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I had no idea making a DIY welder would be so easy to do. And, it's pretty much FREE!
Additionally, the stick welder you get is definitely better than anycheap commercial welder you can buy.
Why is this homemade thing better than something you can buy? Because when you factor in shipping and labor and the little bit of retail markup - the companies that make typical cheap buzz boxes will skimp on copper as much as possible. Whereas you can use enough copper in this to make something really juicy, and still spend less, to nothing, compared to a store-bought arc welder.
So here's what you need to build a welder:
- Two beat up old microwaves
- Some 10 gauge wire
- Wire nuts
People throw out microwaves all the time, if you keep your eyes on the curbs.
Or, you can get microwaves at the local thrift store for $10 each.
Try the warehouse that processes donations - they have to pay to get rid of tons of broken ones.
Stuff you need for welding:
- Welding helmet ($16 and up)
- Welding rods ($6)
- Vice grip or purpose-built electrode holder ($6 for either)
- C clamp for grounding clamp
- Gloves
- Thick nonflammable (leather) clothing that will cover your arms
Disclaimer: High Voltage ELECTRICITY and lots of CURRENT! Heat, electrocution, and DANGER! You could die and you could go blind.
That said, try this at home!
See this for a lot of welding safety tips
Here are the really good how-tos that this project is informed by:
build a 70 amp welder
the tiny tim welder by tim williams
home made welding machine (via afrigadget)
Dan Hartman's how-to is good for reference, too.
And here's the quickest way to make a DC welder with a bunch of 12 volt batteries.
Additionally, the stick welder you get is definitely better than anycheap commercial welder you can buy.
Why is this homemade thing better than something you can buy? Because when you factor in shipping and labor and the little bit of retail markup - the companies that make typical cheap buzz boxes will skimp on copper as much as possible. Whereas you can use enough copper in this to make something really juicy, and still spend less, to nothing, compared to a store-bought arc welder.
So here's what you need to build a welder:
- Two beat up old microwaves
- Some 10 gauge wire
- Wire nuts
People throw out microwaves all the time, if you keep your eyes on the curbs.
Or, you can get microwaves at the local thrift store for $10 each.
Try the warehouse that processes donations - they have to pay to get rid of tons of broken ones.
Stuff you need for welding:
- Welding helmet ($16 and up)
- Welding rods ($6)
- Vice grip or purpose-built electrode holder ($6 for either)
- C clamp for grounding clamp
- Gloves
- Thick nonflammable (leather) clothing that will cover your arms
Disclaimer: High Voltage ELECTRICITY and lots of CURRENT! Heat, electrocution, and DANGER! You could die and you could go blind.
That said, try this at home!
See this for a lot of welding safety tips
Here are the really good how-tos that this project is informed by:
build a 70 amp welder
the tiny tim welder by tim williams
home made welding machine (via afrigadget)
Dan Hartman's how-to is good for reference, too.
And here's the quickest way to make a DC welder with a bunch of 12 volt batteries.
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Signing UpStep 1Dissect the Microwaves
Invite your non-hardware oriented pals over to help help dissect your donor appliances.
They'll love it. David Grosof donated one of these microwaves under the condition that we take it apart together.
Good safety tip:
You'll find a gigantic capacitor inside the microwave. It looks like a metal can with two tabs on top.
Short it out to make sure it doesn't have any leftover charge on it, before you poke your hands anywhere near. Just put a screwdriver or something metal you aren't connected to, across the two metal terminals shown here.
They'll love it. David Grosof donated one of these microwaves under the condition that we take it apart together.
Good safety tip:
You'll find a gigantic capacitor inside the microwave. It looks like a metal can with two tabs on top.
Short it out to make sure it doesn't have any leftover charge on it, before you poke your hands anywhere near. Just put a screwdriver or something metal you aren't connected to, across the two metal terminals shown here.
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from Kaychi.
THX
I havent got my MOT's yet but does anyone know what kind of current i can get out of 10 turns of thick wire on both transformers with an input of 230v @ 50hz? Also i heard that somone used 10awg wire and it melted can anyone recomend a good thickness and a supplier?
THANKS
Its better to make a welder, using thicker wires on the secondary, even with lesser turns.You just need to add another transformer..
I tried 2 transformers, 10AWG 10 turns each... secondaries in series, primary in parallel.
then 3 transformers 8AWG 7 turns each... secondaries in series, primary in parallel. (this works better)
I'm also thinking of making a 4 transformer welder, as soon as I find one more...
Anyway, as added cooling, i used the fan found in the microwave, to cool of the unit from heat. a little aluminum heat sink would also help..
Frequency change affects transformers like this: raising the frequency (more than the nameplate value) causes the transformer to "fight itself" more--i.e. more heat, due to less effeciency...though this is not considered unsafe as long as it can be dissipated. Lowering the frequency, on the other hand, causes the transformer to "not restrict itself enough" (to understand that one, take an AC power class...) thus causing TOO MUCH CURRENT to flow through the windings themselves... which can cause meltdown. Its not simply a heat thing, though it becomes heat. it is an overcurrent thing.
--DH
light dimmers typically aren't rated for inductive loads not sure what the typical wattage is either but it will work as long as it doesn't pop, if you have one on hand id recommend trying it.
the speed controller mentioned in the comments should work without any problems if that fails. don't forget to use a 20% off coupon.
http://www.harborfreight.com/router-speed-control-43060.html?utm_campaign=SEO&utm_medium=Inbound_links&utm_source=linking
Thank You..........
so you need to rectify it after the transformer, look at the wikipedia page on bridge rectifiers for more information
http://www.bgmicro.com/DIO1024.aspx
that bridge should handle some welding if you can give it time to cool off (in theory anyway)
stacking them should work fine
Pagano's hardware here on Alameda has lots of dimmers, but the ones that do inductive loads are $40 or so. The packages there say whether they are intended for inductive loads or not.
The box only goes to 15 amps and you will be blowing a lot of them at first. Probably run a 20 amp fuse with no problems. I ran a 30 @ 75% and it started to work properly, then the transistor in the box blew up. Upgrading this or decipating the heat from it will need to be done to go above 15 amp fuse safely. Also, one of the transformer secondaries smoldered, so I need to replace the wire or re-insulate it to have this welder work again. This was probably due to lack of proper heat decipation.
i also have a gigantic transformer from a big cell tower thing. it was a power supply for some kind of print shop. its is about 9ft tall with all kinds of circuits and switches and what not. it might be too big for the welder i wanna build though.
Im looking to sell that whole tower thing if anyone is interested who is in the atlanta area, you can PM me for pictures or i might post on here. it had two transformers but i was broke and had to scrap it. got about 90 bucks for it.
this is the stuff I used. It's 20 bucks for a hundred feet, and the insulation is nice and flexible, and easy to wind. As for melting, it hasn't melted on mine.
Would a light dimmer, the way it adjusts the duty cycle, be effective at all? I would replace the tiny triac with a 50 amp one of course, using just the control circuits.