1 Topic by driggers

  • driggers
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  • Registered: 2012-10-07
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Topic: replace hot end resistor 5.6 Ohms

I replaced the hot end resistor with a 5.6 Ohm resistor, after the replacement from solidoodle burnt out.  I can't seem to find a definitive source on the resistor they used, so I bought a smattering of them from 2.x, 3.x, to 5.6.  I installed the higher resistance one for safety, and it heats up ok, but seems to overshoot by 10 degrees, before coming back to 190, which I had wanted to print at.

Question:  What (range of) resistance and wattage should my resistor be rated for?

fyi, I used silicone heat transfer compound and kapton tape, instead of cement, to install the new resistor.

SD2 Sanguinololu 1.3a atmega1284p, wood platform, lawsy's carriages, braided fishing line, pallet wood overhead spool mount, carboard/magnet enclosure, glass bed, E3D v6, bed levelling knobs, extended z-stop, 25A DC-DC SSR for bed heater, everything fixed to the SD2 frame, marlin firmware with some adjustments and extra failsafes enabled.  I'll never give up on you, little printer that could(n't)!

2 Reply by elmoret

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  • Registered: 2012-10-11
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Re: replace hot end resistor 5.6 Ohms

The resistor's fine, you need to autotune the PID. Search here or look in the wiki, it's been covered many times.

Filastruder - the robust, inexpensive filament extruder
E3Dv6 All Metal Hotend - the premier 3D printing hotend

3 Reply by driggers

  • driggers
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Re: replace hot end resistor 5.6 Ohms

Update on this:  I burned out the 5.6 Ohms 2W resistor.  Have installed another one that is the same until I get something better... not sure what that will be...

SD2 Sanguinololu 1.3a atmega1284p, wood platform, lawsy's carriages, braided fishing line, pallet wood overhead spool mount, carboard/magnet enclosure, glass bed, E3D v6, bed levelling knobs, extended z-stop, 25A DC-DC SSR for bed heater, everything fixed to the SD2 frame, marlin firmware with some adjustments and extra failsafes enabled.  I'll never give up on you, little printer that could(n't)!

4 Reply by adrian

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  • Registered: 2013-01-15
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Re: replace hot end resistor 5.6 Ohms

ceramic heater cartridge FTW smile
http://www.ebay.com/sch/i.html?_trksid= … ;_from=R40

5 Reply by tealvince

  • tealvince
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  • Registered: 2013-01-16
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Re: replace hot end resistor 5.6 Ohms

I think 5.6 ohms is probably okay, but 2W isn't likely high enough.  Is a 2W resistor even wirewound?  I've read that earlier SDs shipped with a 4.7ohm 5W resistor, and new ones may be either a 5.6 or 6.8 3Watt ones.  I replaced mine with a 6.8ohm 3W resistor that is specifically sold for use with reprap, so others must be using these too:

http://www.ebay.com/itm/181059052240