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Discussion Starter #1
I'm the proud owner of a $200 wirefeed mig with gas hook up.

i've goten ok at welding with it, i invented my own technique though.

the only thing that i can't seem to get happening is overhead welds.

they don't stick. (why am i typing like Hack? pardon my double spacing).

the weld doesn't seem to want to stick to the metal and make that noise that i've been hearing when welding from above (very quick zapzapzap noise).
So i'm looking for some tips since i've got to weld some brackets on my xs and i don't want to remove the motor and flip the frame upside down and make my welds. everything i've read said that its just a little more nerve racking, but i can't even get the damn melted wire to stick no matter how clean the metal is. its almost like gravity is letting the puddle drip off the part and its just landing in the end of my gun or on to my fucking shirts causing me to look like i haven't bought new clothes in 15 years.
tips?
 

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you may be running it a bit hot just play around with you heat and wire speed, and try moving you hand a bit faster as you go, sometimes its just a matter of getting the right motion, as in push or pull or doing little swirls,overhead is never easy and when ever possible flip it over,
 

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Keep typing like me and flip the bike to make your welds

my guess is for overhead welds to be easy you probably need a different gas mix for starters

probably a mix that has helium or nitro in it if I had to guess



just yet another reason why tig rules
 

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You don't have the polarity reversed on the welder do you?

Check it...it goes one way for flux core wire (often), goes the other way for gas shielded welding.

Off the top of my head I think it should be electrode negative for gas shielded, and electrode positive for flux core.

I've got two MIGs, one gas, one flux, so I never really change them and forget which way is which.
JohnnyB
 

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What Branson said although I think he's got it backwards. I'll look at my welder when I go back to the shop tonight.

Run a little cooler, hold the gun off to the side a little so the wire flows from the frame to the bracket.

I only weld upside down if I absolutely have to especially if it's structural, double especially if it needs to be pretty. Back in the old days I'd flip race car chassis over in the shop to weld off the underside. I think you'll find is that it's easier to get things in a position that works for you than it is to fight it.
 

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My major weakness as a welder is my hatred of "out of position" welding. I too absolutely prefer having something in the right place, easy to get to, easy to concentrate on a good weld.
JohnnyB
 

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Discussion Starter #8
why isn't it binding up when gun is facing down?
i practiced a little more last night. every once in a while it would stick and if i went slow i could keep the puddle going. but still, it was more common for the bead to not start and just look shity.
 

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Looked at my welder. For MIG its negative ground, positive to the gun.

Not saying this is what's happening, but you will notice if you do get the gun all wadded around the wire won't feed as smooth. Wire can get shitty if it's humid in your shop and that screws up the feed. I only run 10 lb. rolls for that reason, Iowa summers are ungodly humid.

Trying to explain my technique better; If you hold the nozzle pointed straight up all the wire does is burn back and plug the tip. Get the gun in a position to be as close to horizontal as possible. Normally you run a little cooler, sometimes to get the gun in a usable position you may have to run a little hotter(and turn up the gas) because you're welding so far from the tip. Start on the topside material, let the wire puddle down.

Here again I'm gonna tell ya I've turned some BIG pieces upside down to weld them. A bike frame wouldn't even be a question to me that I would. If you only have to take the motor out because of splatter get some good aerosol anti-splatter and spray it, or they make welding blankets, or if you're cheap like me get your cloth shop towels soaking wet and cover it up with them.

Anyone else notice we're all starting to type like Hack?
 

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my aging eyes really appreciate it

makes all of your writing much more interesting
 

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I've welded with good mig machines and shitty ones as well.

The better the machine, the easier it is to up weld. But like the other guy said, I rarely do up welds because it is difficult to get the position right, which leads to shitty welds with poor penetration.

On nice, 220v machines, this is less of an issue.

--chris
 

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Your shielding gas is falling away (heavier than air) and you are oxidizing at the arc enough to blow the weld. Does it look like you spooned dog-poo into the joint? My high school welding teach told me to raise the gas pressure and flood the working area. Uses a queens-metric-buttload of gas that way. As has been stated....turn the work piece over if you can.
 
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