I haven't gotten that figured out with wire feed myself. With stick I'd run less heat and whip the rod a bit.

 

I can't stress the eye protection hard enough. I've had metal removed from my eyes 6 seperate times. 3 of those times were from the same piece of metal. Took 3 seperate trips and 3 Dr's to dig it out. I was wearing safety glasses when it happened. Now I wear safety glasses anytime I'm in the shop(I'm a tractor mechanic) and I wear goggles anytime I'm grinding, sanding, using the chop saw or my die grinder.

I don't wear ear protection as often as I should, but I do wear earplugs everytime I ride.

 

SO TRUE
glasses are not enough when grinding
i use goggle and face shield on top.


i was wearing glasses when i got a tiny sliver in my eye.
i noticed it, but it wasnt that bad. but 3 days later i went in
and the dr dug it out, he told me my cornea had almost grown over it completely. and it was totally rusted from the moisture in my eye.

and a friend of mine had safety glasses on and had a large sliver slip past his glasses and lodge itself in his eye..
it was visible in his eye from 5 ft away.. ****ed up his eyelid and had some serious vision issues for awhile..

 

By "upside down" welding, I suppose you are talking about overhead welding. I haven't done a lot of overhead MIG, because in my experience MIG was mainly for rapid fabrication, and that was usually welded flat wih the welder standing up. Most of the overhead welding I've done was stick welding, either E6010 or E7018.

The main thing about welding vertical or overhead with MIG is to make sure your machine is adjusted correctly. MIG used DCRP (direct current reverse polarity) and constant voltage power supply. I imagine that modern wire-feed welders all use this design, but before you buy one, check to be sure. (I haven't bought a welder in about 25 years, so I'm not really up on the modern stuff.) A constant voltage MIG machine maintains the same voltage (potential) regardless of the amount of amperage drawn. This cuts way down on "sticking" the wire or burning back into your wire tip.

Make sure your wire stick-out isn't adjusted too short. The more stick-out, the more pre-heating of the wire when you pull the trigger (up to a point.) Make sure that your tip-to-work position is as consistent as you can manage to do it. If your welding distance increases it will cause an increase in voltage, and this will hav the effect of making the machine sem "hotter" resulting in more of a tendency to cause burn-throughs and drips. For thinner materials use a sort of "z"; or "lightning bolt" movement. V-grooving the two pieces to be welded will improve the strength and appearance of the weld. For a thinner bead, move faster. For a thicker bead, move slower.

But really, best of all is to tack it together on the vehicle, get good measurements, remove it and weld it in the flat position if possible. It is possible to weld vertical and overhead ith MIG, but I wouldn't choose MIG for that unless I absolutely had no choice. To weld overhead, like welding on my back in my driveway, I'd use a stick machine and run E6010 or 6011.

You also need to be sure you are using the correct diameter wire for the job. Vertical or overhead welding really requires a smaller diameter wire.
MIG wire used to come in a variety of diameters: 0.020, 0.030, 0.035, 0.045, 1/16 inch and 1/8 inch. I never used anything bigger than 0.045, and that was on a sub-arc welding machine that welded 1/4 inch plate butts. For overhead welding, I'd say run 0.020 wire and turn your WFS down to an appropriate speed. I seem to recall that I ran E-70S-3 wire a lot and 25-75 argon/CO2 gas. It's for mild steel.
If you are running flat and you've got the machne turned up too hot, you can (and a lot of people do) turn up your wire feed speed.

Back in the '80s I worked for about a year at a small woodstove manufacturer in Washington State. We used Miller wire-feed machines. The supervisor was about 20 years old (I was in my mid-30's) and some company big shot's brother-in-law. He knew zip about welding. Somehow he got the idea that if he turned up the wire feed speed that it would increase production. So I'd be welding away on a wood stove firebox and this jackass would walk down the assembly line and turn up the welders' WFS a little, which caused people's bead to be spoiled, then you'd have to grind out the screw-up, re-set the WFS and so on. I finally caught him doing it, and we told him to not touch the welding machines at all, period.

 

My advice... Buy a set of smaller regular cheap needle nose plies and keep them in the welder compartment... I weld with flux wire so my wire gets stuck pretty often and i find it easier to grab what little bit of wire is sticking out and push pull it to clean out the tip... The little tools for this aint worth a damn... Ive found the wire itself to work better... Lol... I also keep my box of spare tips in the welder incase it just gets to bad which of course does happen eventually...

