Let’s give this a try!
Tonight I prepped 4 3ohm 10 watt aluminum resistors with in two parallel pairs with solid copper wire. I gave it 12 volts of juice and it got plenty hot quickly, so hopefully this back of the matchbook effort will pay off.
I have been reading a few other blogs about other peoples diy hbp builds and I was getting really confused. Hydraraptor is using 9(!) 48ohm resistors on his reprap hbp. That seemed really high, considering the people doing it with nichrome wire only have about 6 ohms total.
Then I realized that Hydraraptor is using 240VAC. That seems dangerous, and in one of his posts he mentions how one of his resistors failed and ended up melting a bunch of his circuit breakers. Yikes, that’s not for me.
My plan is to set this up on an aluminum plate with the stock thermistor from the makerbot kit. I’m still unable to print because of some extruder issues, but this is a good distraction while I try to figure that out. I’m also going to try building one with nichrome wire. IF it works as well then it’ll be lower profile than this resistor configuration.