Well yes, I did know that much about welding, apart from it being a very hard material. They aren’t limited to steel though. I think the examples are aluminium.
I have never done any welding and there seems to be some skill to it so I am not sure whether I should learn to weld manually first before trying to get a machine to do. I am pretty crap at manual skills and can’t make anything decent with a 3D pen, so perhaps going straight to a robot is the way to go. That way I don’t need to get gloves and masks, etc. I can just do it in a closed metal box with a camera.
Aluminum requires a different for of this call TIG (Tungsten Inert Gas) which is a much, much twitchier process, and there the fun is of course the inert gas is used to prevent the aluminum from erupting into flames itself, as well as cold-welds from oxidation in the weld area. Way harder to do right.
Regular MIG welding is a handy skill to have, and you can get into it pretty easily and it’s not hard (basically clamp tube steel in the shape you want) and gently (there is an art to getting the swirl right) mix the metal together with the wire. It took me a few weeks to get good (not welding building steel of course, just tube steel and pipe for projects). Very handy skill to have. Your local maker space probably has MIG (Artisan Asylum near me certainly does)
You can also use TIG welding for copper, we use it to connect commutators after winding them. I have never done any TIG welding on aluminum but I believe you need to use a filler for aluminum and you do not for copper.
Have many many hours on a MIG machine here at work, like you said it is mainly learning a technique once you learn the wire speed to power ratios for different thickness of materials.
They describe it as MIG and say they can do aluminium, steel and stainless steel. I don’t know if they change the gas for aluminium.
I suspect regular welding is more difficult because you are joining two workpieces with the weld. Here they are just puddling the weld on top of itself, or the base material, which it sticks to but does not weld to. They use a steel bed for aluminium.
I don’t think my local hackspace has a welder but I go there once a month for a 3D printer group meeting so I can have a look next time.
Interesting, never knew that you could TIG weld copper (never needed more than solder level connections). Do you weld them for mechanical strength, since solder is normally sufficient for most electrical connections? (or are you talking massive currents where even the resistance of solder vs. copper comes into play?)
Reading up on TIG v MIG they both use an inert gas, although a different mix. The main difference seems to be MIG uses a continuous wire feed as the electrode but TIG uses a tungsten electrode and a filler rod. I also read you can MIG weld aluminium. So I think this is definitely MIG as it needs a continuous wire feed from a spool.
Doing this kind of thing fast could be a problem, because you’ve got to get rid of the heat so that the previous metal can cool before the new metal goes on top. And if you were trying to make non-solid objects it would be easy to blow through the walls (that was my problem trying to learn to weld steel pipe – well, that and too much coffee). But it looks like they’re backing way off on time and speed to eliminate those problems. Which is likely smart.
(Yeah, TIG meanwhile is really just a very different kind of torch.)
There is a flux core wire for MIG that doesn’t require shielding gas but it spatters and fumes as bad as arc stick welding. I believe the shielding gas is argon/Co2, and makes welding almost as clean as soldering with a much better weld.
I found MIG easy to pick up and is a great addition to the shop and skill set, making you omnipotent with steel.
High temp/speed applications. With smaller armatures we solder but when you get into larger motors you get hot enough to melt solder and the faster ones will actually rip out of the comm with solder.
Ooh, now I want to pick up a gas outfit. I learned with the flux core wire and you’re right, it’s messy and nonuniform. (Not as bad as regular stick, but then the wire is about 1/40 the thickness of a stick…)
When I finally splurged for the bottle, regulator and $50 fill, I was so pleased with the result, the pain of expenditure vanished instantly. I had never done gas shielded welding before, and the silky smooth deposition with almost complete lack of spatter and zero slag made me an instant convert! Worth every penny.
Just be sure to close the valve tight! (the next time I went to use it the bottle was empty. #@*% $50!).
It is a good practice to bleed the pressure and zero your regulators on any gas bottles so there is not standing spring tension for extended periods on the diaphragm. Keeps 'em accurate.
