Hatz Biplane Association

I don't mean to spread uncertainty doubt and fear, but this is verbatim from the Tinmantech, a craftsman and expert on all things aircraft welding and the seller of my Meco Midget welding torch [url]https://www.tinmantech.com/products/welding/flux-filler-metals/4130-Steel-filler.php[/url]:
"Our filler rod for 4130 Chrome Moly is NOT 4130 alloy. Rather, we offer what engineers, welders, and experience shows to be the best choice for welding structures of tubing and sheet: ER70S6"

The difference between -S2 and -S6? subtle:
[url]http://www.weldingtipsandtricks.com/er70s2-er70s6.html[/url]

Stay calm and weld on.

Just right! The reason I asked is that aircraft welding is kind of special. At work, we give out work to a tool and die welding shop. When I asked him what he would use to weld 4130 tubing, his answer was 4130. We know that we want a ductile weld, so the er70-s2 is perfect. Just think how much better your welds will get as you gain practice! I think it will be easier, not better.

Thanks for the input. I am lucky enough to have a good teacher. I feel somewhat confident with my welds but he’s never done a fuselage so I thought I might get some critique of my samples from guys in the know.
Rod is ER70-S2 ,1/16th Thoriated tungsten
The guy teaching me is aerospace certified and has some connections in the testing world. We will send some coupons out to be magnafluxed looked at for the general parameters.
Again, thanks for taking the time.
Doug

It looks like you are not new to welding. From the pictures your work is excellent. No undercutting and good penetration. Metal was cleaned prior to welding. If those parts are trials on scrap, cut through a weld to see if there is any porosity. Take a thin section and try to break it. What rod are you using?
Al

When I started my first homebuilt in the early '70's I took some of my first welded fittings over to an experienced welders house to have him look at them. He happened to be welding at the time so I watched for a while, quietly left, and
went home and deposited my stuff in the trash can and started over. A good idea would be to have someone with some experience watch while you are doing some practice welding. I was told that the only person that can judge the quality of a weld is the guy doing the welding.
John Hanson

New at clusters. Would appreciate some critiquing from those that have TIG’ed before.