Oxy-Acetylene Welding Torch set-up

[Yard Sale]

What torch and tip(s) do you use for welding up the fuselage? O2 Pressure? Acetylene Pressure?

I'm not a welder, but I intend to build a Bearhawk from plans anyhow. As such, I have a serious need to learn how to weld.
I realize I'm not going to become an expert welder overnight, but I need to get a torch so I can start practicing and learning how to weld.

I've looked at the Cobra/Dillon/Henrob/DHC-2000 Torch, the Meco Midget Torch, and the standard Victor torch. I want to buy a good quality torch that will be useful for many, many years.

To be honest, I'm leaning towards the Cobra torch. I like that it can be used to weld all kinds of metal, including Aluminum, and that it's capable of cutting metal similar to a plasma cutter.

The thing I'm not too sure about is the weight of the torch and the unusual shape. But, since I'm not a welder and don't have any experience with O-A torches, I don't think I will have any more of a difficult time learning to how to use this one vs the conventional looking torches because I'm not used to any particular feel yet.

Also, is welding 4130 steel tube much different than welding standard/mild steel plate as far as technique? The reason I'm asking is that I figure I'm going to need LOTS of practice to be good enough to weld the fuselage together with any confidence that it won't catastrophically fail in midair. I'm assuming mild steel is cheaper and more plentiful to find/purchase than 4130 and I don't want to spend an arm and a leg making scrap and learning how to weld if I don't have to.

[Chris In Milwaukee]

I have the Meco, myself. I love its weight and balance, and it can be used to weld both steel and aluminum. I plan to try to weld up my fuel tanks with it with the guidance of Kent-master's aluminum welding videos. Thankfully I have AviPro as a backup, just in case

~Chris

[Roy Glenn]

I use about 5 lbs on both O2 And Acetylene, For 4130 w/ Henrob #2 tip and with Victor #6 tip as numbers vary with different MFG. Mild steel is good for Practice ,But is a lot easier to weld than 4130

Roy
Bearhawk 274 & LSA 002

[Mark Moyle]

That cobra torch looks cool. Bit large. My primary welder is a TIG torch, second for the tight areas is the torch from TM Technologies (Kent Master). Best small torch I've used. Lays flat on the table when lit. My other torch is the full size victor torch. Pain in the butt to set aside lit when you need two hands. Kent's instructional videos are wonderful. As to practicing. I was fist taught how in high school shop class. The teacher set us up with one inch wide' 1/8" thick, 4" long pieces of mild steel flat bar. Kent's torch set tips are large enough for steel 1/8" thick. Steel coat hangers make for good filler rod. Once you obtain the torch and steel and have practiced. Come back and ask us questions here. Mark M. Sent from my iPad using Tapatalk HD

[Mark Moyle]

What I forgot to add. Start practicing with butt welds no filler. Grind the radius off the edge of the flat bar pieces to be welded together....no gaps. This'll teach you the puddle/penetration and tip control. Sent from my iPad using Tapatalk HD

[alaskabearhawk]

Hands-down I recommend the Meco and the lightweight hoses...you can't go wrong. Here is a tip chart I made for the Meco reference the thickness of material. I do have two number one tips, one drilled out to a bit bigger and I filed little notches in the drilled out tip so I don't get them mixed up...like the notches in a fuel hose fitting.

I just have a comment about the coat hanger idea. That steel (or whatever it's comprised of) is a real crapshoot and I wouldn't recommend it even for practice. Regular RG45 or ER70S2 is cheap and will give you the feel for how it flows and bonds to the metal. All the filler rods (RG45, RG60, ER70S2, ER70S6) have a different flow characteristic and you want to try them all and practice with what you will actually be using. I have found that getting a bicycle at a thrift store and cutting it apart makes for good practice. The steel walls are thin and you can pick up a bike for 5 bucks or so. Sometimes it will even be 4130 tubing for the older 10 speeds. Welding 4130 is different from mild steel in the sense that you must be very aware of temperatures, oxidizing flames, gradual cooling, etc so as not to compromise the strength of the steel. The book by L.S. Elsea http://www.amazon.com/Aircraft-Weldi.../dp/1559182911 is one of the best out there for welding 4130 tubing. Kent White (aka the Tim Man) is an incredible resource as well: http://www.tinmantech.com/html/welding_videos.php

I have a few youtube videos about my experiences when learning welding that may be helpful. Here's the link to the conclusion:

http://www.youtube.com/watch?v=ZEA-g8sMynY

Hope this helps a bit...

Paul

[Enewton57]

I agree with what others have said in regards to Meco torch -I used it exclusively for my Bearhawk and highly recommend it. I use about 4 lbs on the Acetylene and 8 on the Oxy

[eh009us]

I have a smith AW1A (new version of the old Smith "Airline") torch, as well as #'s 1,2 and 3 tips and lightweight hoses. As for settings, watch Kent white's video on aircraft fuselage welding and construction. He recommends running the torch wide-open and setting the flame with the gauge valves.

[Yard Sale]

Wow, awesome input from everybody!

