Thread: Tig welding inside a small tube ?

I have a issue I need to repair or pay to have done.

I am wondering if it is feasable to buy a 90 degree small torch to repair an area inside a 2.5 od SS tube that is approx. 3 inches deep into the tube. Tube wall is .060.

I don't have the unit apart for pics yet. It is a SS header off a Drag Race engine, there is a burn through or "sugar" spot in the tube that will allow liquid to leak through and drip out through the outer sleeve.

I am thinking I can get in there and grind down the sugar spot and then with a small torch get to it and weld up the spot.

I have a synchrowave 250 here at home. I guess I am looking for places to buy a torch small enough or would take them to a shop somehwere in Calif ???

Thanks

This is the torch I used to weld some wishbones into a fuel probe for F16 drop tanks a few years ago.

Flexible-Neck Hand-Held Air-Cooled TIG Torches - WP 24 Series by Weldcraft

What torch do you have water or air cooled? you can get very short caps for the tungston. Also on the water cooled torches you can get a fairly small gas lens. With a small cap and the gas lens your stack up should be about 1.25"

Could you backpurge the header with argon using a second regulator or splitting your primary and using valves, do the weld on the outside of the tube and then grind the inside till its ok?

Originally Posted by greenbuggy

Could you backpurge the header with argon using a second regulator or splitting your primary and using valves, do the weld on the outside of the tube and then grind the inside till its ok?

No I can't because the outside of the tube where it's was welded is now covered with a sleeve of larger tubing to provide some resistance to causing fires when covered in oil-------------

Originally Posted by Whetstone

What torch do you have water or air cooled? you can get very short caps for the tungston. Also on the water cooled torches you can get a fairly small gas lens. With a small cap and the gas lens your stack up should be about 1.25"

I have a WP 20 with a water cooled Sync 250 machine -- I will look up the parts, that might get me in there

You may be able to get in there with a wp20 with a short backcap and a small non gas lense cup.

The WP24 torch I used is the W watercooled version good to 180 amps, it loads from the front there is no
backcap

Howdy,

If the torch you have won't fit, one of these most definitely will. They have glass shielding cups for improved visibility. I know other makers have this style as well.

Micro TIG Torch

Let us know how it turns out!

Kind Regards,

dgcope

Originally Posted by Mark Leigh

I have a WP 20 with a water cooled Sync 250 machine -- I will look up the parts, that might get me in there

The C-K flex loc #20, water cooled, 250 amp with silicone jacketed leads costs...but you'll find
it usable for lots of other items. Very comfortable, very ergometric.

Picture shows #7 gas lens, AC on AL, the head unlocks and swivels.

My only comment is that I sure want to see a pic of the weld you need to make. My eyes aren't that good anymore... hope it works out for you.
Once you remove the part can you weld from one side and look from the other?
The 24 series torches look like the ticket, though.

I am going to have to weld and use the filler rod through the same tube opening and try to get a good look at it too !

If all else fails if your dead careful and don't mind a ugly result stick welding it is border line possible in 1.5mm in my experience! I frigging hate doing it, but when the chips are down that is always one option. Its so much easier to get in there with only one electrode!

I think Dave nailed it. Here's a video of the CK World Wide flex loc:



Water Cooled Tig Torch

Originally Posted by dave powelson

The C-K flex loc #20, water cooled, 250 amp with silicone jacketed leads costs...but you'll find
it usable for lots of other items. Very comfortable, very ergometric.

Picture shows #7 gas lens, AC on AL, the head unlocks and swivels.

I really like that torch Dave, but will it fit in a 2.375 opening about 3 inches inside ?

Originally Posted by Mark Leigh

I really like that torch Dave, but will it fit in a 2.375 opening about 3 inches inside ?

Looks like it might just tweak in there. Look at the video I posted. That box tube kinda looks like 3''.

Do the odd collector, using a CK water cooled micro tig torch, much like the TEC one linked up above, managed to get inside a 2" tube comfortably - and even smaller ports.

Supposedly rated for 140amp, although I've managed to turn the head and collet into a molten mess doing a port for what I consider, a relatively short duration. Consumables are ridiculously priced I will mention.....and if anyone knows a cheap source for the pyrex nozzles, I'm all ears.

Originally Posted by Mark Leigh

I really like that torch Dave, but will it fit in a 2.375 opening about 3 inches inside ?

I'll need to measure the torch head o/a/l including tungsten stickout and cap--tomorrow, then post the length.

This is my primary tig torch setup, for daily use.
The head swivel eventually wears out, needing replacement at a price.
I'm on my fourth head and 3rd torch lead set in 13 years, using this flex-loc.
The swivel head restricts coolant flow some, had to jack up cooler pressure to 60 psi
to get adequate flow return back into cooler.

The head can be moved quickly, to get a better attitude-which to me is worth much, plus
being able to comfortably push or pull, run right or left hand and in crazy out of position attitudes.
[I've tracked myself on how many head adjustments I may make during a weld routine,
realizing with the fixed head torch, it's the weldor that has to adjust or contort--not the torch]

(Photo is of plug welds inside PT-19 AL air intake box for a primary trainer that was being rebuilt
and completely restored to flight status by A&P shop with IA.)

I'm a big fan of pulsing on SS, but that's another topic.

O/A/L from top of shortest cap to front of #7 gas lens cup is 2.200.
This is too tight a fit, doesn't allow for tungsten stickout.

The #20 gas lens cups are all the same height, regardless of opening size.

The 'standard' cups and collet bodies have an assembled O/A/L of 2.500+ in the flex-loc,
with the shortest cap.

Thanks for the leg work Dave, I will pull the car out of the trailer this weekend and pull the headers off, I will update next week on my plan . Thanks again I was hoping that torch would fit as I would like to have one anyway !

maybe a wt-24 tourch could work WeldTec® Water Cooled TIG Torches i have the flex head that i use when i have a tight spot on a roll cage. my standard set up is 1.250" with tungsten stick out