"I need a bit of advise on how I should weld up a 100mm square box out of 1mm? I assume welding the outside edges is best so as to get to everywhere properly, but what sort of torch angle should I use etc?
I assume I strike the arc on the piece with the earth clamp on and that I should pulse weld it?"
Hmm, sounds a bit tricky! Are you intending to fold the box and do minimum welding, or making it out of five or six flat pieces? Folding is what I'd go for.
But if it's not an important job and you just want some tricky thin metal practice, do it in bits; but you may have to do five or ten to get it right....
Yes, you'll need to tack it to start with, then continue using the Thin Metal Technique (TMT) very carefully, manual pulsing, as you say.
It will be so easy to blow holes and/or distort the structure unless you proceed very carefully. If you can find a big box section of alloy or copper that fits nicely inside it will help reduce the heat. Failing that, a wood block inside with bent plates of thin alloy or copper around the joints might do. Practice on some 1mm joints first; outside joints are fairly easy on thicker metal, but you don't see many on 1mm, unless it's stainless tig welding.
If it's all squares you are using, I think I'd tack upright angle sections first, then go over tacking again till they have a seam, and if that looks okay, and they are square, tack them together, then carefully tack over the joints until they too are seamed. This leaves the bottom and top if there is one. Tack up and then tack seam the bottom.
Don't suppose you want to close the top off completely? If you do, let it cool off properly before you tack up the last hole; better to leave a blow hole, because hot air expands very quickly in a small enclosed space....
As for angles, just turn the box over and weld on the flat if you can, as normal, holding it in place with scrap wood or magnets. Trying for even semi-continuous vertical ups or downs on 1mm is asking for failure unless you are very skilled on thin metal, and have professional kit.
Unless you really need this box for something important, it would be much easier to practice on straight lap or butt joints first. If you do need a metal box this size with far less hassle, look around the electronic parts web sites, or stores like Maplins, as they often do neat metal boxes to build circuits and home-made gizmos in. (Me, I always look for the easy way out....)
I assume I strike the arc on the piece with the earth clamp on and that I should pulse weld it?"
Hmm, sounds a bit tricky! Are you intending to fold the box and do minimum welding, or making it out of five or six flat pieces? Folding is what I'd go for.
But if it's not an important job and you just want some tricky thin metal practice, do it in bits; but you may have to do five or ten to get it right....
Yes, you'll need to tack it to start with, then continue using the Thin Metal Technique (TMT) very carefully, manual pulsing, as you say.
It will be so easy to blow holes and/or distort the structure unless you proceed very carefully. If you can find a big box section of alloy or copper that fits nicely inside it will help reduce the heat. Failing that, a wood block inside with bent plates of thin alloy or copper around the joints might do. Practice on some 1mm joints first; outside joints are fairly easy on thicker metal, but you don't see many on 1mm, unless it's stainless tig welding.
If it's all squares you are using, I think I'd tack upright angle sections first, then go over tacking again till they have a seam, and if that looks okay, and they are square, tack them together, then carefully tack over the joints until they too are seamed. This leaves the bottom and top if there is one. Tack up and then tack seam the bottom.
Don't suppose you want to close the top off completely? If you do, let it cool off properly before you tack up the last hole; better to leave a blow hole, because hot air expands very quickly in a small enclosed space....
As for angles, just turn the box over and weld on the flat if you can, as normal, holding it in place with scrap wood or magnets. Trying for even semi-continuous vertical ups or downs on 1mm is asking for failure unless you are very skilled on thin metal, and have professional kit.
Unless you really need this box for something important, it would be much easier to practice on straight lap or butt joints first. If you do need a metal box this size with far less hassle, look around the electronic parts web sites, or stores like Maplins, as they often do neat metal boxes to build circuits and home-made gizmos in. (Me, I always look for the easy way out....)