TAZ 3 - Extruder Not Heating

Hello All,

I puchased a TAZ 3 a couple of weeks ago, started with nil experience, been learning how to use it and the required software since with some success.

In the last few days I had some drama’s with print quality. First print layer would develop ridges or peaks in the print lines. I went from ok (always improving) print quality to having these problems.

Using the stock L’bot TAZ slicer config’s showed the worst occurance of the ridges… only changes were for ABS filament purchased locally.

Playing with the slicer settings (custom) i did manage to minimise the line peaks, but not eliminate them fully. Once a peak/ridge developes the printer head/nozzle will then follow the ridge and repeat the peak in the next line, thus all subsequent layers would have issues.

After many attempts to improve these issues ( reading the forums, tightening all bolts, trying different filament, different filament settings, removing the extruder to clean, relevelling the bed, resetting all slicer settings etc. changing slicer versions) the extruder heater stopped working during a print.

Can anyone advise where to start looking for a fault with the heater?

I have checked all of the fuses, they seem fine, as do all electrical connections and wires…

Not sure if the extruder has been playing up therfore a possible cause for the printing problems?

I am in Australia, replacement parts from L’bot are at least a week in shipping, but I should be able to source most electronic parts locally.

Really keen to get it up and running again…

Photo 1. Lots of peaks

Photo 2. Improved after adjustment of slicer settings, ridges not completely eliminated, but the extruder heater died during this print

Update, found a forum topic with extruder heater problems, but a different cause. However a comment by Orias allowed me to find the problem…

I measured the resistance of the Heat Resistor and the Thermistor.

Thermistor measured a resistance of ~80 Ohms, at 32 degrees C ambient temperature, meant to be ~100k at room temperature, so not sure if being 32 degrees accounts for the difference. If it is not right I guess that means that the extruder temps could be incorrect?

The Heat Resistor came in as an open circuit, so it would seem that is my problem.

Will try to source one locally, and have to figure out why it only lasted for only a few hours of use…

Will get a couple of spares as well as spare fuses etc…

Have you identified the location of the disconnect? Test the resistance of the red wire pair both on the connector and as close the the large green component (heater resistor) inside the heater block. The white PTFE insulating tubes can be slid up to expose the component leads.

If you can’t find parts locally and you’re still within the 90 day printer warranty (you should be) we can send a replacement heater resistor. A guide on replacing the resistor can be found here: http://www.lulzbot.com/support/replacing-your-budaschnozzle-heater-resistor-or-thermistor

To start with a warranty replacement, send an email to Support@LulzBot.com with your TAZ 3D Printer serial number (found on the back of the printer near the lower corner of the electronics enclosure), your order number and shipping address and we’ll help however we can!

Thanks Orias,

I have read a lot of the forums and you seem to always have great responses and promt replies.

I have sent an email to support. (will follow up that email with the serial number) Definately a busted heat resistor, but still unsure about the thermistor and if it is reading correctly.

Will get a few spares so that I am not held up waiting for replacement parts if I have the problem again. Thats the deal with electonics, they can fail at any time. Recommend to others to have these on hand as well as the fuses…

looking forward to getting the TAZ 3 printing again…