All MetalShaping

Go Back   All MetalShaping > General Metal Shaping Discussion > Welding Sheet Metal
  Today's Posts Posts for Last 7 Days Posts for Last 14 Days  

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 06-29-2018, 04:20 AM
neilb's Avatar
neilb neilb is offline
MetalShaper of the Month March 2019
 
Join Date: Aug 2013
Location: Melbourne OZ
Posts: 672
Default dc tig mild steel

i'm having a little trouble with my tig, it welds as though there is no gas, the electrode burns up like it would as if the gas was off. i do have gas flow, pre - during - post welding. doesn't matter which type of electrode i use lanthanated, ceriated, zirconated. i have a gas lens fitted, i recently fitted a gas dryer in the feed line in case of moisture. i'm using and have always used argon/co2 mix, i only weld mild steel. machine is a uni mig 200 a/c

anyone have any ideas? i'm about to change to pure argon just to try it
__________________
Neil
Reply With Quote
  #2  
Old 06-29-2018, 04:32 AM
2lateagain 2lateagain is offline
Member
 
Join Date: Jun 2015
Location: Tomerong near Nowra, Australia.
Posts: 10
Default

Have you got the polarity around the right way for TIG, positive to earth.


Graham
__________________
Graham P
Reply With Quote
  #3  
Old 06-29-2018, 04:58 AM
Bevelhead Bevelhead is offline
Member
 
Join Date: Nov 2011
Location: Nelson, New Zealand
Posts: 162
Default

Dead give away for burning back is incorrect polarity. Also check the lens is not contaminated with spatter
__________________
Rick Jones
Reply With Quote
  #4  
Old 06-29-2018, 05:27 AM
neilb's Avatar
neilb neilb is offline
MetalShaper of the Month March 2019
 
Join Date: Aug 2013
Location: Melbourne OZ
Posts: 672
Default

thanks for the quick reply guy's

i can definately say the polarity is correct, i've had this tig about 6 years now and it's only recently it's started to weld like crap lol. i shall check the gas lens and maybe try another. it doesn't get used much to be honest, probably an hour of welding a month at most. so it's hard to pin point when and what, if anything occured when it started going wrong (gas lens fitted, new bottle of gas)
__________________
Neil
Reply With Quote
  #5  
Old 06-29-2018, 06:03 AM
hot rivet hot rivet is offline
Member
 
Join Date: Feb 2012
Location: Gloucester UK
Posts: 265
Default

If you are tig welding steel with anything other than argon you are going to have problems, CO2 is not an inert gas and that will be part of your problem. From experience tig ceramics will absorb moisture and other chemicals even when they appear dry they can outgas whatever it is they absorbed. Poor storage of you torch may have caused the gas pipe to collapse / get pin holes either restricting gas flow or allowing air in. The other very common problem is bad earth due to cable breakage or clamp making poor contact (arced surfaces)
__________________
Paul

Last edited by hot rivet; 06-29-2018 at 06:25 AM.
Reply With Quote
  #6  
Old 06-29-2018, 10:13 AM
mastuart mastuart is offline
Member
 
Join Date: Oct 2016
Location: Mendota Il
Posts: 61
Default

You need argon for tig.
__________________
Mark
Reply With Quote
  #7  
Old 07-02-2018, 03:39 PM
fabricator fabricator is offline
Member
 
Join Date: May 2013
Location: uk
Posts: 58
Default

Quote:
Originally Posted by neilb View Post
i'm having a little trouble with my tig, it welds as though there is no gas, the electrode burns up like it would as if the gas was off. i do have gas flow, pre - during - post welding. doesn't matter which type of electrode i use lanthanated, ceriated, zirconated. i have a gas lens fitted, i recently fitted a gas dryer in the feed line in case of moisture. i'm using and have always used argon/co2 mix, i only weld mild steel. machine is a uni mig 200 a/c

anyone have any ideas? i'm about to change to pure argon just to try it
Neil, I tried this today on 16G mild steel sheet, all scale removed, and wiped down with Acetone.
Pure argon , near perfect welds, no problem at all, changed over to argon/ co2 mig gas, not good , tiny bubbles ,craters ,and the tungsten picking up cr@p.In my opinion , for what it's worth, mixed gas doesn't work for me either.
Just another thought, I Scotchbrite the copper coating off my filler rods, then wipe down, this seems to stop the bubbles anyway.
Cheers,
Fab.
__________________
Neil

Share what you know, learn what you don't.

Last edited by fabricator; 07-02-2018 at 03:50 PM.
Reply With Quote
  #8  
Old 07-02-2018, 05:28 PM
ozcad ozcad is offline
Member
 
Join Date: Apr 2017
Location: Bonbeach Australia
Posts: 29
Default

I don't know who's brand of gas you are using but I have changed over from rental bottles to owning my own and couldn't be happier. An E size argon from Pacific Gas (no affiliation, just happy customer) is $220 outright and $80 for refill.
__________________
Peter
Reply With Quote
  #9  
Old 07-02-2018, 10:56 PM
Rod S. Rod S. is offline
Member
 
Join Date: Feb 2010
Location: Strasburg Colorado
Posts: 36
Default Wrong Gas

I have been a welder repair tech for 21years. WRONG GAS Pure argon Pure argon Pure argon for mild steel..... I have heard many guys tell me they have always used a mix ar/co2 for tig and they are wrong.....
Reply With Quote
  #10  
Old 07-03-2018, 07:23 AM
Oldnek Oldnek is offline
Member
 
Join Date: Mar 2011
Location: Ulladulla, Australia
Posts: 1,346
Default

Quote:
Originally Posted by ozcad View Post
I don't know who's brand of gas you are using but I have changed over from rental bottles to owning my own and couldn't be happier. An E size argon from Pacific Gas (no affiliation, just happy customer) is $220 outright and $80 for refill.
G Day Peter,
Definitely owning your bottles is the way to go. Over the last 7 years I have saved myself over $3200 in rentals.
Your gas seems very cheap, with that price, that's not for a D Size bottle by any chance.
I use Speedgas and there price is $445 outright and $145 Refill for the E Size.
G Argon refill is $175.
Cant wait till they do the Oxy/Accet bottles.
__________________
John
EK Holden V8
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -5. The time now is 06:06 AM.

Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.