Thin sheet metal

[itsme]

Hello all,

I'm busy making a small pulsejet engine and have rolled all the cones and tubes from 0.5mm steel sheet. The problem I now have is trying to weld this stuff. I've tried an arc welder with 1.6mm rod and 55amps (as low as it would go), but ended up burning big holes in everything. I have little experience with welding, but know that there must be a solution. I've thought about silver solder, but these engines glow red when running, so I've got a feeling that that may not work. The only equipment that I have available to me is an arc welder.

Any ideas???

Thanks
Warren

[DSL PWR]

Clamp the sheet to a heavy pipe (1/2" thick) of the same diameter, and step weld. The pipe will act as a heat sink. Just make sure to weld small spots at one time, and let the piece cool between runs. I don't know if this will work, just an idea.

[HuFlungDung]

A little tig welder would be nice for a project like that. But that's expensive to get set up.
If you were considering silver solder, you must have a gas welding outfit available, too. Why not try gas welding (with steel filler)? Or, roll up the edges, to make a butt joint and then fuse them by gas welding (no filler added).

[kywoodwrkr]

itsme,
What kind of plans did you use in amking your pulse jet engine?
When I was in high school, late 50's, I made some steel mandrels for working some steel tubing ot shape for welding.
I never completed that project.
I thought the plans and etc were in Popular mechanics or some such magazine of the time.
Always wanted to revisit that idea.
Would appreciate any little guidance you might have.
Thanks.
DaveP

[itsme]

Hi Dave,

I haven't really done anymore on my pulsejet - the whole welding thing has put me off a bit and I've been busy with other things. They are very appealing engines though, especially if you want to irritate your neighbours...

The engine that I am building is actually of my own design (well almost...). There is an excellent website that is all about pulsejet engines. On this site, you will find many downloadable plans for engines, as well as a pulsejet design program that is based in Excel (this is what I used to design my engine). All these plans are free and there are also forums where you will find many people to talk to that are actively building and running these engines. I found the people there very helpful - a bit like CNCZone, I guess.

The site can be found at:
http://www.pulse-jets.com/

The above site is definitely a good starting point if you are looking at building one or just want to know more about them.

I hope this helps.

Regards
Warren

[kywoodwrkr]

Warren,
Thank you for taking the time to respond.
And to give such a good response!
That's all I need is another project! :-|
Seriously, I do appreciate the information.
Started another folder in my CNC/CAD folder.
Thanks.
DaveP

[jrc347]

itsme, i could tig weld the pieces for you. I need the practice and I wouldnt charge you anything (you would have to pay for shipping though). drop me a line if you want @ jrc347@comcast.net

Jeff

[DareBee]

itsme

A TIG torch set is really quite inexpensive. I can go to my local welding supply and buy 1 for $100.
You will need tungsten, filler and gas to get started. Plug the torch set into your DC welder and way you go.
If you do this you may want to try a piece of aluminum as your strike plate as aluminum wont contaminate your tungsten the way that steel will.

[torker]

itsme...It is possible to weld thinner material with an arc welder. I've learned this the hard way lately. I'm working for an outfit right now that has need for repair of anything and everything....except they only have a big ol' arc welder. I've found with light sheet metal that I can weld it. What I do is use 3/32" 6013 rod in the stinger and feed in 1/16" RG 60 welding rod with the other hand. Hold the 6013 with a long arc, so it mostly burns just the gas rod. If you get it just right you can weld like this. It just takes a little practice. You may also want to use the heat sink trick also. Hope this helps!
Russ

[pfred1]

itsme

A TIG torch set is really quite inexpensive. I can go to my local welding supply and buy 1 for $100.
You will need tungsten, filler and gas to get started. Plug the torch set into your DC welder and way you go.
If you do this you may want to try a piece of aluminum as your strike plate as aluminum wont contaminate your tungsten the way that steel will.

It just seems to me that a TIG setup is more than just the torch. Don't you need the power controller (pedal)? I like to use mine with my TIG welder. How do you get the gas plugged into just any old welder too? The aluminum strike plate is an interesting way around the frequency box I guess. Aren't most welders constant voltage and TIG needs constant current or something like that? Was a while ago when I paid attention to things like that but I sort of recall something along those lines. Oh in case anyone is wondering my Miller "EconoTIG" was like $1400 it's about as cheap as I think anyone can get into TIG welding. It lays a pretty bead but it's slow and is crap for inside corners (arc flame wavers).

Now MIG welders can come cheap, and they'll do thin stock OK. I think for hobbiest use MIG welders are the best single all around type. Out of flat position I'll pick the MIG over the TIG (and the MIG rocks inside corners). Well I don't have one of them laser welders yet, next one I get, but I have all the other common types MIG/TIG/Stick/Oxy-Acetylene. You get a MIG you can probably sell your buzz box welder to someone else who doesn't know any better. If you want to weld big stock just throw a fan behind your MIG and have at it! You can do like 1/4 thick with them cheap 110V MIGs (the fan is the secret).