Welding penetration tips...

[howiess2000]

I have a Lincoln 140 115v MIG, I'm using .25 wire CO2/Argon mix. This thing is rated to weld 1/4 inch, but I'm not able to fully penetrate 1/8" I saw in a previous post that a good ground and clean metal is essential, and I will make sure I have that, but do you have any other tips?

Thicker wire?
Slower or faster wire speed?
Flux core vs. solid wire and gas?

I saw some people post that a 115v should do the trick, so I'd like to see if I can use this welder to do my heavier welding, but if I have to go get a used 230v welder, then thats what I have to do.

BTW, I practiced with the fluxcore that came with the welder and I just got a tank of gas....what a difference!!
Thanx in advance.

 

[deerchooper]

i like solid wire better, dont have to chip after your done. welding with a smaller mig, trying to get 1/4" deap. i would grind both sides on a angle, like a V when put together. also leave a little gap 1/16" or so. then you got your full 100% 1/4" weld. each machine is a little different, hell mine changes from time to time. but for anyone to tell you put your welder here and there, will only get you close.

also new metal. it looks so clean but its not. theres mill slag on it from it getting formed during the heating process. if you were to take a flapper wheel for a grinder and hit the top. you will see what im saying. you have about a .020" coating of this slag. so grind it all around before you weld. some will say, well thats nothing, but it does make a differance and keeps your welds clean. not abunch of stuff in the core of your welds.

a little trick, stuff i learned over the years for welding thick stuff. you dont have to fill in one pass. most 110v welder will do 1/4" but you could also do 1" of you had to with the same welder. how you ask, well you have to make mulitable passes. V it out. lay down your root pass, clean, weld to 1 side of the V, clean, do the other side of the V, clean. so in reallity your stacking welds, like a stair case over and over till you fill it evenly all the way out. we do it at work all the time with 480v stick welders, we even use 7018 5/32 or 7024 1/4 (only if its flat the 7024) welding rod.

go look at some large industrial stuff. look at the welds, most of them are little beads of little welds.

 

[RPM]

Deerchopper pretty well covered it. Also as you stated be sure to clean everything. Tack everything real good first and don't be afraid of multiple passes.

 

[howiess2000]

Hey guys...
I just wanted to say thanks. I got a chance to try the welding techinques that you suggested. The welds penetrated for the most part, but it was pushing my little welder to the limit. I'm going to invest in a 230w machine and not worry about power anymore.....anyone need a Lincoln 140HD???
Thanks again

 

[ohio_rat]

you should be using at least .30 dia wire for that, .25 is more for sheet metal work

 

[anvil]

keep that welder for doing body work

 

[deerchooper]

i had to buy a spool of wire the other day, im running .035 wire.

 

[ANNAMEL]

I weld for a living and if your life depends on it i would use 035-220v. Better safe than sorry.

 

[Kustom Mayhem]

Keep the 110 mig for the light stuff. I stick most of the thick stuff and torch just about everything else but 110 migs are nice for the small jobs

 

[donsrods]

I'm really glad you posted this as it points out something we see so often. Guys are trying to weld frames and critical suspension pieces with 120 volt welders and they simply aren't up to that task. I know someone will post that they have done this for years, but I sure wouldn't risk my life on doing it.

We all have budgets and sometimes we would love to have a 220 volt mig, but it just is not in reach for us right now financially. Been there, done that. So what I suggest is that you use your 120 volter to tack weld stuff then take it to a pro welder or a buddy with a 220 volt unit and have it finish welded. No shame in doing that, and that is what I did for years because I didn't trust my own welding on really critical stuff.

We have to remember that we are building a car that we want to safely drive our families around in and can't risk anything ever going wrong.


Don

 

[93blazer4dr]

I'm really glad you posted this as it points out something we see so often. Guys are trying to weld frames and critical suspension pieces with 120 volt welders and they simply aren't up to that task. I know someone will post that they have done this for years, but I sure wouldn't risk my life on doing it.

We all have budgets and sometimes we would love to have a 220 volt mig, but it just is not in reach for us right now financially. Been there, done that. So what I suggest is that you use your 120 volter to tack weld stuff then take it to a pro welder or a buddy with a 220 volt unit and have it finish welded. No shame in doing that, and that is what I did for years because I didn't trust my own welding on really critical stuff.

We have to remember that we are building a car that we want to safely drive our families around in and can't risk anything ever going wrong.


Don

you hit it on the head with that. i have seen alot of people trying to do the job with a small welder that cant do the job. its very unsafe and just stupid.
im liking this site more and more the people on here are real honest.

like others said get a 220v welder and run 035 wire and you will be just fine.
i have a miller 252 mig welder and its awesome it can do any job i need and i also got a tig/stick welder

 

[Screamin' Metal]

I'm really glad you posted this as it points out something we see so often. Guys are trying to weld frames and critical suspension pieces with 120 volt welders and they simply aren't up to that task. I know someone will post that they have done this for years, but I sure wouldn't risk my life on doing it.

We all have budgets and sometimes we would love to have a 220 volt mig, but it just is not in reach for us right now financially. Been there, done that. So what I suggest is that you use your 120 volter to tack weld stuff then take it to a pro welder or a buddy with a 220 volt unit and have it finish welded. No shame in doing that, and that is what I did for years because I didn't trust my own welding on really critical stuff.

We have to remember that we are building a car that we want to safely drive our families around in and can't risk anything ever going wrong.


