Crash course on welding(MIG): Penetration?

[Yota Up]

First of all, I know nothing.  Just got a welder and about to learn by simply throwing metal onto everything around me.

To save me some time in trying to figure out the right combo, I'd like to ask for your input on getting deeper penetration.

Welder is a 120V, 90amp Century MIG.  Using .8mm wire.  Cutting the bed and bobbin it, and cutting doors and welding in the top plates are the projects here.

I need to know what wire speed to use, in combo with the heat, and the gas.  It's C-25 gas(75 A).

Here's what I'm doing now:  Gas is at 10 CFH, heat is at 7(out of 9).  Wire speed is at 3(out of 9).

Seems like I light it up, and just lay a bunch of wire on it.  Doesn't seem like it's actually joining the metal, more like it's just slapping more and more wire on it.

All I need is a push in the right direction.  Any principles or train of thought on this I can apply?

Thanks guys, I'm asking you because I value your opinions the most.

[Gittinit]

mabye slow the wire speed down some and move really slow? with sheet metal small hot tac welds are your friend.

[DTB]

yep slow the wire speed and maybe crank the voltage...just play with it until u find what works...there are some good sites for metal fabrication/ welding info..theres some stuff on the miller site...u can also analyze your welds from info found online...just make sure u know what u are doing if u are making critical welds.



what thickness metal u welding with taht setting?

[mickeyfinn]

you may get a few tips here. practice practice.    http://www.millerwelds.com/education/library.html

[*** YELLER ***]

Slow your wire speed down, make sure your material is clean and weld away, you should do some pratice on some scrap before you go at it on your rig, if your gonna' do it anyway, stich weld the body, make a tack go about 4 inches or so away from that spot and tack again as to not heat and warp the metal and keep goin' when you have reached the end start over and soon you  will be done remember to be patient dont rush it or the truck will look like  patience is a virtue these are not critical spots to weld but you  should pratice first, most anyone can do it it just takes time and pratice.

GOOD LUCK

[CTENG in KS]

Ouch...starting on sheetmetal may not be your easiest bet.  I'd find something a bit thicker, some scrap and crank the welder to max.  Get used to laying a bead on the thicker material, then turn the heat down or slow the wire speed a bit and try the sheet metal.

[Yota Up]

"what thickness metal u welding with taht setting?"

It's the metal scraps from the bed and doors of the Toyota.  (don't have any thick stuff to play with yet)
I'll check out those sites, and slow down the wire.  I'll keep the heat up and spot hit it.

Is my gas ok at 10CFH or should it be at 15 or 20?
Last question - should I be touching the metal I'm welding with the copper gas shield cover at the tip of the gun, or should it be an inch or so away from the action?

Thanks, guys.  You rock.

[DTB]

"what thickness metal u welding with taht setting?"

It's the metal scraps from the bed and doors of the Toyota.  (don't have any thick stuff to play with yet)
I'll check out those sites, and slow down the wire.  I'll keep the heat up and spot hit it.

Is my gas ok at 10CFH or should it be at 15 or 20?
Last question - should I be touching the metal I'm welding with the copper gas shield cover at the tip of the gun, or should it be an inch or so away from the action?

Thanks, guys.  You rock.

OH! didnt know u was welding sheet metal! just spot welds......alternating areas to prevent warping..NO, do not touch the tip to the surface......the gas on our miller is set at 15 but u should follow manufacturers recommendations for gas setting

[locktup]

Some welders have a chart on the inside of the door where the wire spool is. 120/110 volt welds can give you a hard time until you have it figured out. Best bet would be like others have said already get some scraps of what you are welding on and play with the different settings  .

Jason

[Duffil]

another thing, if this unit also welds with flux core, make sure the polarity is set for gas, inside the welder.  Flux core is opposite polarity from solid wire/gas.  If it's set wrong, the weld will just lay out on top of the metal(no penetration).

[Willy Mammoth]

another thing, if this unit also welds with flux core, make sure the polarity is set for gas, inside the welder.  Flux core is opposite polarity from solid wire/gas.  If it's set wrong, the weld will just lay out on top of the metal(no penetration).

Negative gun with gas will give the maximum penetration.

I run 20 psi on the argon/Co2. If you can get by with less and not get porosity (pinholes) it may save you some gas.