Sorry guys but I have another welding question

[kamaroman68]

Sorry guys for all the welding questions but jopefully this will be the last one. I will be welding very soon 1/8 to 1/8 304 grade stainless steel together with my mig. Now I know normally you would use ER308 for this but the problem is that there will be a piece of mild steel approx .040 thick in between the two. Should I set the welder to the 1/8 inch setting for stainless steel using ER 308 and weld right through the mild steel piece? or should I be using ER 309 with a tri mix and weld right through the mild steel? Will this contaminate the weld? Thanks Chris

[kamaroman68]

So I am starting to wonder did I offend someone in these forums or something? Chris

[Travis B]

So I am starting to wonder did I offend someone in these forums or something? Chris

ya..... your normal guy can't answer this question.....be patient

[Matt@RFR]

Like a mild steel sandwhich with 304 bread? If so, what the hell are you building?? I've never come across a joint like that. How is it prepped? Will it get painted? Rossette welds? Spot welds? What?

Bottom line: If you have mild steel mixed with a 3xx series stainless, 309 is allways the filler of choice.

[kamaroman68]

Hey Matt thanks for the reply. This is going to be hard to explain. This may sound even worse but do you have a fax # that I could send you a hand drawn picture of what I am doing? Thanks Chris

[Matt@RFR]

530 877 1758

[Damn True]

Be patient. The two people most likely to answer your question (Matt or JP) have jobs that don't allow a great deal of computer time during the day.

[JoshStratton]

Hey guys.

I have been watching this thread and am interested in hearing the answer. You dont have to tell if it is top-secret, just wondering what you are making. You have some of us intrigued!

[kamaroman68]

Hey guys. I'm not making anything top secret just trying to figure out the best way to marry SS to much thinner mild steel. Basically took complete floor out of my 68 camaro for the art morrison max g chassis I bought. Instead of welding body directly to the frame as they suggest I am trying to make it an unboltable body. The SS comes into play because I live in NY home of the salt and snow all the good crap that eats away at metal. I intend to make the comple floor and firewall from SS. Matt and JP have been helping me all the way through so I like to chat with them specifically when it comes to welding and fabrication. I will post some pictures soon so everyone can see. Thanks Chris

[JoshStratton]

Awesome idea! I would be interested in hearing how that works out. Good thought!

[Matt@RFR]

Chris, is this right? If it is, then I'm gonna have to say to not worry about burning through the thin stuff, but do use an appropriate 1/8" setting.

Try 16.5V and 210 IPM.

[JoshStratton]

Is the welder that he is using that accurate that you can actually tell him an accurate setting to use? What kind is it? I have a cheepo (free) welder that requires adjustments every now and then to get the same burn and will be looking for a new one eventually.

[kamaroman68]

Matt you definitely kick ass. That is absolutely 100% correct. Josh he is recommending those settings because we both own the same welder. It is a miller 251. Again thanks Matt I look forward to talking with you again. Chris

[Matt@RFR]

Josh, like Chris said, he and I are using the same machine. The setting I gave is a guess...it's lower than I would use, but no two guys will like the same setting (depends on stickout, travel angle, wire brand, etc.), and it's also highly dependant on how much voltage you have the machine plugged in to. For example, I'm lucky to have a very consistent 228V coming out of the wall, but you or Chris might have 215V or 232V, and that will change settings.

I used to work at a shop that had a poor electrical system, and I would be changing my setting constantly. We would start work at 7:00, and from 8:00 through lunch, we would lose voltage as every business around us would turn on computers, lights, A/C or heat, etc. I finally gave up...they weren't paying me enough to be that worried about it.

Chris is having problems with his overhead rosette welds falling out. The setting I gave is considereably colder than what he's at now (18V / 245 IPM, right Chris?).

[kamaroman68]

Yes Matt the wire speed and voltage are correct as per your post 18v 240ipm. I will try the lower settings. If I am still unable to do this type of welding I will fly you in for a couple days to do it for me. He he he heh eh eh. No really I planned on building a rotisserie anyways so I can work the bottom of the car and if thats the way I have to go to finish up the welding the thats one more tool I have on my arsenal. Thanks again Matt. Chris