burning holes in chromoly tubing

Deadmau5 · Fri Apr 10, 2015 2:46 am

Hi Guys,

I'm a bit of a beginner at tig welding. I've done some mild steel work and made some gates etc but have a few other projects id like to attempt. one of them is a bike frame. I've been doing some practice on some what i think is thin wall chromoly tubing (off cuts from bike frame tube set i purchased) and as soon as i get near the edge of the tubing it burns a hole even on low amps. i dont seem to have an issue when welding in the middle of the tubing

can anyone give me some pointers on how i can prevent this.

zank · Fri Apr 10, 2015 7:30 am

You need to get a good sized puddle going. The added mass of metal helps control the edges of the tubes.

zank · Fri Apr 10, 2015 7:30 am

And welcome to the forum!

Mike · Fri Apr 10, 2015 7:36 am

Welcome to the forum.

Graveyard · Fri Apr 10, 2015 12:02 pm

What Amperage are you using?

dirtmidget33 · Fri Apr 10, 2015 1:27 pm

Yep what amperage and what is wall thickness of tubing? is this I fillet weld where you are joining two coped pieces together? Do you burn a hole as soon as arc starts? If so does machine have a hot start adjustment? What machine you using? Size of filler rod and type?

I know we got a lot of questions but more details we have better we can guide you in right direction without wasting your time and materials.

motox · Fri Apr 10, 2015 2:18 pm

how close it the fit up
one more added question
craig

exnailpounder · Fri Apr 10, 2015 2:34 pm

Where were you on Dec 7th 2012 at 4:15 pm! Sorry

Couldn't help myself...off early today and stopped for a few...Welcome to the forum/amusement park

Deadmau5 · Fri Apr 10, 2015 6:44 pm

So many questions? I'll check all my settings but it's a 200amp tig inverter and currently the piece i was practicing on wasn't fitted up to another tube it was just a tube to practice on.

I'll check out all the other details and get back to you. I appreciate the help

Fri Apr 10, 2015 6:46 pm

exnailpounder wrote:Where were you on Dec 7th 2012 at 4:15 pm! Sorry Couldn't help myself...off early today and stopped for a few...Welcome to the forum/amusement park

Dec. 7 2012? I was in a Karaoke bar attacking a Pearl Bailey impersonator.

...think about it

Steve S

Fri Apr 10, 2015 6:51 pm

Deadmau5 wrote:So many questions? I'll check all my settings but it's a 200amp tig inverter and currently the piece i was practicing on wasn't fitted up to another tube it was just a tube to practice on.

I'll check out all the other details and get back to you. I appreciate the help

There's your problem...

You're welding on the side of a tube, and when you reach the end, there's nowhere for the heat to go. Welding a joint is a different matter. You have two tubes meeting, and plenty of metal to carry the heat away.

To weld practice to the end of the tube, you'll need to tail off your power a LOT as you approach the edge, and add metal often, to keep the puddle cool.

Steve S

TRACKRANGER · Fri Apr 10, 2015 7:06 pm

Otto Nobedder wrote:
Dec. 7 2012? I was in a Karaoke bar attacking a Pearl Bailey impersonator.

Give or take a few years...