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View Full Version : learning to MIG weld....


AJ_Fritz
09-24-2008, 05:06 PM
just some tips and trick for the novice.

some simple rules:

use the right gas for the right material.

welding aluminum with a spoolgun your going to need 100% argon.

welding carbon steel your going to need either 100% CO2 or a bimix of 75/25% Argon/CO2.

welding Stainless Steel your going to need a trimix gas of 90/7/3% heluim/argon/CO2 you can weld with carbon gas but the weld will be very hot and turn black. helium cools the weld.

now a little discussion on actually welding.

its hard when your a beginner to wrap your head around what does what when adjusting the voltages and wire speeds. always remember that the wire carries the amperage and that equates to heat and penitration. this is very importent to remember. i know 20 year veterains that still think it only takes voltage to get a hotter weld. voltage and wire speed is a marrage if you increase one the other needs increased. if you increase the wire size you wont need as much speed.

if you change materials say from carbon to stainless and everything is the same your going to have to increase the wire speed. it has to do with resistance. stainless has a lower electrical resistance then carbon and has a slower heat transfer rate from the weld joint.

think you got it set up pretty close. does it sound like frying eggs? then its cooking just right. i can set up a welder pretty much all by ear. spitting and sputtering? that would either be a globular weld or a little more wire speed.

weld looks like yarn then turn down the wire speed if it's a thin material,or up the voltage if its thick.

tick tick ticking at the start of every weld. feed problem or voltage problem. if the liner is good and the right size for the wire then turn the voltage up a little. or if it welds fine afer a quick stop and start nip the bud off the wire before starting the first time. stainless will do this alot. it oxidizes and doesnt like to ground out to start the arc. will bend over until virgin material is touched and start the arc there. so nip the bud or have a starter pad close you can clear its throut with.

i know guys at work that hate stainless. alot to do with it sticking in the tip. tip sticks are a feed problem. if the feed rate is not constaint and consistent then your going to have problem. if at any time the arc changes during a weld and your rate of travel doesnt start looking for a rate of feed problem. the easiest way to find this is work from one end of feeder to the other. pull the tip off, disconect the drive rolls and put a little slack on the spool and pull on the wire. it should slide through the whip like butter. if it doesnt look for a kink in the cable liner. no kinks. then its in the drive rolls and wire holders. look for something rubbing or misdirecting. whatever it is fix it. nothing messes up a good weld like a feeder problem.

sometimes someone will try to run a .030 wire in a .045 liner. you can ussually get away with this if running carbon but stainless hates it. every other weld will start with a tick and every 10th start will be a stuck tip. depending on how well your feeder works a tip stick ussually results in a birds nest or a unclearable tip.

AJ_Fritz
09-29-2008, 05:21 PM
some more useful crap... lol

i constantly see people jamming up the nozzle with spatter. now some spatter is normal but when you cant go more then 5 inches without cleaning it out something is wrong. when your welding right the wire should be about a 3/8-1/2 inch sticking out of the tip before the arc is visible. if youve got the nozzle jammed up into the weld then its to friggen close lol. if you cant get that far away then turn the wire speed up. now the closer the nozzle gets the hotter the arc will be. the farther away the cooler the weld will be and it will begin to pile on you. this is your fine tune for final heat settings.

if your burning though in a continous weld dont be afraid to stop and start. dont wait to long before you restart. right after it stops glowing bright hit it again. a mig weld when started for the first time will always be cold. start the puddle then move. linger a little then move again along the joint.

alway find a peice of scrap to play with the same gauge as what you will be welding. run a bead. look at the bead. look at the backside. if the bead looks like goose sh!t. turn the heat the volts up, or the wire down. if the weld is pushing though to the backside but the weld looks great. turn the wire and volts down a little.

verticals are nice if the gauge is thin and you cant put alot of heat in the base metal with out burning through. heavy gauges and plate should be welded horizantal to get good penitration. if you cant weld them horizontal then put a 2nd pass over the first vertical. heavier gauges need heavier wire.

D94R
09-29-2008, 11:39 PM
Good info.


But, what about welding different gauge material? I understand to concentrate the heat to the thicker material, but what are some other tricks?

The frame stiffeners for the Jeep are 10gauge, whereas the unibody is 16gauge.

AJ_Fritz
10-30-2008, 04:49 PM
welding stainless steel:

instead of getting a tri-mix gas you can buy a little extra equiptment and save yourself some headaches.

your going to need:

a mixer valve. (its basically 2 check valves)
another flow regulator.
a bottle of heluim.

so now you will have 2 bottles hooked up to your mig welder. one bottle will be 75% argon/25% carbon dioxide. the other will be staight heluim.

set the argon/cO2 flow regulater to 5-10 cfm and set the heluim regulator to 40 cfm. make sure you have a helium flow regulator or it will be set to high. if using an argon regulator for the helium set it to 15 cfm argon. your ready to weld.

Oldmandan
05-31-2009, 01:18 PM
Aj,
Ever tried to tack 304SS with a mig, setup with 100% CO2? I'd have a buddy final weld it with a TIG. But he's a busy guy, so I'd like to do all the fitting at home. Or it'll probably take me a year to it get back from him, by the time he gets to it.

Anyway, I did one time build grills for my wifes Scion with a steel perimeter and SS mesh, but I had to weld on the steel and "push" the weld into the SS for it to work. Although it wasn't ideal it worked? 304SS to 304SS is a different story though. I probably will have to get a piece of scrap tube and try it, but I thought I'd ask you first in case you've tried it already?

