a cherry red weld. lol just thought I would throw that in there. Thanks again Will
I know how to gas weld, but I am a bit rusty on it. I used to weld it alot back when I was younger. I learned stick and gas at about 9 yrs old, repairing my go kart motor mount and broken frame. Then I just started grabbing anything metal cleaning it up and welding all kinds of crap together, some times even just trying to get smooth even beads with the arc welder.I will check my tanks and make sure they are full, and pick up some rod/flux etc this week. Is there a certain brand of rod/flux you guys prefer?
Well I have this nice set of Mechanix Gloaves that are covered in oil. I base my heatness on when I touch the welded area if the gloves start to smoke or not. Definitely not the right way but my shizzle aint warped. I never said the bodywork was straight though.....
I have learned alot in the past few years about making sure the material is BAREEEE like a babies ass. I used to think I could crank the heat up and burn through the rought crap. I learned the hard way.
i run .30 in my home depot special right nowbut i like .35 better..wire speed at 3 ..anything higher splatters..i do not like .25 at all..it doesnt weld worth a shit to me anyway...try ti yopu may like it there....i run my welder on low heat...then on thicker metal i just turn up the heat and keep the wire at 3 and the psi at 20...works for me
Just some corrections. You can't hammer weld MIG welds. You don't need flux when gas welding steel. I wouldn't suggest brazing...it's just not necessary for the most part, weaker than welding, problems with getting filler to stick to it. Other than that...listen to Kenny (choprods).
I have different guage wire as well and will try those and the heat and speed as well. So when gas welding its just like doing mufflers etc no flux just good old mild steel? or like the good ol days coathangers? I dont think I want coat hanger holding my shee metal together though. Thanks for the advice guys.
You might want to try some of that wire called "Twenty gauge" made by Harris( I think). Its actually .030 gauge wire that is a type of flux core made just for sheet metal. I've used it and there is noticable difference.
Don't be hating on brazing. The strength of welding and brazing can far exceed the strength of the base metals themselves...so brazing can be plenty strong enough. There are some advantages to brazing thin material. Do a search on brazing vs welding on google if you're thinking about trying it.
I'm a new welder (meaning poor, not just starting) and have a similar machine. I've been welding floor pans also. On that rig, to weld 16 ga. to the existing floor good metal, I weld on B and about 2.5 speed. To fill holes or weld lesser quality existing metal, I've got to drop the heat to A and weld just around 2. I'm not using gas though, but acid core. And...my welds are ENORMOUS. Takes tons of grinding but it works and looks good at the end.
No, Twenty Guage (or Bullseye) is NOT flux core! It uses a powdered metal core to allow you to get into the "spray welding" range with low current machines and/or on sheetmetal. It is .030 wire, and works great.............but basic technique does still apply. I can't stand .023-.025 wire! Not even in a 110 MIG! Bump the heat up, and just do a series of tacks - skipping around so as not to heat any one area too much. .030 wire works much better for that. There was a tip in Ron Covell's Street Rodder mag column a while back, and for some odd reason, it works for me. Do a short series of tacks (or a really short bead), and go over it with a stainless steel wore brush until the weld is cool. I don't know why I tried it, but it really does minimize distortion when MIG welding sheetmetal. No, no coathangers. Where did that whole thing come from anyway? I've heard tons of stories about that...........always from someone "watching", never from anyone who has actually done any welding that way. Get some proper welding rod! Even TIG rod works well (ER-70S2 should be good), or RG-45 (?) gas welding rod. Failing that, use your MIG wire as filler! I bought a spool of .035 MIG wire just for gas welding sheetmetal to go with the .045 gas welding rod. I really prefer the "peacefulness" of gas welding versus the "violence" of MIG. Brazing is a great process - in its proper application. Brazing is not for butt joints or crack repair though. Its proper use is in overlapped joints where the brass rod works as a sort of "glue" to hold the pieces together. JD, you might try more heat and more wire speed and use the "series of tacks" method. It should burn the welds in a bit better and make them flatter. Just a thought..........and it works in my garage. My welding is done on the cheap too - Harbor Freight 110 MIG with flux core, Lincoln SP135 with gas and Bullseye wire, as well as Victor and Henrob torches for gas work. The HF was a gift, the Lincoln represents $12 in Raffle Tickets at a car show (with a full bottle of gas!), the Victor rig was $100 (plus the cost of the tanks) and I bought the Henrob (used once before I bought it) for $200. I still have to do my heavy welding elsewhere (I ain't welding my frame with a 110 MIG!), but light stuff and sheetmetal if fair game Practice, practice, practice................and when you think you've got it, practice a bit more I usually grab a couple of pieces of scrap to warm up on whenever I'm going to do some gas welding......or if I'm going to MIG something important and I haven't welding in the previous couple of days. HTH a bit. Tim D.
