
In a surge of boredom I did a search for glass bottle cutting. I found this page. That shows a hot-wire bottle cutter. I cloned the design. It's basically a laminate board with a couple of screws and nuts, a spring and some NiChrome wire.
I used an old AT PSU to heat up the wire. The 5v rail is loaded with a 20-something ohm 10W resistor that can't be seen on the photo. (A load on 5V is needed to stabilize the 12V rail)
It works reasonably well.

I might come up with a rim auto-sanding contraption in the future.
Can you draw a shematic for 5V rails with resistors?
ReplyDelete-----------[10W]---> (-)
[ 5V ]
-----------[10W]---> (+)
That is correct?
You need to add some kind of load to the 5V rail. A big resistor will work. You just hook it up between 5V and GND. (+)--[ 10Ohm 10W ]--(-)
ReplyDeleteIt will get hot, this is normal. You may want to select a resistance value to make sure it doesn't get too hot and set something on fire and/or you may want to cool it.
See here for more info: http://web2.murraystate.edu/andy.batts/ps/powersupply.htm
If you have some really old HDD or something you may be able to use that instead.