AJ_Fritz
05-31-2009, 01:48 PM
OMD it will spatter like no other with co2. if your just tacking up it should be alright but i would prefer to tack it up with 75/25 argon/co2. tacking isn't all that bad. it's when you try to run a bead that both co2 and 75/25 get crappy. the weld will get black as a well diggers ass and brittle. not to mention you will be spitting bb's all over the place. use a good splatter-proof!

Matt drill holes in the 10 gauge and use a plug weld to join it to the unibody. don't run a continuous bead around the perimeter. use a 1/2" stitch weld ever inch and then come back and fill the gaps after a short cool down if you want it to be water tight.

Oldmandan
05-31-2009, 02:00 PM
OMD it will spatter like no other with co2.

Yes, you're right it does.

Thanks for the info., I was holding off because I thought it would be a waste of on afternoon. Now I think I'm going to give it a shot

D94R
05-31-2009, 09:21 PM
Matt drill holes in the 10 gauge and use a plug weld to join it to the unibody. don't run a continuous bead around the perimeter. use a 1/2" stitch weld ever inch and then come back and fill the gaps after a short cool down if you want it to be water tight.

LOL, done months ago :moon: The stiffners were already plug drilled. I just performed what I already knew. Worked out well. I didn't make it water tight as there would be no way to let the unibody rail drain then.

Riddle_Rob
06-01-2009, 10:14 PM
What about a Flux Core MIG? I just bought one. I just want to do very very basic welding without gas. So I bought the gasless wire (flux). What's it good to use on? My hopes.... sheet metal and the like.

Oldmandan
06-01-2009, 10:32 PM
You should be able to buy a kit to convert it to gas. You don't want to weld sheetmetal with it. Really messy welds, and it'll probably warp the crap out of it.

Take AJ's advice on how to set up the bottles.

rangergt
06-02-2009, 09:38 PM
What about a Flux Core MIG? I just bought one. I just want to do very very basic welding without gas. So I bought the gasless wire (flux). What's it good to use on? My hopes.... sheet metal and the like.

You can use it on pritty much any thing but it is a lot messier, lots of splatter and slag. I've used my mig with flux core wire for years and I had mine set up with gas for when I really needed it. It'll weld right thru paint, oil, rust, just about anything and leave a half decent bead, not that I recommend doing that. It's just not as fussy about being clean like when using gas. Good for welding outside as well, no gas to blow away. Using gas has it's advantges but if it's what you have use it. Just be prepared to do a little extra clean up when your done. And gas is better for sheet metal.

TURBO Ranger
11-03-2009, 11:00 PM
True, flux doesnt do to well on sheet, but if you have a small 110 one, they can be real handy. the nice thing is not having to get a bottle, but like Rangergt said, its nice to have so you can do stuff nice if need be

phoenixfriend84
07-06-2010, 06:59 PM
Well because of my interest and passion for cars and am getting ready to go to school for welding. Then ill see about finding a way to learn some fabricating and machining and engineering. I want to contribute to the aftermarket. I don't know why but these great little trucks have so little aftermarket. Its a shame. Look forward to the future and what it holds.

jfive
07-06-2010, 08:01 PM
Good deal. I am hopefully gonna go to school to futher my knowlage of welding, since I really want to learn tig welding. I recently purchased a flux core harbor frieght, and it has been handy for welding stuff back to gether. The wire is exspensive, but I can weld in the wind, on rusty painted metal, so its worth the extra cash. I don't weld to thick of stuff though, cause it just doesn't like it much. I think if you preheat the metal with a pencil torch it helps it from splatering too much in the beginning.

jfive
01-17-2011, 10:29 PM
Just some arc/stick rod for stainless steel. Got 3/32 and gonna buy a few pieces of 304 stainless pipe for practice. I think that fact that it only needs 50 to 90 amps might make burning thru a bit less likely. Gonna hold off on buying any more welding equipment, until I can afford a multi arc,tig,plasma. I dought anyone has used stainless rod, but maybe aj, but if you have how easy is it compared to some 7018,6011,6013. Stuff I got is universal DC, or AC. Might have to buy a small DC arc welder if it doesn't like AC.

AJ_Fritz
01-18-2011, 11:45 AM
you'll like stainless rod.... so much so you wont want to use anything else lol.

Riddle_Rob
01-18-2011, 06:43 PM
I'm going to reattempt to get into welding again right shortly.

A friend and I are splitting on a welder so as we can buy something better then a Canadian Tire pos.

We're wanting to weld anything from body panels to rad supports to frame/suspension.

We both like the idea of a MIG/Flux as we both have experience with a spool gun but, what do you guys suggest?

jfive
01-18-2011, 06:57 PM
Well I just signed up for college to get my welding and fabrication certifacate. 1st semister with books and lab fees 8 credits 1250.00. Ouch. Hopefully I will get some sort of grant money or unemployement finacial aid. I like the idea of having a 110 mig welder. You can do alot with one. Also for a roll cage it can only be done with mig or tig so thats a good reason to get one. I am holding out for a Tig/Arc/Plasma. The one I want runs about 1699.00 but does everything and has watercooled torch. Will cut 7/8" metal and welds 1/2 steel or 7/16 aluminum. You can pickup a stick wedler for 100.00 though and do alot of stuff.

fordnut71
01-18-2011, 07:16 PM
good luck jfive on the new venture.
i did my schooling for it back in the mid 90s.

AJ_Fritz
01-19-2011, 11:48 AM
I'm going to reattempt to get into welding again right shortly.

A friend and I are splitting on a welder so as we can buy something better then a Canadian Tire pos.

We're wanting to weld anything from body panels to rad supports to frame/suspension.

We both like the idea of a MIG/Flux as we both have experience with a spool gun but, what do you guys suggest?

anything with sheilding gas.