I have experimented with a battery charger and that seemed to work well, but I am about to buy a variac. I have been searching the archives and some of the people seem to be using train transformers or battery chargers along with the variacs. Isn’t a variac a variable ac transformer? So isn’t that all I will need to use?
Do yourself a favor
http://webtronics.stores.yahoo.net/ensavat.html
It makes a world of difference (though they have gone up since I’ve bought mine.
yes, a variac is all that you need as long as the voltage goes high enough. I think I usually set mine at 22 Volts for cutting blanks, but this is affected by your hotwire setup. lots of archives on this topic too.
I just built a hot wire using a very old variac. I was able to cut through 24" wide 1lb eps like butter using a heavy gauge wire (fishing line wire leader). I also used tuning gears from an Ukulele to keep the wire nice and tight. I took a 2 prong indoor ac cord and added aligator clips to the outlet side. I can make the wire as long as I want, but I only need about 24".
Before that I tried using a guitar E string and a door bell transformer, didn’t work. I tried using a dimer switch for a home lighting, should have seen how fast the E string and the B string burnt. Looked like the element in a light bulb. I didn’t try the dimmer switch with the heavy wire. That might have worked.
Variacs are great, but they are pricey, and they are heavy, so shipping costs will be high. I just happened to have one at work. This home made hot wire works better than the expensive store bought wire my brother has, but he has a really nice 48" wide bow. We use that to cut rocker profiles. I’m using this one to slice sheets to the thickness I want. I can make really clean even sheets at any thickness I want.
I think I was using the variac at about 40% output, maybe between 30 and 40%.
Thanks for the input. The one from circuit specialists is the one I am planning to buy and I am hoping that is all I will need.
Howzit SharkCountry
Got any pictures of your setup
'been lurkin the Compsand threads for a while,and am gearing up to
try a few.
Mahalo
Ala Mo
Sorry no pitcs. I’ll try to shoot a couple on Thursday when I go see my brother.
In the past I used piano wire,which works good+.The best wire I have found is a military braided 0.2mm wire for Anti-tank T.O.E. rockets/missles(the wire is it’s guidance system,rather than laser,radar,heat seeking or metal seeking devices).
I was going to by a train tranformer but I started using a wall socket adaptor for a recharger…works great !.Herb
I went with an old power supply transformer gutted out of a PLC. I placed a Fan dimmer on the primary side of the transformer.( Resistive type!!! Not electronic type dimmer!!! And make sure it’s a fan dimmer if you use it on the line side to better handle the Inductive load. If you use a dimmer on the load side, make sure it’s the highest wattage that you can find. And it doesn’t matter if it’s a lighting or fan dimmer, as the load is merely resistive. Any sort of lighting dimmer has to be “T” rated to handle the initial low resistance of a lightbulb, so they work quite well in these applications.)
The bow has a switch built into the it’s handle so I can kill power from there if need be. (Switch is out in that picture, as I had just made the bow and had’t bought the switch yet.) To connect the Cutting wire (stainless steel wire used for making fishing lure bodies) to the handle, I took 1/4x20 by 3" bolts and drilled holes crossways through the threads. Then I run my wire through the holes and tighten a nut on either side of the hole together to sandwich the wire in place. The free ends of the wire then run to a terminal strip on the handle right next to the bolts. (Terminal strip is a neutral bar from inside a Square-D service panel. Most of them have way to many neutral bars, and so every time I install one I take off the outer bar on either side of the panel for more working room anyways.)
Cutting frame is spring tensioned on the top side by an old spring I found in the junkyard and a brake cable from an old mountain bike.
No need for a Variac on this one, although it would likely be a little more precise.
There are many different ways to skin a cat. This is merely what works for me
Just remember kids, be careful - electricity can kill you.
Those are nice variacs, and the price is right.
And cheap if you build your own variac 