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Samckitt
03-12-2007, 02:28 PM
I just can't seem to get a good looking weld from my Lincoln powermig 220 & was wanting to know if some of the experts would show what a good weld looks like welding 2 pieces at 90* & just laying a bead on a flat surface. Maybe I just can't get what I think is possible.

Thanks

protour_chevelle
03-12-2007, 02:36 PM
First off, are you left handed or right handed? If so what way are you starting from(left to right, vise versa). You gun tip should be 45degrees of the 90 in your angle with roughly 15 degrees inclination(towards the opposite way you are going).

If you are right handed some guys go right to left with the ass end being dropped down for the 15 degrees. Some start at the left and go right with the same idea for the 15 degrees. You will get more penetration(well easier to get penetration) going right to left.

You can now use a slight step or weave motion. Pull trigger, get arc going, move forward a bit and come back into about half to a 1/4 of your previous weld, and repeat.

Hopefully that makes sense. If not let me know and I'll try to clarify more.

https://static1.pt-content.com/images/noimg.gif

is what your going for/\/\/\/\

Samckitt
03-12-2007, 02:45 PM
Yeah that is what I want. I am right handed, doing pretty much what you described. Except I didn't do the "2 steps forward 1 step back" routine. Still I get it to pile up too much, If I turn the heat up then it spit & sputters like not enough wire is coming out, if I turn the wire speed down I get the same. I'll go try the "2 forward 1 back" with & see what happens. Thanks Matt.

Samckitt
03-12-2007, 03:05 PM
OK here are 2 tries. With some practice would be better.

Samckitt
03-12-2007, 03:09 PM
Here is the second one, closer & cropped. Lots of splatter...?

Goatman
03-12-2007, 03:31 PM
Dirty metal.......

kamaroman68
03-13-2007, 05:21 AM
looks like dirty metal and maybe an incorrect gas setting. my welds look like that also and i am taking a welding class. i think consistency is also a major part in welding. my beads are never the same size. to me it looks decent. chris

Samckitt
03-13-2007, 07:54 AM
Not enough gas flow maybe? It was outside, maybe a little too windy.

Goatman
03-13-2007, 01:31 PM
Poor gas flow would leave pits in the weld itself. Just like welding with the gas still shutoff...

protour_chevelle
03-13-2007, 06:48 PM
Poor gas flow will cause porosity. Too much gas flow will cause porosity.

What gas are you running? With Carbon Dioxide gas you should be around 20 CFH

JMarsa
03-14-2007, 12:44 PM
As a novice in a class also, most of my splatter is cause by improper angle and/or proximity to the work piece.

--JMarsa

Goatman
03-15-2007, 04:08 AM
I would say he's probably just going to fast/has his wire feed up too high and he needs to clean the metal better. Perhaps being too far away would cause splatter like that...

Samckitt
03-15-2007, 12:16 PM
Chris (Goatman),
Of the things you mentioned, it could be wire feed or need to clean the metal better. Gun was very close to the weld & I was going very slow. Gas flow was on around 30, I sanded rust off both pieces of metal. I'll try again when I get a chance & mess with wire speed.
Thanks,

protour_chevelle
03-15-2007, 08:06 PM
From your contact tip to end of your wire... You should be 3/8".

Samckitt
03-16-2007, 02:22 AM
I might have been a little closer than that.

z28orshoot
03-16-2007, 03:13 AM
here is a couple of things to check.

make sure you have solid wire not flux core.

make the polarity eletrode positive meaning the wire is the (+) pole and the ground is in the (-) pole of the welder.

have both pieces of metal clean NO RUST

you might try a 75%Ar 25%CO2 mix ...this reduces splatter and has better overall apperance

the splatter could be caused by several things like wire speed too high, voltage too high, electrode to long, dirty work piece, insuffecent gas flow, and dirty wire.



hope this helps

Samckitt
03-16-2007, 09:34 AM
I have solid wire.

Almost 100% positive polarity is correct.

I used an angle grinder to get rid of rust, maybe not good enough.

Am using a mix on the gas, I assume it is 25/75.

I'll double check.