Probably be ordering the 4130 Starter Kit from Tinmantech soon.
Now to figure out which regulators to get...

[marcusofcotton]

Now to figure out which regulators to get...

I needed new regulators, was going to get two stage American made Smiths. Got talked into single stage being more than adequate - they work, but I regret not going for the two stage, though I've never used two stage to be able to actually compare.
Mark J
#673

[Tom W]

I needed new regulators, was going to get two stage American made Smiths. Got talked into single stage being more than adequate - they work, but I regret not going for the two stage, though I've never used two stage to be able to actually compare.
Mark J
#673

I've used both. With my rosebud tip (sounds like a jet engine roar), I'm consuming the oxy/act at a fast paste as I preheated aluminum cylinder heads. Dual stage is ideal as I'm there for a long time.

With the meco torch, my single stage is fine. Even when I grabbed a #7 tip to weld some 1/4" steel for a welding table, you can adjust as you do as it isn't consuming that much. Once thing to remember is you will not be welding for hours non stop. You need to move, position work, stretch... and it becomes second nature to keep the flame set.

I had a heck of the time getting thngs set up with the meco at first, finally learned to use Kent's method of adjusting pressure:
Select tip for material being welded.
Three turns on the meco - both knobs.
Adjust the pressure regulators all the way out.
Open bottles (needle full raise tank pressure on acetylene, plus quarter turn -- maybe 3/4 turn on my bottle). Oxygen -- slowly open the screw as the gauge comes up, then screw all the way open (packing is on the top, that screw should be all the way up. About four full turns on my bottle).
Now hold the unlit torch towards your cheek. Screw in a acetlyene regulator till you feel a nice breeze. Light the torch. You should have zero black soot whispy's flying off. Just a good flame. Now bring up the oxygen. Nice solid balanced flame. Oh the flame is 1/8" away from the tip? Just flick the torch up and down (pointing with the flame in the same direction) and the flame will be on the torch.

When I was all done, I looked over and realize with the 0.035" steel, uh.... my regulators had not moved off the peg rest. I wasted months trying to adjust the flame by setting pressures, that didn't register. I was cooking....

Best part was once I learned how to adjust the regulators.... get some decent magnifying glasses... it was time to go to town on some 5052. Prior to taking Kent's class, I would just leave big blobs of aluminum on the floor.... just a little correction to my method by the master... and not bad improvement in a day.

Tom

[bestbearhawk1231]

I have the Smith AW1A, does everything I need it to and it is really nice to have the option of using it as a cutting torch when you are not welding or heating with it. If you can only have 1 oxy set up I would go with a standard duty smith or victor simply because you can get the cutting head and have a more versatile set up, it is amazing how much you use the cutting head once you have one. The standard duty will also put out more heat than a meco so you are not as limited once the project is done, however, you need to really learn heat control or you will blow right through the really thin stuff. One thing I like about the AWA1A is that the valves are towards the top of the handle which allows me to hold it like a thick pencil and not bump the knobs, holding it that way is more comfortable to me and allows me to react faster when I need to pull the heat away. It also gives me better control of the puddle. I have nothing against the mecco and I feel that it would be a nice addition to my current set up. I am sure there are clusters that will be a royal pain with the Smith, but, in my book, if you can only have one type of any tool the most versatile one wins hand down. I bought the Smith HVAC portatorch setup several years before i started my project knowing that I would want the portability of the small bottles for "other" projects and would be getting the big bottles later. The portatorch set up came with medium duty regulators which have worked flawlessly. The AW1A handle has a lifetime warranty, are made in Watertown SD, and I can get the consumables from my local welding supplier. I have also heard that Tinman's glasses are the kat's meow and would like to try a set when I finally cough up the cash for them.

I usually set the pressures around 4-5 or so and adjust the flames from there. I have also used Tinman's method of adjusting regulators and it works well also. It should not sound like a blowtorch when lit. The sound should be soft and "comforting"...it should put you in almost a zen like state of concentration and relaxation while welding. I normally use rg45 (non aircraft), 70s2 or 70s6 tig rod.

[Jflyer]

To practice welding on 4130, I bought just that,...4130. Aircraft Spruce sells a box of scrap 4130 in various sizes and wall thickness for the purpose of learning to weld 4130. The box cost $28 plus shipping. It arrived yesterday and I'm happy with the amount and pieces included. Plenty of practice time. I'll plan to TIG weld my frame www.weldingtipsandtricks.com is a great site to learn all things welding. He has videos for 4130 as well

[jaredyates]

It is a good idea to practice on 4130, but there is no need to start with it. Start with mild steel and after you become comfortable, them move to 4130. As you shop for regulators, keep in mind that what we are doing with them is more like dentist work and less like farm work. Regulators that are intended for heavy-duty welding or cutting are going to have a hard time being consistent at the very low pressures that you intend to use them. A big cutting torch might run at 40 PSI on the oxygen, but for thin wall welding, you're barely going to have it off the peg. It's probably worth considering the Victor regulators that Kent sells also. He has selected them specifically for the demands that you will be placing on them.