 

Found this on pirate, i think actually testing your work is the best way to know how you are doing
"If you want to actually *know* how much penetration you're getting with *your welder's current parameters* on *your pipe* instead of just guessing and saying "Well I guess that looks OK" Nobody here can give you that answer just by looking at a picture. Anyone who claims they can tell exactly how strong a weld is by just looking at it is full of ****. If you want peace of mind - test your work. There's two simple ways I've tested welds myself in the past that I can tell you both will tell you a hell of a lot more than just looking at the surface of a finished bead. Neither way requires any specialized/calibrated/certified test equipment or expensive commercial testing labaratory fees. The whole point of testing is to learn from it and make yourself a better welder, not to just show off some certification card in your wallet.
Method 1 Cut and Etch
Take two small scraps of pipe from what you have and cope the joint and weld as you normally would. Next, take the completed weld and run it through the bandsaw making a cross-section of the sample joint you just welded. Polish out the cut with an 80 grit or finer flap wheel (the more highly polished, the easier your etched weld sample will be to see, 400 grit makes it very clear to see). Next, brush on some Ferric Chloride (It's an acid so be careful -you can buy it at any electronics supply as "PCB etchant") and brush it on the metal. Let that sit for a minute or two and rinse off with plain water. The etchant will allow you to see exactly how deep your weld is penetrating into the pipe - the weld will show up as darker than the base metal. If you see evidence of cold lap - Test is a fail. If you can't find any Ferric Chloride and still want to try this test, PM me and I'll give you a few alternate chemicals that will also work."

 

Can't believe I didn't see this thread before today...

I just bought a Lincoln 125pack Flux core welder, http://www.weldingmart.com/reconditi...k-pak-125.html and it hasn't even come in yet. I plan on using it for small jobs like replacing my floor pans and rear deck in my 95XJ.

Will this machjine do the job with the floor pans from Rock Auto? A friend said I only have to spot weld them and then seal them with silicon. I didn't want to try and just drill and pop rivet it.

 

I haven't checked this thread in quite a while, so I didn't see the question about the Lincoln 125. Sorry. But to answer the question, yes, a 125 amp Lincoln flux-core welder should be plenty powerful enough to handle nearly any routine welding job on a vehicle. I would be reluctant to weld up a crack in the frame with a wire feed welder, but floor pans? No problem.

But since you asked this question back in August, I'm sure you and your floor pans are all spiffy and new, LOL.

 

Sorry to go a bit , has anybody used Alumaloy, HTS2000, Wizardweld or any similar aluminium brazing products ? I need to do some minor repairs (and want to do some mods) to my aluminium boat. I cant afford a MIG welder that is capable of welding this material and I know my TIG skills blow. I see Alumaloy as a cheap way of doing these minor repairs (previous owner drilled about 8 x 1/8 holes through the hull).
just wondering if anyone has used this stuff to construct anything ?

 

My little welder even welds aluminum with aluminum flux wire... Just havent done it... Lol...

Use steel rivets and two part epoxy... You wont leak...

 

The boat is being stripped and prepped, I want to do the repairs pretty good as I'm about to spend several hundred on a good two pack paint job. No way am I using steel rivets on an ali boat ( dissimilar metals in salt water = bad ).
The boat is called "Butt Ugly" - currently an accurate name, I'm hoping that after the repairs, mods and paint it will be an ironic name

 

it would be fine on just a reg ole john boat which is what i figured you had... but not if you plan on sticking it in salt water... must be larger and nicer... i said steel cause aluminum rivets on a boat thats going to flex they wouldnt hold up... welding a aluminum boat i wouldnt go cheap on... aluminum car trailers dont hold up forever either... welds always end up cracking...

 

Been reading a lot of these posts and learning quite a bit. I'm one of the nuubs everyone is speaking about. I'm doing floor pans to the rockers and frame and ther existing pan pieces. I may be using one of the small MIG welders. It doesn't seem like the steering box that fell out for the one fella. I'm guessing the pans have some strength, but I don't think that I need the 1000.00 models for that, do I? This is all fairly thin metal. Thanks

 

i used my Hobart handler 140 for my floors... still on flux wire and itll burn through if you dont pay attention... gotta kinda start/stop it real quick so it doesnt have time to burn through... using a bottle makes it a lot easier to weld thin though...

 

Just get a bigger wire feed Mine will blow holes in truck frame.

On equipment repairs I burn 7018 sticks in the field and .045 solid wire in the shop. I only shy away from my mig on high-stress joints over 1/4" material.