Aircraft TIG welding

[Russ McCutcheon]

I didn?t know there was so much interest in Aircraft TIG welding hear on VAF tell I was trying to learn how to insert a photo in the forums and inserted a couple of weld photos in the test section, I got the help I needed for inserting photos but much to me surprise the photos of the welds drew a lot of attention and some questions.

1. We use W-20 size water cooled torches.
2. Lindy/Heliarc and Lincoln welders, however I have never used a TIG welder that didn?t work well so most anything out there should be pretty good.
3. Very important, we use a gas lens in the torch in place of a gas tip, the lens is a stack of very fine mesh screens that the gas (pure argon) is dispersed through and gives superior shielding over a gas tip. We test every lens we use buy attempting to weld with the electrode sticking out 3/4? past the end of the cup, if the lens fails this test it goes back or in the trash, many fail when new and others work for years and suddenly fail.
4. We use Esab-65 filler rod in 1/16? and 3/32? diameter, we have tried others with mixed results, Lincoln has an equivalent that is a close second to the Esab.
5. We use 1/16? 2% Thoriated tungsten, I am soon going to try some 2% Lanthanated as a substitute, we?ll see how that goes.

We run our torch cables/hoses over head to keep the floor clear and to protect the cables/hoses


We keep the welding machines on the back side of the wall in the back shop so we don't have to listen to them running all day.


Some more weld photos.

[Alschief]

Beautiful work. Very high quality.

[jbagley]

Any reading or classes (pacific northwest?) that you would recommend for those of us contemplating building (or restoring) a tube and fabric airplane?

[Russ McCutcheon]

Originally Posted by Alschief

Beautiful work. Very high quality.

Thanks AL!

[Russ McCutcheon]

Originally Posted by jbagley

Any reading or classes (pacific northwest?) that you would recommend for those of us contemplating building (or restoring) a tube and fabric airplane?

Honestly I don't know, I have hired several people over the years that had gone through the course at Clark College, they had good attitudes but I had to teach them to weld.

[billdianne]

Russ,

Could you give your opinion on TIG vs MIG. In looking at the web site of some LSA makers it seems most are using MIG and their welds don't look anything like yours. Thanks.

[Russ McCutcheon]

Originally Posted by billdianne

Russ,

Could you give your opinion on TIG vs MIG. In looking at the web site of some LSA makers it seems most are using MIG and their welds don't look anything like yours. Thanks.

TIG is superior to MIG and is the accepted electric method for aviation. MIG is what I call fast and dirty and better suited for other things, with that said Kit Fox and others seem to be doing fine with MIG welded structures.

[JanRV6UK]

I have always found aircraft welding very interesting. Something I always have wanted to learn

How do you stress relieve welds that has been done with TIG ? Or is it not considered necessary in the same way as if it was welded with Oxy Acetylene ?

Jan

[Russ McCutcheon]

Originally Posted by JanRV6UK

I have always found aircraft welding very interesting. Something I always have wanted to learn

How do you stress relieve welds that has been done with TIG ? Or is it not considered necessary in the same way as if it was welded with Oxy Acetylene ?

Jan

Hi Jan,
I think your eluding to the fact that Oxy Acetylene welded structures are already stress relived simply buy the nature of the process That process gets everything surrounding the weld red hot,,, not so when TIG welding the same joint.

I’m not an engineer and can’t comment on whether these structures would benefit from stress reliving or not, however none of the parts we build for Van’s call for any further stress reliving of heat treating of any kind so there engineers must see little or no benefit in doing it, at least not on the items we build for them.

[rv9aviator]

I know one manufacturer uses a mig weld to tack the fuselages together but finishes all the welding with tig.
I have done mold repair using tig for over 30 years and your welds really look great.