welding rod choice

[airman]

any suggestions on the best welding rod to use? I am gas welding my fuselage.

[Dan_]

any suggestions on the best welding rod to use? I am gas welding my fuselage.

• RG-45
• RG-60
• ER-70S2

Yes the 45 is the least tensile but it flows well.  

The bead is many, many times thicker than the tubing so tensile strength has no bearing on deciding between these 3...

http://bcove.me/x0gcwqy2

[sonicapollo]

ER70S6 recommended by tinmantech.

[subnoize]

I would stick (pun intended) with the ER70S6. It may not flow as well as other but its sparks less and there seems to be a consensus among the aircraft 4130 guys that gives good results.

I have had great luck with these polished, copper free rods; Amazon Store TIG Rods ER70S6

They are a great price and Amazon sells a lot of them so when its in stock, buy two.

I would store these rods in a climate controlled room and they should not corrode. I "lost" a 10 pound tube in a bad place and when I found them I was shocked that they were still usable. The polishing technique they use is pretty cool. They are Italian and that is where I had heard about them. I fly Italian made planes at a dealership and the welders in the shop were like, "hey, try these. you will never go back."

I am still using them and will build my DE with them :-)


--jb

[Tom XL-7]

That is a good price. I hope not to put 10 pounds of rod into a 35 pound fuselage though and I don't know what else to use it on.   Most of my welding is mild steel, for me the rg-45 works well on my projects. I can get it for about 1.99 a pound. The rg-60 kicks up to about $5/ #.  I haven't thought about the rod causing sparks. I have always assumed it was me screwing up as in too much oxy, too close, or  not cleaning stuff thoroughly. Next time I get a hot spark down my shirt (gas welding does not require as much protection. For me a #5 facesheild )  I will  swear at the rod and not solve the issue.   When I think of a fuselage it is the buckling or bending issue of long unsupported tubes (that's a midpoint thing) that concerns me not the welds.  I may wind up with a weld twice as thick as that paper thin tube, in tight clusters  probably too thick, so I am not worried about ultimate stregnth of the rod. Hopefully I won't find out the hard way that I am wrong.
 It is very important to make sure you are melting the parent metal and not just applying a bead. that is the criticism of mig welding and amateur welders. You can see into the weld, see the edges. and it is time to add rod too cool that puddle down. Watch it long enough and you will see a hole. And that happens. I think a good weld is the bigger concern over  choice of rod. Also pretty is nice but ugly can be strong.   It is easy to get wrapped up in the appearance , try to keep things consistent but always make sure both parent metals are fused together. The rod is for reinforcement , puddle control, and keeps welds from being starved-concave. 
 You should pick the rod you are comfortable with. The world is clearly moving towards tig and tig rods, so that can't be a bad choice. Some of us are just hanging on to what we are familiar with. 
Tom XL-7

[subnoize]

 I hope not to put 10 pounds of rod into a 35 pound fuselage though and I don't know what else to use it on. 

What? You're not building two planes?

I have a Sonerai IILS finishing up and I am making room for the DE. Somebody purchased the Sonerai from me (an offer I couldn't refuse) and now I am starting what was going to be my pattern/patch plane, the DE. I am a software guy by day so there is something therapeutic about building and welding things. With 10 pounds I was building all sorts of cool tools and tables and stuff and ran out before I even started my first plane. It's better that duct tape and super glue combined!

--jb

[boba65$#]

As a long-time retired A&P , Ive used rg45 as the standard for fuselage welds with tremendous success(definition: never a failure/random destructive testing ALWAYS tore the tube and NOT the weld). With cleanliness,LOTS OF PRACTICE, and the proper equiptment( In my case, the MECO-MIDGET and lightweight hoses).......The latest and greatest is great, but it aint no shortcut to PROPER technique. I own MIG/TIG/Plasma cutters/sticc boxes, etc......but love the gas weld. Rebuilt lots of cubs that sat in barn for 30 years with rats nests on every weld joint.....and they were welded by people with 6 hrs of instruction(on the average). MOST of them  passed NDT stress testing, and critical x-rays insp. Not knocking the "new stuff",but as somebody mentioned....its kinda going that way. Every year, I get an elk, and when I draw a tag, a Moose... with my dads ww2 8mm Mauser, and they never complained about the effectiveness of using "old" school stuff! take care amigos!