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Where to find a 120V to 12V transformer? Answered

I want to make a "styro-slicer" which needs a 120V to 12V transformer. I would like to scavenge it instead of buying it.


How many Amps do you want it to be? I don't remember Grant mentioning how many amps were needed in the video...

A lot depends on you hot wire. If you use a 3/32 welding rod expect 40v @ 24 A...

Welding rod? I though he was talking about a styrofoam cutter...

The weld rod works far better then nichrome wire and can keep a shape see last pic...

BTW click all pics to see full image....


I see...

So the welding rod is way thicker, But is better for that. If it's thicker, Doesn't need many more Amps to warm up?

Also, Which type of Welding rod should be used? I think that if I make it, I'll use Nichrome Wire, Because I already have some, And because they aren't very cheap on eBay.

If I make I'll make it so the wire will be stretched tightly, And square to the base (Somehow similar to a Bandsaw)

Here is my band saw, notice how the current does not flow through the spring... The thing about nichrome is if you apply the wrong voltage / current source it will instantly split like a fuse...


BTW Nichrome will stretch as it gets hot...

I'm lucky there is a local welding shop in Reno...

Heliarc filler rods should not be expensive...


2 years ago

I picked up a few really old beefy industrial linear power supplies. The first one I got was rated for 5V 10A, and was broken. I stripped out the old regulating circuitry and connected the output terminals directly to the main filter capacitor for 17V unloaded voltage. You can find such power supplies in antique shops. I also got 5 more of these grey industrial lambda power supplies (different sizes/types) from craigslist for pretty cheap.

This was what was inside of the 5V 10A model.


I've salvage power supplies that are pretty similar to that from UPS's

12V halogen lamp drive transformer.


2 years ago

I used a 12volt 16amp secondary and for the duration of the cut, I pushed it to 24amps, see 5th pic, hardly got the xfmr warm..


I don't know where you could find a transformer like this... Your best bet would be to parallel several smaller 12v xfmrs

Be sure to click the pic to see the whole image.

Styro Xfmr.jpgStyro Ckt.jpgStyro setup.jpgStyro Variac.jpgStyro Hot.jpgStyro Cut.jpgStyro 120-12V.jpg

1. You don't say where in the world you live, scavenge can differ place to place. To be honest it wont cost that much to buy, otherwise your down to looking through used equipment to see what you find. Typical highish current 12 volt sources are typically car battery chargers.

2. Tried google?

3 tried to identify any surplus electronic equipment suppliers near you?

4 you don't say what current you need.

For a long time I simply used a car battery and charged it as required,.