heater resistor options

Hi,

My heater resistor is dead once again. It is the second time in the last two months.
It wouldn't be much of a trouble but we have different standards in my country so I cannot find the one that will suit the heater block. Either it is too small or to weak or something else...

Luckily I still have one spare left, but I cannot order resistor from lulzbot every time it goes off. The shipping is just not worth it.

4.7Ohm/7watts

Any ideas?

thanks

Switch to a heater cartridge. Something like this:
[e3d-online.com]

I cement resistors into J-heads with exhaust putty and have never known one to fail, ever. The only reason they fail is a poor thermal connection to the heater block allowing them to run hotter than the rest of the hot end.

---

[www.hydraraptor.blogspot.com]

Quote
Andrew Smith
Switch to a heater cartridge. Something like this:
[e3d-online.com]

Thanks.
What do I need to keep in mind regarding electric current voltage etc..?

The standard reprap heater is 12V/40W. The resistance will be lower than your resistor, so you might want to adjust the PWM max in firmware so that you don't run it at full power, and you'll probably need to retune your PID settings.

Or do as nophead says and install it the resistor you have so that it gets good thermal contact, the only advantage of the cartridge heater is that its easier to get good contact than with an enamel resistor.

Quote
nophead
I cement resistors into J-heads with exhaust putty and have never known one to fail, ever. The only reason they fail is a poor thermal connection to the heater block allowing them to run hotter than the rest of the hot end.

Thanks,

I was wondering about the heater block not transferring the heat properly.. but that's a design issue I guess

Could you elaborate on cementing, and what is an exhaust putty?

Quote
Andrew Smith
The standard reprap heater is 12V/40W. The resistance will be lower than your resistor, so you might want to adjust the PWM max in firmware so that you don't run it at full power, and you'll probably need to retune your PID settings.

Or do as nophead says and install it the resistor you have so that it gets good thermal contact, the only advantage of the cartridge heater is that its easier to get good contact than with an enamel resistor.

Thank you,

My budaschnozzle comes with a heat resistor 4.7 Ohm 7W- [www.digikey.com]

How would the change apply then?

This is exhaust putty: [www.ebay.co.uk]

It quickly dries to a crumbly biscuit texture. You need to heat it above 200C to cure it and it then becomes rock hard.

Edited 1 time(s). Last edit at 10/31/2014 08:47AM by nophead.

---

[www.hydraraptor.blogspot.com]