First Tube Tig Welds Today

By jimmyjeep Date 04-03-2008 02:33

After 600 hrs. of weld school, I finally got to tig weld my first tubing today. Did you know there are no flat spots on tubing! LOL Anyway I took a 1 1/16" ms tube in, cut it into 3" pcs and rewelded it back into one pc. Theres definately a learning curve. My questions for you guys that do rollbars, cages and dunebuggys are how many tacks do you try to get onto a tube before you go around it? Do you weld up to the tack or pass over it? Do you skip around the tube or just go around it in a circle effort? My first efforts were a disaster but its getting better by the weld so I'm pretty happy at this point. If I can tig it, I know I can mig it.

By Scott Hutchison Date 05-09-2008 04:20

according tp the AWS "fusion welding for aerospace applications" manual, four tack welds are acceptable but must be blended on final pass. I'm a bit of a newb but that's what it says. Good luck.

By Tommyjoking (****)

Date 05-09-2008 09:38

you did not mention thickness or position but.....

On a tube that size I would use four tacks....go 180 deg as I tack. If it was a 5g or a 6g position I will do it in two welds (typically on thin tubing) I will start at 6 o-clock on both sides and end at 30 minutes passed the 12 o-clock mark from each direction. I allow a bit of cooling time on small tubes in aluminum between passes. I do this left and right handed if there is no way to reposition myself or the weldment. If I can fit myself around it I do it all right handed. Anything smaller then 3/4" I will only put three 120 degree spaced tacks with the first being at 6 0-clock. 2" and up I may use 6 or more tacks depending on the thickness....how much of a groove vs gap and draw I may have. If this is 5g and you are allowed to roll it....then weld as far as you can reach and repeat...just make sure you overlap each pass.

Biggest tip I can give you without being there is ......practice, and pick...your torch and hand movements before you ever strike an arc. Pick your grip and rotate your torch around the pipe seeing what your angles are in regards to being perpendicular to the joint, visualize your gas coverage and where your rod will be in it (do not remove your rod from that gas coverage). Practice going around the joint dry with no arc first and this will do wonders for you when you weld it.

Good Luck and regards
Tommy

By ravi theCobra (**)

Date 05-10-2008 00:09

Was it 1 1/16 od tubing or 3/4" pipe which is 1.050 OD ?

Makes a difference -