Hi, i just recently purchased a new lincoln 255 mig.

Im welding 3" stainless exhaust pipe, Im using a 0.023 stainess wire, and apporpriate gas, the gas is set at 25psi.

The tips im using are for 0.030 wire.

Now, in the past i have used my old welder to weld mild steel flawless, it was a old esab 200 unit. I had been using it for years ever since i started to weld (its my dads machine)

Now, with the new machine, set up with 0.035 wire, welding mild steel with a different gas, it works great.

When i switch to stainless, as soon as i pull the trigger, the wire hits the piece and melts away usually sticking to the tip, this gets really annoying and makes it hard to weld.

When i do get it started (have to start it furthur away and move in once its going) It appears to be almost dripping off, and it isnt smooth, its really bouncing around on me.

Now, my question is, i know this is a big machine for such a small wire, but could my oversized tips be the problem? The wire does slop around a considerable amount.

Normally when i weld thin walled pipe, i usually do a series of short welds to keep the heat down, but its not working out for me too well at this point.

Ill give it another try tommorow.

So is my problem the tips, or do i have the welder set up entierly wrong for stainless, is my wire speed too fast/slow, and as well for the voltage.

Im sorry if this is in the wrong section, mods feel free to move it accordingly

TYIA ALL!

 

AFAIK, the wire is 'energized' at the tip which makes me think you need to get the right size tip and try again. The wire won't necessarily being making contact with the tip at all times so you wont be able to weld smoothly.

You say you have to start further away. Are you advancing the wire further then you normally would, say far enough so it could bend and touch the tip?

On another note, where abouts did you pick up the welder from? I'm in Stoney Creek and looking to get my hands on a similar machine.

 

AFAIK, the wire is 'energized' at the tip which makes me think you need to get the right size tip and try again. The wire won't necessarily being making contact with the tip at all times so you wont be able to weld smoothly.

- Yes, because when i do get it going, its welding great etc, then all of a sudden. bam it just blows away and stops..? (maybe it looses contact for a second) Does the wire need to be in contact with the tip at all times for it to work properly?


You say you have to start further away. Are you advancing the wire further then you normally would, say far enough so it could bend and touch the tip?

Yes, far enough it could bend and touch, the wire bends very easily.. So this makes perfect sence.


On another note, where abouts did you pick up the welder from? I'm in Stoney Creek and looking to get my hands on a similar machine.

I got it at praxair, down on grays road in stoney creek, right before the tracks, its on the left hand side. If a Miller machine suits your fancy they have all sorts of them as well!


Thanks alot, ill stop by princess auto tommorow on my way home from work and pick up some proper size tips! And some fuel hose so i can get that tank back up

 

To me it sounds like your wire speed might be a little slow or the amps are too high.

Do you have a piece of stock to run some practice beads on? You can tune the amps and speed there.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by StanBo &raquo;</TD></TR><TR><TD CLASS="quote">To me it sounds like your wire speed might be a little slow or the amps are too high.

Do you have a piece of stock to run some practice beads on? You can tune the amps and speed there. </TD></TR></TABLE>

Thanks, my dads welder guy is comming over tonight, hes going to help me set it and fine tune it

 

Cool post up your findings. I haven't migged since class and that is almost a year ago now.

 

Oh yes, and it turns out the tips the guy gave me were 0.035 - 9mm. Not 0.023 - 6mm like i needed.

But ill see what happens.

 

.035 is .889 mm

get the proper tip, and take some pics of your work...
then let me see that exhaust

 

Well..

I have come to the conclusion..

Lincoln SUCKS!

The welder guy spent like 2 hours tweaking it to no avail, right size tips, rollers, tension etc.

So i got fed up, and put my gas and wire in my old esab smaller machine, and went to town with that.. Its very hard to weld thin wall pipe with mig, since you cant adjust the heat as you go. I have it set fairly hot, and i just tack it all around. Then just do fairly large tack welds, 2 beside eachother. To form a bead all the way around.. Penetration looks good from the inside, and discolouation is even. Then i grind down the weld and leave it just sticking up a small amount (for strenght).

Im an by no means a pro welder, but the inside is super smooth, and the overall design of the downpipe/exhaust is good (IMO)

Ill get pics of the downpipe/exhaust etc once im finished! Should be in a few days hopefully minus muffler (still waiting on it)

So about my welder i spent around 3K on (cnd) in welder + accessories. Im going to call the manufacture on monday and see whats up, the damn things only 3 weeks old.. Ill likely return it and pick up a miller machine.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dfoxengr &raquo;</TD></TR><TR><TD CLASS="quote">
then let me see that exhaust</TD></TR></TABLE>

Oh yes, its already fitted. it fit good, but the slip fit was NFG, it was too tight, and since my exhaust expander only goes to 2.5" I had to get out the torch, heat up the expanded part, and slide in the other piece.

Only advantage to this is it made mock up very easy since the exhaust didnt turn once it was together

 

coo

 

Your problem was definetly the tips. I stopped reading right after you said that. There's a reason they have different sizes!

After that, you just need to figure out for yourself what settings work best. That's what scrap metal is for.

 

I sure hope so man, tips should be in monday for the time ive been using my old esab, working great.. downpipe is done and gas tank is back up and 3" exhaust is fitted..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by StanBo &raquo;</TD></TR><TR><TD CLASS="quote">To me it sounds like your wire speed might be a little slow or the amps are too high.
</TD></TR></TABLE>

These are not two separate variables when mig welding, wire speed controls amperage directly and voltage is set to accommodate whatever wire speed you happen to need.