Frying Heater elements

Hi all!

I just modified an old budaschnozzle toolhead into a flexy struder, and I’ve managed to burn out two heater elements trying to start it up. It heats up to ~120C and then suddenly it just starts to cool. When I check voltage and resistance, I get nil on both, while before I started it up, I had 5.5 Ohm over the heater… I fried one the other day but thought it was a fluke since I’d been handling it (maybe improperly) and so I just switched the heater element from an old nozzle and then tried again… Same result, so now I’m a bit confused…

I have had the new firmware installed since I’m using the new Hexagon, and I thought that wouldn’t make a difference, but I’m starting to suspect there are different heater elements in the two heads and that the new instructions might be frying my budaschnozzle heater elements…

Anyone who understands this electronics stuff that might have an input? :slight_smile:

Welcome to my world :frowning:

I did the exact same thing - converted from old Budaschnozzle to Flexystruder but fired it up without changing firmware. The resistor glowed bright as the temp shot up to 100C then went dark. I have been buying bits and pieces to recover from a dead heating resistor (resistors, crimps, insulating tubes). It is not fun.

The problem is that the firmware heating profile is different between the hexagon hot end and the budaschnozzle. You will want to replace the resistor again and change the firmware. I don’t know what “heating profile” really means. It may be enough to recalibrate the PID settings, but it seems the safest answer for now is to just change the firmware.

It is probably worth doing a diff between the two marlin configuration.h files (TAZ 5 vs. TAZ 5 Flexy) to see what the differences really are.

BTW, if you need a new resistor and crimp ends to attach it to your wires, drop me a PM with your address and I’ll send them to you.

Thanks for letting me know I’m not the only one… :stuck_out_tongue:

Ok, so it’s like I suspected… Pity no one mentions this from Lulzbot since I’m sure most people print with more than one extruder…

Oh well… Time to order heater resistors and crimping stuff then… Do you have a good source for them?

Thx!

// J

You can order the resistors from digikey with no minimum order. I think they are just over $1. The crimps you can buy in packs of 100 from McMaster-Carr. I have extras though if you want me to send you a resistor and 2 crimps. I can either shove them between some cardboard and send in an envelope via snail mail for $5 (add an extra $1 for an extra set). Or I can send via small flat-rate box for $9 (again, an extra $1 for an extra set).

http://www.digikey.com/product-detail/en/0/RWMB-4.7CT-ND
http://www.mcmaster.com/#9681k21/=wfndcs

Thanks, that’s very helpful!

I live in Sweden though, so I have a suspicion that shipping is going to be more than the actual worth of the components, so I’ll just save you the hassle and order them from Farnell. I also need at least two and probably get a spare for building a “filament-welder” from the leftovers of an old Budaschnozzle… :slight_smile:

But thanks heaps for your generous offer!

// J

LOL. I’d say that is a bit too far :slight_smile:

Hopefully the part numbers help you track down the pieces closer to home…