Guys, im having lots of trouble with the latest prusanozzle.

Nicolas_Arias · November 17, 2013, 3:10pm

First, the instructions say that you have to turn down pid power for the heater cartidge becouse its super hiper mega powerfoul. If i turn it down to half (like the instructions says) its terribly slow (like hotbed slow) to heat.

Second, if i use it without any heaterblock isolation, it wont reach 250 (as instructed for ABS). If i wrap a few layers of kapton on the heater block only, when printing with PLA, it gets blocked. If i take the kapton out, it works with PLA.

Im using the 20mm included fan to cool the heatsink.

Any hints?

@Josef_Prusa ?

Thomas_Sanladerer · November 17, 2013, 3:24pm

Are you referring to this version?
http://www.reprapdiscount.com/hotends/43-prusanozzle-original-by-josef-prusa.html

Nicolas_Arias · November 17, 2013, 3:25pm

yes

Josef_Prusa · November 17, 2013, 5:12pm

Hi. Newest revision has new heater. It is in the bundled manual. I wasnt able to update the site yet as im moving offices. Its 20W. Set PID MAX to 255

Whosa_whatsis · November 17, 2013, 5:34pm

For the 40W heaters, I added a feature to Marlin to set the maximum power separately while the temperature is outside the PID functional range. It was already set up to function in bang-bang mode whenever the temperature was outside a certain range of the setpoint, so I just added a second variable called “BANG_MAX” that replaces “PID_MAX” while it is in this mode, so that you can quickly heat up using full power and then limit the maximum power to make it easier to maintain a steady temperature.

Nicolas_Arias · November 17, 2013, 6:56pm

@Josef_Prusa , PID MAX is 255, but its the same thing.

Nicolas_Arias · November 17, 2013, 6:56pm

@Whosa_whatsis , even with bang bang, at full power, it doesnt work.

Whosa_whatsis · November 17, 2013, 8:38pm

Changing that setting should have made a big difference. Check again to make sure the changes compiled and uploaded properly. Also check the voltage that’s actually getting to the cartridge heater. If it can’t reach 250C at 12V and 100% duty cycle, either something is actively cooling the block (like a fan pointed the wrong direction) or it is defective.

Nicolas_Arias · November 17, 2013, 9:29pm

@Whosa_whatsis same controler (x3) with same psu, on a e3d can reach 250 and higher really fast.

the cartidge is not ok.

@Josef_Prusa

Sanjay_Mortimer · November 18, 2013, 1:19am

I’m fairly sure that the heaters that @Josef_Prusa and I (E3D) are using come from the same company, through the same supply chain.

Their quality control isn’t great and often a heater has a very high resistance (low power) - nominal in latest batches is between 3.8 and 4.2 ohms. But one in every 100 or so can be between 10 and 20 ohms, which is basically useless.

We QC our parts before they go out the door with a quick jig and multimeter test to ensure customers don’t get the bad ones.

Nicolas_Arias · November 18, 2013, 1:23am

i measured the cartidge, is 3.6.

anyways, e3d is back on the printer, working like a boss. Now i will figure out how to change the heater cartidge on the prusa.

Nicolas_Arias · November 19, 2013, 3:24pm

@Josef_Prusa , so?, any hints?, im sure that how this nozzle is working is not ok, it haves to be defective.

Josef_Prusa · November 19, 2013, 4:39pm

I now ship czech made cartridges. So far I had to replace way more Chinease heaters than these. Chinease ones went dead when stored for few months Nicolas please send me picture of your setup. Can you upload pic of your setup and the nozzle? Im really sorry you are having troubles as I gathered some great feedback from richrap, kai (laywood) and others.