Thanks,
Scot

Gordz32
03-16-2007, 04:39 PM
Heres a helpful hint, Set ur gas to the desired level ( useually anywhere from 12-20CFH), Get a scrap piece of steel, clean it, and fire away, hold the trigger down and adjust ur setting so that its a nice bacon sizzleing sound. When thats done your ready to go. Don't skip on cleaning the metal. Get some tip dip, and make sure there is no wind in the area. Do that all that and you should get some nice welds. Maybe its me, but I don't worry to much about position of the nozzle in relation to the material, practice makes perfect. Goodluck

Steve68
04-09-2007, 05:12 AM
Gas flow is too high, I was getting bad porosity this weekend, but I was also welding aluminized exhaust pipe that was old and used, I checked the reg when I got home and my gas flow was too low, less than 8, turned it up and it worked like a dream!!

Hobart 140 solid wire, mix gas

Samckitt
04-09-2007, 12:38 PM
Gordz32 - Adjust what while holding down the trigger? Gas or wire speed?

Tom Vogel
05-06-2007, 08:41 PM
Those are not really bad GMAW welds. A certain amount of spatter is a given, make sure your nozle is clean andyou could also use a stopoff (an anti spatter spray), on the adjacent areas that you want to get the spatter off. Or you could learn tig... thatll give you a clean weld. By the way, the stop start stuff is not done on mig, if anything, just an imperceptible side to side to make sure of bead wet in. (really... just imperceptible)
Someone is going to disagree with me on this... check the welding forums (Millerwelds or Hobart message board). Its funny how many guys see a nice tig weld and go about trying to make a simple mig weld look like a tig bead, even if it does nothing to add integrity to the weld. Kind of like the big chrome exhaust cans on the back of Honda Civics.

parsonsj
05-07-2007, 03:51 AM
Its funny how many guys see a nice tig weld and go about trying to make a simple mig weld look like a tig bead, even if it does nothing to add integrity to the weld. Kind of like the big chrome exhaust cans on the back of Honda Civics.I'm sure we all have our little quirks, but trying to make a MIG weld look like TIG welding isn't why I stitch sheet metal. Stitch-welding sheet metal lets me get full penetration, and to lay the bead low to minimize cleanup grinding without blowing holes in it.

jp

Tom Vogel
05-07-2007, 06:47 AM
I'm sure we all have our little quirks, but trying to make a MIG weld look like TIG welding isn't why I stitch sheet metal. Stitch-welding sheet metal lets me get full penetration, and to lay the bead low to minimize cleanup grinding without blowing holes in it.

jp
Sure, I wasnt talking bodywork...thats fine to control heat. His welds were on structural metal.:)

parsonsj
05-07-2007, 07:00 AM
:twothumbs Agreed. Stitch welding should not be be used for structural welding.

Cool.

jp

MonzaRacer
05-31-2007, 08:30 PM
One trick while your practicing crank the heat all the way up and practice on heavy stuff then play with your wire speed to getthe "bacon sizzle" then back off on heat till it starts balling up or not penetrating goo then go back up.
also having a variable speed unit it works better I have one with 4 steps on 2 switches.
It still works and all.
Also I love antispatter gell, weld few seconds, gettip hot and push tip into it and get her coated good.
Then get started welding and practice.
As you get good penetration and sweet welds then you can start playing with lighter stuff.
Also use 75 co 25 argon,keep the flow high in windy areas. Also you can buy weld wire thats for "dirty metal" but it does make some extra spatter some, its not flux core it got a coating on it.
We use it in the shop I work in.
Also if its a 110 welder make sure you have heavy wire to plug(like 10/3) and a good solid 30 or 40 amp breaker, a weak breaker will not always trip it will try but then it wont. Hadthis at my dads and spent cash on a double duty 30 amp breaker and it welded much better. Standar 30 would try to trip but not completely trip. I think they were just cheap.
also buy a auto shade helmet best cash spent and get lots of vicegrips and cheap clamps (if you can get them with brass screws slag wont stick.
Good Luck

pav8427
06-02-2007, 04:23 AM
Our Power migs at the shop are touchy when it comes to grounding and rust/dirt. Make sure you don't run a plasma cutter while the welder ground is hooked to your table or part. It can back feed and fry some of the stuff in the welder.

Doug