MarcoZ76 Bondtech BMG Prusa Extruder Phaetus Dragon Fixed Mount MK3S/MK2.5S

Created this mount to fix the rotation of the Phaetus Dragon in the Bondtech BMG extruder i just printed from MarcoZ76 BMG Bondtech which is a excellent extruder design but check my other models as ive made improved versions of the BMG Bondtech extruder for Phaetus Dragon and better blower with Delta-P version duct . 

I printed this Polycarbonate carbon fibre with 3 perimeters 30% infill and paint on supports around the notch cutout collar where it clamps.

Printing :

Recommended to print in a high temperature material but PETG might be ok if your doing mostly low temperature stuff , I recommend ABS , PC , PA6, or ASA for higher temperature enclosures , but to be honest it should not be getting that hot at the top of the dragon with your heat break fan running , unless your printing in an enclosure above 40 degrees Celsius, PETG will probably be ok.

Model needs paint on supports in the slicer only on one surface around the lock in recess collar as shown in the pictures , which pulls away after print quite easily , not needed on the bottom of the model as a .2 bridge fully covers the hole in the center post process use a pen knife to cut that out and give it a chamfer with a 10mm drill bit and your all good to press in your PTFE tube collet.

Make sure your print internal holes are clean with a little round file , test fit a piece of ptfe tube it should not grip in the hole but move freely, i noticed my holes getting a little rougher might be time to put the filament back in the dryer as the print quality starting to show signs of degrading.

Hopefully the images are helpful in showing you how to set it up for a print or feel free to ask questions.

The cutout at the top where the PTFE collet is gives just enough room to install a locking clip for easy install and removal the tolerances are tight so if you get a little elephant foot around the base during print a quick sand or file will give you a nice snug fit so your Phaetus Dragon wont move when your changing nozzles or add compensation for elephant foot in the slicer.

I have yet to finish building my extruder as my Phaetus dragon hotend is still being used in my other printer extruder so i have not got pictures with it and the adaptor , but using cad models of the dragon extruder I have insured that everything lines up and should be the right height , I've tested the model with 4mm PTFE tube and standard collets but sizes may vary let me know if the collet is to tight or needs further adjustment for a looser fit , I've printed over 10 prototypes refining the model each time and it seems quite good to me, with tolerances generally .2 for my printer so that's what the model has been scaled for.

Parts you need :

Two m2 screws around 6-8mm  - for securing the Phaetus Dragon to the adaptor or use the ones that came with the Dragon.
PTFE Tube 
PTFE Collet 

Reference links :

The MarcoZ76 BMG Prusa Extruder can be found here :
https://www.printables.com/model/17584-bondtech-bmg-prusa-mk3smk25s-v2-fdm-printable-rhd-

My Dragon version for Bondtech MarcoZ76 BMG Extruder body base : ( look for the dragon version )
https://www.printables.com/model/1790490-updated-marcoz76-v2-prusa-bondtech-bmg-mk3s-mk25s/files

My BMG Bontech Extruder Body Delta-P type blower : ( you will also need my BMG front mod with the two mounting holes )
https://www.printables.com/model/1801356-prusa-mk3s-mk25s-bmg-bondtech-delta-p-duct-with-le

My BMG Bondtech Extruder Front mod with the dual fan mounting holes :
https://www.printables.com/model/1784174-updated-marcoz76s-bondtech-bmg-prusa-mk3smk25s-for

UPDATES :

16.07.26 V6.0 updated the z clearance around the collar as it was too small for the other half of the shell, this is now printing for a test fit but looks ok in CAD , will update this when i confirm fitting .
V6.0 - deleted
16.07.26 V6.1 Some strange artifact in V6.0 on model export not sure why, so have corrected that no other changes. ( perfection takes so much time printing again sigh.. ) ( update : fits and works well )
16.07.26 V7.0 adjusted the collar step to make it a little tighter as it clamps down with the two halves. ( 8th Print didn't seem any tighter then the 6.1 version )
16.07.26 V7.1 Adjustment for clamping force still not quite there .
17.07.26 V7.2 Adjusted collar cut again seems it has to get over a threshold for the slicer to add another layer and this model tightens the gap to give it just a better clamping force around the collar which is what i was trying to achieve with good holding force no movement , this will be the one i use everything else seems ok less i discover something else i think needs changing or someone requests a modification. ( 10th prototype printed and fits really nice so i am going to use this one on my build )

10.08.26 V8.0 "Prototype" trying a slight modification to the model to make it easier to put in the ptfe tube into the BMG Housing, unlike the earlier versions you need to print this with the larger section of the model at the top ( see V8.0 images ) so you can see how i add support for printing. previously i would insert the adapter then push the ptfe tube up from under the adaptor till its fully seated , push in the locking clip and then attach the dragon heatsink which is all a little awkward , the idea of the cutout back half is so that it can slot in fully assembled and move up into position still locking the rotation aspect with the sides while it is a little less surface area for the torque applied when changing a nozzle it should still be enough, further testing on that, but i believe this may be on balance a better solution. 

21.08.26 testing V8.0 prototype complete works much better , did notice that while i thought the Dragon used m2.5 screws which works , it actually uses smaller M2 bolts well at least the Triangle labs version i just got does, so while this still seems to grip ok in the model i will shrink the holes for tighter M2 thread and upload a V8.2 with just smaller thread holes for the M2 bolts .
(have also added some more photos )

Notes :
I have also recently published a new version of the back part of MarcoZ76 BMG extruder body specifically for an additional support that just slots into the Phaetus dragon heatsink body that STL is in the modified back half can be found here : ( look for the STL file that has Dragon on it )
https://www.printables.com/model/1790490-updated-marcoz76-v2-prusa-bondtech-bmg-mk3s-mk25s/files 

This is just my hobby and I am always working on improving my models and designs, if you have feedback on your experience good or bad, perhaps a design suggestion or modification request, leave a comment or show a make would love to see it being used as i put a lot of time into these models and share a majority of them to help others, give me a like or follow, I spend many hours making these models and I sharing for free so it would be nice to get a little appreciation in the way of a comment or make.

enjoy , hope it helps you out.