Variac vs. computer power supply or battery charger? Depends on how often you will be using it. $150-$200 is pretty steep for 2 or 3 builds.
I have an almost new 6 or 12 V manual car battery charger with 2 and 6 amp settings. Our computer specialist at work gave me a 12 V - 9 amp computer power supply for free from an old computer – haven’t tried it though.
I cut lots of race SUPs with mine. I use .035" stainless steel wire. I barely use the power it has. Probably only turn up the juice 25%. Get it too hot and it burns the rocker template. The thimble trick never worked for me. I prefer to run cooler and just pull slower. Less problems.
It looks like this.
No idea what the power is. The fuse is 5A. Guess how I know that! Finally switched it out to a slow blow fuse. Ha!
I’ve decided to get a DC lab power source. Cheapest here and suposed to be safest cause it only goes up to 30v and 5 amps. All the charts, formulas say this is right power.
Just waiting for wire before I make the bow and buy it.
Testing pu glue now on EPS.
Still setting up lights and building shaping stands.
Still researching wet out table method vs vacuum infusion method.
The lab supply and the wire sound nice. If you can, please let us know what you used for volts and amps with your length of 26 ga wire. Did you make a bow yet? I found out that one needs a spring for tension as the wire elongates when heated.
Volts, amps , and ohms...I took the class twice and failed...somewhere there is a formula...and lots of people to confuse a low tech guy like me.
House voltage in the United States is about 110 - 120....I'm told it's 240 in Europe ???? that could cause some problems.
The nichrome wire that a Swaylock's brother gave me made everything work right...I think it was 22-24 gauge.....I'd love to get some wire from Surfding if he still has some. I will post photos of my very old Veriac.
I never turn the dial past 24 (volts?). I have a 24 inch bow and a 10 inch bow. The first few blanks were cut 24" wide. Then we learned we could buy foam blocks 12 inches wide....that made hot wire cutting much better...no more snapped wires. Make sure you work in a well vented area and please wear safety glasses. I had a wire snap and breese by my face....just touched my cheek a little bit....thats scarry.....Have fun...be safe.........Stingray.
JJrandy, go to the Jacobs online link above and read thru it. There are links on that site to rablesa. This is where I cut thru all the info and got an objective summary.
I have bought wire from Jacobs (quick shipping, good tables) and have already done a couple boards. 28"/.72m 26 gage nichrome wire, 14v, 4 amps for rockers across 23" and 25" wide EPS. My power supply is a manual car battery charger with a amp meter on the front panel, but I never get the full nominal output (the 12v 6a setting gives me 14v 4a) as it still thinks it is trying to charge a battery. A few more watts (volts times amps) would have been nice for the 28". I made a smaller 8" bow for rail bands that cuts so fast that one gets into trouble, even with the battery charger on its lowest setting. I suppose the main thing is to know where you need to start power-wise and have room for adjustment up and down. I have access to a variac and a lab supply at work but have yet to try them, maybe on the next block of foam…