Don

He's right! Now, on sheetmetal, that 140 or 120 with .024 wire will let you chop tops. I use my 220v. Lincoln 350 for the frames and such.

argon/co2 75/25 is good for moderate to thin stuff, To really burn in, on heavier stuff...run .035. Doesn't hurt to have a bottle of CO2. I usually tack weld with my 175 pro with .024 w 75/25, then I burn it in with my 350.
On bigger-thicker stuff, .045 innershield works great.

Welding is a art. You just don't 'do-it'! Make sure everything is clean, have a small gap/ bevel, if it applies. A gap will allow you to burn in. Butted up pieces will allow you to weld thinner stuff without burn-thru quite as much. Go for as much penetration as you can get, without undercutting on the sides...(wagontracks)....

If you have a big weld....on a 1/4 in section that butts to the side of a frame rail, you want penetration....you don't want it laying on top, slow down your speed some, correct technique is paramount! Use 2 or 3 smaller beads if you got to, but get good penetration!

Frame stuff should be done on a 220 machine. Always bevel, clean and have at most a 1/16 gap on the smaller maches. The bigger machines have enough umph to sink the welds in without bevels. Tack weld first, clean, then check for alignment. Then, you can go for the gusto!

 

[Bowtiestang]

I use my Miller (110v) with c-25 and .30 wire on 1/8 and 3/16 and on my race car roll cages with no issues. BUT it cant do 1/4 for $%it. I have it maxed out on 3/16

 

[moparcowboy]

you should be using at least .30 dia wire for that, .25 is more for sheet metal work

I agree with Ohio Rat 25 to small

 

[cantwell.colton]

i hate beveling with a passion lol -- but it works... but a 110 should be able to weld 1/4 in. fine - like said - dont use it for a frame or anything like that - but say a BBQ pit or bumper - as long as you bevel and make a few good clean passes -- remember to clean the weld as good as you can and let it cool before making another pass but youll burn through some wire thats for sure... sometimes stick welding just makes more sense..

 

[Rat'l Trap]

-- remember to clean the weld as good as you can and let it cool before making another pass but youll burn through some wire thats for sure...

what do you clean a weld with, or how is it done, and why? Does the welding process produce a surface that future welds wont stick to? Also (pardon the rookie questions) why let it cool? Isnt the idea to heat the metal to the melting point to make it "one piece"?
Thanks in advance.

 

[Screamin' Metal]

well....what I do is use my 'jitterbug'....air descaler...or a air hammer. Then wire brush it, with with a hand wire brush or a brush on a grinder...

You want your weld clean, as in all the scale or flux off it, if not you can have scale inclusion....big time nono...

If its thin stuff....you might want to let it cool...also if your using a small 120v. welder or something like a 120 or 140 mig.

You want a slow steady movement across the piece to be welded, and it should look uniform and fairly smooth. If the steel isn't thin and your using .035 wire, turn your heat to the next to the last notch on your voltage tap and run about 75% on your wire speed. The thinner the steel the faster you have to go. If your getting good penetration, you should flip the piece over or look at it from the rear. You should see a weld on the reverse side of where you were welding. If you see a gap in the 2 pieces of metal with almost all of the crack filled.....your at about 90% pentration. Slowing down slightly will fill that in.

The thinner the wire, the thinner the steel. Thicker the wire , thicker the steel. .024 is good for sheetmetal. .030 is good for thicker sheetmetal on up to about 3/16. .035 is go up to about 1/4 to 5/16.....depending on the welder. The thicker the material, the bigger the wire size, the more heat it needs to melt the steel....

On sheetmetal....you want to keep it as cool as possible, to keep the warpage to a minimum, especially if your chopping a top or doing body panels. If your new at this....you should watch someone do it the first few times before you try it yourself....especially if you want to use the item or ride in it or on it.

I've been throwing steel together and making sparks as a certified welder since the early 1970's.... its a art to it. Not everyone can do it. The more rods or wire you burn, the better you get at it. I'm closing in on 40 years of it now....and like I tell the guys that ask me if it'll hold...."I don't do this for my health, and I don't need any pratice. And if it breaks , I should happen about 300 MPH....", then they usually shut up.

Happy welding!!!

 

[waldos_1]

Well on heavy stuff ,you can preheat the metal and this helps a lot,but you have to know what ya doing not to burn through,with the mig gun when all is right you will hear that little buzzzzzzzzzzz then ya have it about right

 

[cantwell.colton]

what do you clean a weld with, or how is it done, and why? Does the welding process produce a surface that future welds wont stick to? Also (pardon the rookie questions) why let it cool? Isnt the idea to heat the metal to the melting point to make it "one piece"?
Thanks in advance.

just like screamin metal said - you can just clean it off with a wire wheel on a grinder - even just a grinding disk if you want.. -- you can weld fine to welds - but if theres slag or rust - there will be areas that dont weld causing small cracks and/or pockets within the weld (thats why its a NONO)

and you arent INcorrect with your description of welding and cooling..
but also no entirely correct.... Screamin metal explained about burning through and warping so im not going to go into that - but heating any metal changes its make up -- it changes the porosity of the metal and can make it brittle etc... also, let the weld cool on its own -- rapid cooling can also cause weld defects - just like when you throw a hot pan or glass into cool or cold water and it bows or shatters.

also just a tip
if your questioning your welds, you can take a little bit of diesel and spray it on one side of the weld - and within a few minutes it will cause a wet looking spot on the other side if theres a crack all the way through... not really necessary for most applications but you never know when you might need that information

 

[cantwell.colton]

just a side not - if you already have a small mig and youre wanting something to handle the heavier stuff i strongly suggest finding someone with a stick welder that knows what theyre doing and have them help you out and give it a chance before buying anything..