Customised Extruder using bondtech BMG clone and other bits - feeds any material :-)!

So I was having issues feeding some filaments (flex / carbon fill) either wouldn’t feed at all with Flex and carbon filaments needed more clamping pressure. Retraction also caused filament grinding. After disassembly of the Extruder to examine it could see it really only has a set clamping pressure as the idle wheel is fixed in place.

So initially tried a part of thingiverse which worked reasonably well… but then went whole hog and made this with a BMG clone extruder, custom clamp and tried to use the UPBOX heater element components but it wouldn’t feed reliably as filament was too hot and soft going into the UPBOX heater throat. (this is why the BMG was cut across the bottom to try and use the original parts). Change the heater block completley but re-used the upbox parts in the end and now it works great. Note the UPBOX uses PTC thermistors (resistance increase with temp)… i tried common aftermarket thermistor but the are NTC type and it read 320 degrees at ambient LOL!.

Theres a few things you need to do like reverse the stepper motor direction (can be done easily by swapping two wires at connector end to head PCB), scale the flow up significantly as the BMG has a ratio of 3:1. chane fans around a bit. But it works a treat and if people are interested can put up more info. Ideally you need to use the CURA mod ive done (files are on this forum and allow CURA to generate fully compatible GCODE for the UP which can be transferred using UP Studio) as its the only way to alter flow etc significantly since there is no access to the firmware.

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ohh… yeah … wiring is a bit gash… but this was experimental… wiring could be made much more tidy :wink:

Cool mod!

btw if upbox uses the same as the other tiertime pritners then the thermistor is a PT100

Cheers bjorn… ill get some of those thermistors… Curously its about 100Ohms at room temp guess that coincides with the 100 in PT100… by the way have you tried the CURA stuff I did?

they are indeed 100ohm at 25c. (and their cousin the PT1000 are 1000ohm)

but no haven’t tried cura with up studio, i use cura and send the g-code to the duet board that replaced the up board.

Cool indeed. I also have some feeding issues sometimes on my up300 even with regular ABS. It’s just unreliable ( and it’s NOT a leveling issue ) .I was thinking about some mods even I would prefer a new oem version which has control on the clamping pressure. Same object, same material, same temperature, I don’t have any issue with another printer of another brand with hundreds of printed copies .
I’ve investigating some others “lighter” ways to mod the extruder. I’ve seen compatible heater block which should make possible use of regular cheap nozzles, changing it as soon as I have an issue.
I’ve seen also an aluminium part to replace the printed part inside the extruder. I’ll see.
Adding that to the lack of gcode support, I’m more and more disappointed about my M300.
It could be so much better with some mods like yours.

Hi fastm3,

Upstudio does have support for transfering Gcode. If you look in the Old forum under new uppers, I did I post processing script and guide to using CURA direct with the Upbox. Should turn it into the tool you want it to be :slight_smile:

If you look in the old forum ( or facebook ) , you will see it doesn’t work with up300. :disappointed: I’m not the only owner who has this issue.

Which bit doesnt work with the up300?? the Cura stuff… or being able to send Gcode from Upstudio?


Sweet! Which part did you try from Thingiverse before doing the complete MOD?

Anyways I too did a modification to my ABS extruder because of the very same reason of Feeding issues.

I basically took the Feeding Mechanism from the TPU extruder and made it work with the ABS extruder. It has fixed my feeding issues and is working very well as of now. But I only have a few prints since the mod. I can say that even with a very poorly leveled bed, the ABS Extruder does not fail to extrude. I’m pretty happy with the results so far.

I will have to look into using Cura with this printer now. I’m looking forward to getting the full potential out of this printer!