Don't feel bad 5window, butt welding sheet metal is hard to do even for the experienced guys. The big problem is getting impatient, in a hurry, and overheating, as mentioned before. You'll have to experiment a lot and my suggestion would be to keep a record of some type that shows the metal gauge your using, weather temp and humidity, and the settings that work best. Also, make notes as to speed, wire gauge and other things to watch out for, etc. It helps if you have your our reference material tailored to your style and machine. Saves time down the road too. One thing I learned last week was to use a strip of copper behind your butt, gives you something to attach to. Like momma used to say "practice makes perfect". Now, go wear that sucker out!
A couple more bits.... As stated above clean metal is imperative,BUT remember if only clean on the outside,you wil get contamination of your shielding gas from the inside of panels being painted or undercaoted.... This smoke pretty well dimishes the shieldiing gas's effectiveness. Remember-the gas's purpose is to evacuate the oxygen or other contaminants from the weld arc....... On another subject- Brazing is a strong method of joining steel just never do it on a car body which filler is intended to be applied over the brass. The body filler will release its grip [and fall off] after the brass oxidizes under it.......
I'm in agreement on hammering Mig Welds-I do it, after all, it's the same rod as Tig (ER70S-2 or 6)-the problem is the thickness of the Weld, so you have to grind it down first (front and back). As for gettiing the Welds ground, I use a lot of different stuff-I use 3" Roloc's a lot (36 Grit, then 50, Surface Prep), but for the first go around I really like using a 5" 36 Grit Disc on an air powered Grinder-takes it down fast (I sometimes use a Flap Disc on my 4 1/2" Milwaukee), then I graduate to the Rolocs-that works the fastest for me, and it keeps the Metal relatively cool.
Well, a tip I haven't seen for blowouts on thin metal is to take a piece of copper pipe and hammer it flat, or to the shape of the piece you're backing up. The weld won't stick to the copper. If you have a long, flat seam, you could hold a piece of flattened copper to the bottom of the floor panel with a couple magnets. A warning though, those welding magnets kinda suck for any sort of arc welding, the magnet draws the arc towards it.
It has been recommendeed to me to try the "Easy Grind" mig wire. Anyone tried hammer welding sheet metal with it? Thanx Powerband
Well guys I have tried a few of the suggestions, excpet for the gas welding. I turned up the heat, and speed, and damn that worked like a freakinc charm. I was in heaven. I had several cracks finished up in a very short time and the metal was very cool and no warping at all. I am still workin on the grinding parts thought, I bought some new wheels from a friend of mine, but will behittingup welding house later this week. I need some more mig gas as well. I ran out oops. If anyone else has some suggestions please feel free to put them down. I am going to look for some of that harris wire as well this week. I need some suggestions on sheet metal, as I have a few patch panels I need to make too. Is there a particular type of metal? cold rolled, hot rolled? galvanized etc. I heard cold rolled was what to use. but not really sure of that source. Will
Cold rolled steel is the metal of choice, but I know some guys that swear by hot-rolled, pickled and oiled. The hot rolled steel is a bit softer and easier to shape, and the pickled and oiled surface is pretty clean too. Oh, and the hot rolled is a bit cheaper. Tim D.
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