Need some mig welding advice

Hi. with 0.23 solid wire what voltage setting and gas flow rate that you found successfully weld frame stiffeners to unibody without burn through ? Thanks

it all depends on the machine you are using, and where you are doing the welding. outside and a breeze will need more gas flow than inside a closed shop. that said, try between 10 to 15 on the gas flow. as for voltage/amps, you will need to experiment. make sure you have a very clean surface, no paint, primer, grease, or dirt. burn into the stiffeners first and flow it into the unibody. if your machine has a separate wire feed speed dial, keep it slow and speed up as needed. i normally turn the amps/voltage way up and a fast wire speed then just work faster. but if you are not used to working that way, keep it slow until you are comfortable speeding it up. if you are using a 240V machine, set it low at first. with a 120V machine turn it up. thats about all i can help you with if any. just experiment with your machine and it's capabilities. remember to burn the stiffeners into the unibody. you should be fine.

Depends on the condition of the welder, the cord/breaker you are using, etc. If your welder has a heat/speed chart, consult it and go from there.

On my 220v snap-on, i use 3/3.3, but that'll mean absolutely nothing to you. Learning to dial in a mig welder is a big chunk of being able to mig weld, be patient untill you get it 100% they way you want before you weld on anything you care about, and if you plan on going upside down, or switching to thicker material, adjust accordingly.

As far as 75/25% gas flow, IIRC, i use 18-22 cfm, depending on where i am welding, and how much wind that area has.

xcm.... which snap on welder are you using? i have the opportunity to get a snap on MM350XL for a decent price. my old miller 35 is still working great, but i am getting a lot of aluminum projects that are just too much for the TIG machine, and rigging the 35 to work with a spool gun is not easy. problem is the snap on spool gun is also extremely expensive and the machine does not come with one. just trying to weigh my options with either a new miller 212 with a spool gun, or the snap on. would have about the same amount of money invested.

dang, i should have used a PM. sorry for the highjacking ktfung.

Thank you for the inputs . I got a used 240v Millermatic 180 . I will be welding inside with the big garage door open . I was reading some welding book that mentioned you need to increase the gas flow rate when welding overhead especially vertical weld . I guess i was used to the higher voltage welding with the 3/16 plate while i was building a front bumper earlier . Now with the smaller wire and if i set the machine voltage low for 16 gauge welding that don't seem to have the power to melt the 3/16 frame stiffener . I did search on the post
someone said the trick is to spend most of the time on the thick metal first and once you get a good hot puddle then you move the hot puddle to the unibody side for a short period of time . But my problem is that i have the mig gun stick out so close to the weld probably 1/4 " or less that i can't even the puddle .

Any more suggestion or tips ? Thanks in advance

Don't worry about the gas flow. It's either "enough" or "not enough". More is a waste and less will leave porosity.

Practice on some of the junk metal you have removed from the truck or some scrap. When welding vertical you may need to change your voltage/feed settings but not the gas. If going up, run it a little colder and downhill, much hotter (down is much easier. If you feel the torch pushing back or bucking, turn the wire speed down. Get your setting and torch angle perfect for flat before going overhead.

Tip the gun the the side a little to see what is going on. Once you get good weld settings, make minor changes, not drastic ones. When the settings are correct, it should sound like bacon cooking and leave little rings of brown flux on the surface of the weld. Good Luck

ftwelder speaks the truth, id bet he does this for a living =)
I only ever adjust gas flow rate when dealing with heavy winds, or when your at the bottom of the bottle(of gas), and need to finish it off without compromising.

x2 about practice practice PRACTICE. Do not learn 'on the job'.

Keep in mind you are welding to galvanized steel so you will have toxic fumes to deal with and it will be harder to get a good weld.