Would a power supply for a hotwire cutter running at 16v @ 5 amps (80 watts) cut any differently over a power supply running at 10 amps and 8 volts? (80 watts again). I’m going to be using 28 gauge nichrome over a distance of just over two feet if that makes any difference.
Watts are what cut. (That was gramatically questionable). Think of amps as the pressure in a garden hose and the volts is the flow. The watts would then be the amount of energy delivered.
So, yes.
Hi Deanbo,
When it came to fuffing about with power for hotwiring, I threw my arms up in the air…
I went out and bought a beaut little variable power machine from “Dick Smith Electronics”. (Not sure in NZ.)
With a dial for amps and voltage I had total control of the melt while hand-drawing the wire through any foam density.
Its not that you won’t be cluey on electrics, but I found it easy and reassuring to go with “shop-bought” equipment in this case.
Josh
Turn off the lights adjust the amps until the wire glows. Don’t get caught up in numbers. I’ve made 100’s of blanks and I have to store bought variacs.
Deanbo, Dick Smith in NZ definitely have the amp/volt adjustable power packs, but they’re pricy. I got an old Taits Electronics power pack off Trademe for about $40 that is adjustable on volts and amps and does the job well - just took a while to find it.
Karl
Will do. Thanks to everyone else for their answers. If you happen to be looking for another yourself (or your first) you may want to search for bench supply. Just trying to decide which one will suit me best.
Happy to be of help.
Another thing which worked for me was “Fishing Leader Wire.” Multiple strands of stainless wire twisted like a cable, and strong enough that its used to catch Marlin. I busted Nicrome every try and the Leader Wire powered on indefinately.
Josh
Thanks.
I got this for free from an engineer at work. Our company was cleaning house and they were going to throw about six of these in the trash. Good to have friends.
Ajusts from zero to 140 volts with the turn of a dial. Nichrome wire, 24 gauge. Works great between 12 and 20 on the dial…
a 12 volt batery charger for you car will work too…
i got a battery charger that plugs into a house outlet and wired in a dimmer switch, then used a few peices of wood and a tension bar to keep some 24g wire tight.
i played with the dimmer until it cut fast enough without breaking the wire and put a little line where that is. works wonderfully and cost me 20 USD.
One thing to consider re. the amps, is the fuse - if for some reason you draw more than the rating, say 5amps, it’s blow… the higher amp/fuse may give you more room for draw off on your “e.” Just from my experience.
Did get my 10amp variac working this weekend - four nice cuts… like buttah! Interestingly, thick NicCrome (John?) @ 14" - 10 volts was smoking hot…!
Taylor
yeah josh great minds
i use the same power supply from dick the head smith
but have noproblem with nichrome at .6mm thick with a guitar tuner head as a tensioner
very simple and effective
Quote:
Will do. Thanks to everyone else for their answers. If you happen to be looking for another yourself (or your first) you may want to search for bench supply. Just trying to decide which one will suit me best.
deanbo – I’d be interested to see the specs on which bench supply you finally settle on, and how much it cost you.
Thanks!
Yeah Paul,
I dodn’t know what it is with my experience of Nicrome since heaps of crew swear black and blue its the best…
But whatever… you get a nice big spool of fishing leader wire from any fishing shop. Easy.
yeah when someone said leader wire i was looking for single strand but it was all multi strand
wasnt sure if it was the go or not
btw. re. PM.
basically im going to go for whatever you guys reckon.
Hello there Etmo,
you should see a picture of the power supply that I am going to buy. $159 NZD. Specs below. I don’t know about anyone else but polyurethane is just getting too expensive for me.
Bench Supply. Adjustable.
10 amp, 5 - 15 Volt DC
Bench Supply. 10 Amp Adjustable
-
DC Output. 5 - 15 Volt
-
With Analoge Amp & Volt Meter
-
270mm x 200 mm x 120mm
-
230 Volt Input
Is that 14 gauge nichrome that you are using? I got myself a 13.8v 10 amp power supply with 28 gauge nichrome but it seems a little slow. Does anyone know if a thicker resistance wire (more resistance?) generates more heat?
I use to cut blanks for a sailboard company when i was in Maui and we used a automotive battery charger works good.
kc
Added in edit….
Just now, while cleaning last night’s dishes, the thought occurred to me that you might then say
‘Well, then lets go the other way and reduce the resistance!’
Which would in fact increase the power for the same voltage.
But be very very very careful, or you’ll wind up making a ‘fuse’, which might blow –i.e. melt, and you’ll then find yourself at the nasty end of a conducting path or, holding a live wire.
However if you feel a little electro shock therapy might be just what you need – sort of a high colonic for the mind – disregard all such safety advice, and start thinking about what you’re gonna say when you meet Jesus.
…but I wouldn’t recommend it.
kc
Built a hot wire system the other week. At the insistence of the hobby shop guy I put a 500mA slow blow fuse and a light dimmer switch on the high voltage side (240V) so I can adjust output on the hot wire side (carrying around 50VA). No electro shock therapy danger this way.