Hatz Biplane Association

I haven't worked since 10/5 as I decided to winterize the garage and take care of other business. I'll be finishing rib construction in the house. So, I'm getting geared up for welding the fuselage. I'm torn between TIG and gas. I've read a lot and can't make up my mind. For working in my garage, I prefer a TIG set up and I'm leaning that way. EAA has welding workshops coming up Jan and Feb, but they're gas. Which method did you use and why? Anything you'd do differently? Thanks!

I use gas because I'm the type who can't rub my head and pat my belly at the same time. Pushing a gas pedal, guiding a flame front and dabbing a welding rod all at the same time reminds me of flying a helicopter. And, you can't let go of anything to scratch your nose. Gas is easier for me, probably because I've had very little tig instruction. I'm not in a hurry, which is an advantage of tig. And when gas welding, the issue of stress relieving is easily addressed during the welding process since the HAZ is not so concentrated in a small area. And the set up for gas welding is not nearly as expensive as a tig set up.

There's pros and cons...just some of my thoughts...

Hi,
I didn't weld the fuselage of my Hatz, it is a Weld-Tech, but I did the welding on a prior plane 20+ years ago. I used TIG mostly because it was available. I did sample gas on a cluster or two which convinced me that TIG was much faster and easier for me. Tacking with TIG did not involve much heat, so my jig board did not need protection from the torch heat. I did use a gas torch to normalize the TIG welds after they were complete. I have since received a Henrob torch as a gift and find it makes welding tubes quite easy compared to the Airco that I tried years ago. If I did not have a TIG machine, I would definitely use gas.
Al

I chose gas because it was cheaper to get set up with and more forgiving for a new guy. Now that I've used it I would probably move to TIG next time. However, if you are going to use TIG for your first welding experience, make sure you can achieve very good fits when cutting your tubing... especially on the clusters. As others have said, TIG has a much smaller HAZ which means you have a smaller area affected buy the heat, but this also means that you have to have a tight fit with your tubing within the HAZ. If you feel that you can cut/grind your tubing joints such that you can get a nice tight fit, then go ahead with TIG. You might want to experiment first.

Thanks for all the comments. It would be an easier decision if I could try both methods somewhere, but there's no schools around here and I don't know anybody with welding equipment. Perhaps I'll buy the bare and cheap basics of gas or TIG...just enough to test it, and then see which I like.

Here is how it was explained to me by an old-timer.

1) Using a TIG requires much closer tolerances when cutting and fitting tubes.
2) the TIG weld is likely more attractive in the end.
3) The TIG creates heat very close to the weld and therefore sets up major stresses near the cluster. because of this, the whole cluster, when done, needs to be heated and normalized with one (maybe two) OA torches. So even if you have a TIG, you're going to need OA anyway.
4) OA fill bigger gaps easier. Construction is likely to go ahead much more quickly.

With these in mind, carry on and make up your own mind. But do not forget to normalize the clusters after they're finish welded.

Good Luck!

Nick

Thanks...I'll go with the gas and try to get to the EAA workshop in February. Thanks again everyone.

I did an EAA workshop to get myself started with welding and it was worth every penny! Had a great time, learned the basics, and got a sun (UV) burn on my face all in the same weekend! I couldn't wait to get home and start practicing what I'd learned. And I'd recommend the Micco Midget torch/lightweight hose from the Tinman.

Thanks. I've watched the tin man video (old VHS tapes), and download all I could find at EAA, as well as a few books. I've also been looking at this page at the tim man site:
https://www.tinmantech.com/html/kits_4130.php

I'll wait for the workshop, then go shopping. Maybe it'll make a nice getaway for me and my wife, hmmmm.

I want to buy R-45 filler rod for OA welding. I looked at AS&S and Wicks, but everything seems to be TIG. I can't even find the ID R-45. Where can I buy it or is it called something else now? Thanks!