wvg_ca
semi flaccid member
just thought I'd share a spare parts contraption that I built quite a while ago, for a much different purpose then, but works great for model railroading..
It's a resistance welder, not a soldering type, an actual metal welder for small scale hobby usage..
I use it to make replacement handrails, steps, weird braces, and other spur of the moment contraptions..
Made of two 100k 35v caps in parallel, fed through a switch and a 1k 1w input resistor to make it easier on my little 1amp variable supply..
then an scr fed from a 7805 from the main rails, through an old probe head, with a push button trigger mounted on the probe..
easy to use, attach the neg to a ground plate, brass is nice, won't stick, I use steel, the little bit of stick holds parts in place better, line up the two wires, and a quick push on the button, and they're welded together..
I use small 0.017 steel blackened wire for most things, they were origionally some kind of wire ties for tagging items, or for larger sizes I use 0.023 mig welding wire.. cheap, 25 bucks gets you a 50 lb spool...
It's took me maybe an hour to assemble the unit, but you can make many small wire items like handrails very quickly, and don't need to go down to the LHS ...
The steps in the photo were replacements for an old cheapy Tyco tank car, and it'll get 'upgraded' with some old blue box trucks, and KD #5's, a shot of flat black Krylon will a bit of durability , and some decals and weathering, and another low cost piece of rolling stock..
I use about 15v for smaller sizes, up to maybe 25v for larger wire with multiple weld points, like the photo below..
My supply is only 1a, max 30v, so an old train transformer may should be enough to drive this welder..
if you really need a schematic, I'll post one..
..enjoy..
It's a resistance welder, not a soldering type, an actual metal welder for small scale hobby usage..
I use it to make replacement handrails, steps, weird braces, and other spur of the moment contraptions..
Made of two 100k 35v caps in parallel, fed through a switch and a 1k 1w input resistor to make it easier on my little 1amp variable supply..
then an scr fed from a 7805 from the main rails, through an old probe head, with a push button trigger mounted on the probe..
easy to use, attach the neg to a ground plate, brass is nice, won't stick, I use steel, the little bit of stick holds parts in place better, line up the two wires, and a quick push on the button, and they're welded together..
I use small 0.017 steel blackened wire for most things, they were origionally some kind of wire ties for tagging items, or for larger sizes I use 0.023 mig welding wire.. cheap, 25 bucks gets you a 50 lb spool...
It's took me maybe an hour to assemble the unit, but you can make many small wire items like handrails very quickly, and don't need to go down to the LHS ...
The steps in the photo were replacements for an old cheapy Tyco tank car, and it'll get 'upgraded' with some old blue box trucks, and KD #5's, a shot of flat black Krylon will a bit of durability , and some decals and weathering, and another low cost piece of rolling stock..
I use about 15v for smaller sizes, up to maybe 25v for larger wire with multiple weld points, like the photo below..
My supply is only 1a, max 30v, so an old train transformer may should be enough to drive this welder..
if you really need a schematic, I'll post one..
..enjoy..
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