This is an original design of an extruder that has the following features:- Symmetrical load on stepper axis;- Adjustable filament pressure without spring;- Simple & open design (easy to see what's happening inside);- No need for a geared reducer, direct drive;- Support flexible filament (anti-buckling support on both extrusion and retraction);- Best bang for your buck;See it in action:*https://www.youtube.com/watch?v=F3HcuB7CWsAFiles for modification are publicly available and with a free Onshape account here:* https://goo.gl/ESpfDwFor details about fitting the coil on the stepper motor, you can find them by looking for #bicgear , #saintflint or #flintfeeder on Google Plus.05-09-2015 Uploaded some variation on the current design, namely:- MK8 gear based version- NEMA14 based version (uses smaller 625 bearings). This last version should perform very well as a "suspended" extruder on a delta with a short bowden. Very light yet powerful enough to get along with the speed.
Technical
- 1 Coil flint from a BIC or Mini-BIC lighter;
- 4 Shims w/ inner diameter > 5 mm (I used rolls from a used bicycle chain;
- 1 screw M3 5 mm length
OR
- MK8
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- PTFE liner 40 cm;
- 2 608 bearings;
- 2 screws M3 20 mm length;
- 3 M4 nuts to secure the PTFE line (2 for the loop and 1 for the start of the bowden line to the hot-end);
- 1 Step motor NEMA 1.7A (or even lower);
I added a mk11 version (luckily onshape is similar enough with freecad for me to find my way around it; cringy service otherwise, asking for phone numbers and stuff...)
ckaos
over 9 years
Thanks a lot , will take it for a spin :)
chris-nobody
over 9 years
Thanks for your help Michael !
mmemetea
over 9 years
I meant mk8, not mk7... Sorry.
mmemetea
over 9 years
I just uploaded an MK7 version. It should work, please confirm as I don't have any.
The only trouble you could run into would be due to some contact between the non-hobbed part and the conical part. Let me know if it's ok.
You should reach 150 mm/s without problem (my printer isn't rigid enough to reach this speed in a usable way but I will try for the sake of it).
chris-nobody
over 9 years
Is your Extruder usable for MK7/8 Gears?Not the lighter Gears from Shauki)
Great Invention! Thanks for sharing!
ckaos
over 9 years
Very nice design !
Two small questions:
- what is the maximum speed you tried it on ? (looking for something that can possible manage 100-150mm/s without too much trouble)
- can you also use something other than a flint, ie an MK8 etc ?
mmemetea
over 9 years
Printing speed usually 70 mm/s - Retraction 3 mm @ 40 m/s - Works flawlessly for far.
The tricky part is really to install the flint correctly.
rsenas
over 9 years
Great!!! What speed settings? Retraction and had never seen such a brilliant idea and a motor pulls it right? And again thank you for providing. Big hug.