thin walled tubing??

[johnakay]

you would of though that I should know this by now after nearly 40 years off welding etc.
also I'm not the best of welders but I've always got by.
for some reason these day my mind seem to draw a blank as to why and what nots etc.
I can't seem to get a decent welds on thin walled tubing.
I seem to get a rather heavy weld build up even though I have the setting right and speed movement.
I've even had the setting lower but it appears the weld looked cold and not enough penetration.
wall thickness 1.5mm x 19mm,16mm and 12mm tubings.
I'm currently using .8mm wire with argon mix.
I want to put a thin bead of weld on the tube.
most of my welding is on 1.5mm to 3mm max with the odd 4mm or 5mm but rare.
I'm thinking now that perhaps I'd be better off using .6mm wire rather than .8mm.
I wouldn't mind if I can get welds like these in the picture below(not mine), Iknow its much thicker tubing I know.

 

[the snooper]

the welds in the pictures below are stop starts, have you tried slowing down the wire feed

 

[BrokenBiker]

turn the wire feed down a notch, let the puddle get nice and hot and it should sink in a bit better whilst not building up as much. The pic looks like stitch welding. Which is how i do anything thin, but 1.5mm should be able to weld a continuous bead without blowing through if the settings are right

 

[F.J.]

Don't weave either, just let the puddle form and push in a line rather than going from side to side. You wont be able to do a very long run on the diameter you are welding mind

 

[chevy2]

I'd prefer to use 0.6mm mig wire on that wall thickness tubing,
it would be more controllable on the lower amperage needed and you'd be able to produce the lower sized weld you're aiming for.

 

[BrokenBiker]

I'd prefer to use 0.6mm mig wire on that wall thickness tubing,
it would be more controllable on the lower amperage needed and you'd be able to produce the lower sized weld you're aiming for.

i missed this bit, for some reason i assumed you were using .6 wire.

 

[johnakay]

I've tried slowing the wire speed but does not work just spits as if burning back etc, even turn the amps down and wire speed equally but finish up with weld appeared not penetrating.
I've got all the setting right.I'll try the .6mm when I run out of the .8mm wire.
the problem is mainly on the 2 tubing itself.
19mm drilled out to 12.5mm for fitment of 12mm tubing,that is where the problem lies.
most thin tubing welding what I can find is tig welded and not mig such as U tube
I'll take some pictures that'll give you an idea..
thanks for replying. john

 

[F.J.]

I build these bikes from the ground up from 1.5mm and 1.2mm walled tube. Depending which weld it is depends if I stop/start or stitch weld it. The tube sizes are 1 3/4" and 1 1/8" and I use 0.8mm wire on a 200 amp welder. I cant say what amperage I use but I either use setting 3 or 4 of 7. Hope this helps

 

[AndyStobbs]

You'll get it sussed. You're doing well to not be blowing holes, rarely read of someone failing to get good pen on thin stuff.