Differences between types of extruders Hi everyone! I'm building a new printer, and now I'm choosing the extruder to mount. I know that there are three types of extruders: - Geared extruder - Bowden extruder - Direct drive Anyone knows pros and cons of these? What I think is: - Geared extruder: very precise and fast with the gear system, but a bit bulky - Bowden extruder: reduces the moving mass, but have some precision problems caused by hysteresis (can cause a big decrease of precision compared to geared extruder?) - Direct drive: removes the bulky gear system, but still have a big moving mass, probably needs slower speed and works better with 1.75mm filament (not considering geared motors) https://reprap.org/forum/read.php?70,191725,191725#msg-191725 Fri, 13 Mar 2026 04:33:24 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?70,191725,215411#msg-215411 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,215411#msg-215411
The problem with the motor that you linked is that they're rather cheaply built, with sintered bronze gears, and have 2 failure modes.

The first is that if you use the same acceleration settings that you would use on a Nema 17 motor, one of the small bronze gears will break when retracting or replacing filament.

The second (and IMO, worse) is that in some of the motors, the interference fit of the main (steel) drive gear is poor, and the gear can simply spin off of the drive shaft under stress.

- Ron]]> raldrich Plastic Extruder Working Group Wed, 05 Jun 2013 03:06:01 -0400 https://reprap.org/forum/read.php?70,191725,205859#msg-205859 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,205859#msg-205859 Pacca Plastic Extruder Working Group Mon, 06 May 2013 05:24:02 -0400 https://reprap.org/forum/read.php?70,191725,205684#msg-205684 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,205684#msg-205684
Also do note the issues my picture shows is extreme. My Prusa was a year old at the time and the speed of 45mm/s was chosen above the speeds I know did not leave the ghosts on purpose to show the effect of going fast with a heavy carriage and bed. if you keep a Mendel based machine below 30mm/s even with a threaded rod based machine you do not really have these issues. I would also imagine that machines like Nopheads Mendel 90 are far less prone to it due to the added strength of the frame and better belts.]]> Sublime Plastic Extruder Working Group Sun, 05 May 2013 13:57:29 -0400 https://reprap.org/forum/read.php?70,191725,205595#msg-205595 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,205595#msg-205595 Tantillus reduces the things that I don't like using fishing line and gears to connect motors with axes.]]> Pacca Plastic Extruder Working Group Sun, 05 May 2013 08:01:29 -0400 https://reprap.org/forum/read.php?70,191725,205585#msg-205585 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,205585#msg-205585 nophead Plastic Extruder Working Group Sun, 05 May 2013 07:36:12 -0400 https://reprap.org/forum/read.php?70,191725,205565#msg-205565 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,205565#msg-205565 I prefer to have a better control on extrusion and retraction, and that's why I'm trying to understand if also a lightweight motor can reduce very much the maximum speed and acceleration!]]> Pacca Plastic Extruder Working Group Sun, 05 May 2013 05:20:12 -0400 https://reprap.org/forum/read.php?70,191725,205547#msg-205547 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,205547#msg-205547 Sublime Plastic Extruder Working Group Sun, 05 May 2013 02:44:56 -0400 https://reprap.org/forum/read.php?70,191725,205545#msg-205545 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,205545#msg-205545 The weight of an extruder motor (nema 17) is approximately 0.35 kg. I will have the same problems with a light weight motor like this one that weights only 185 g?]]> Pacca Plastic Extruder Working Group Sun, 05 May 2013 02:39:33 -0400 https://reprap.org/forum/read.php?70,191725,205517#msg-205517 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,205517#msg-205517
]]> Sublime Plastic Extruder Working Group Sat, 04 May 2013 23:26:44 -0400 https://reprap.org/forum/read.php?70,191725,205449#msg-205449 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,205449#msg-205449 Pacca Plastic Extruder Working Group Sat, 04 May 2013 16:28:05 -0400 https://reprap.org/forum/read.php?70,191725,194231#msg-194231 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,194231#msg-194231 Greg Frost Plastic Extruder Working Group Sat, 23 Mar 2013 09:04:05 -0400 https://reprap.org/forum/read.php?70,191725,194061#msg-194061 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,194061#msg-194061
There are also other odd differences. For some reason the Arcol's overhangs curl up a lot more than J-Head's, even with everything else being the same (including the specific roll of plastic). Maybe something to do with ABS's elastic properties after being pushed through a small hole?]]> ttsalo Plastic Extruder Working Group Fri, 22 Mar 2013 16:37:55 -0400 https://reprap.org/forum/read.php?70,191725,193371#msg-193371 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,193371#msg-193371 jheadnozzle.blogspot.ca] of the length of the exit hole on a real j-head from hotends.com compared to a budasnozzle or makergear you will see it is longer then them which results in higher pressure. As well as a real j-head is also drilled a smaller diameter then rated resulting in higher pressure then its rivals of the same rated size. I have tried hotends with exit holes that were short like the buda and they do not work well for Bowden cable extruders.]]> Sublime Plastic Extruder Working Group Wed, 20 Mar 2013 13:52:47 -0400 https://reprap.org/forum/read.php?70,191725,193308#msg-193308 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,193308#msg-193308 -------------------------------------------------------
> The retraction issue is not a
> much of problem with some hotends as it is with
> others. What I found was we want a high back
> pressure hotend so when we retract it stops
> extruding very quickly. This means a long exit
> hole and medium length melt zone. Amazingly enough
> though these are the characteristics of a properly
> made J-head so they are readily available.

Really? I have been running a 0.4 J-Head MkV-b and it has much less back pressure than 0.35 Arcol V4 (the difference in force is very obvious when pushing filament by hand). The difference is apparent in the output too, the Arcol gives sharper, more accurate output with just half the retraction compared to the J-Head. And you say that the J-Head has high back pressure...?]]> ttsalo Plastic Extruder Working Group Wed, 20 Mar 2013 10:05:19 -0400 https://reprap.org/forum/read.php?70,191725,192930#msg-192930 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,192930#msg-192930 I don't really want to change the extruder I'm using, I was only thinking for a new printer :D]]> Pacca Plastic Extruder Working Group Mon, 18 Mar 2013 18:42:44 -0400 https://reprap.org/forum/read.php?70,191725,192926#msg-192926 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,192926#msg-192926
The problem you mention looks like a little bit of Z wobble when it occurs and can be overcome with some frame stiffeners so no real need to use a bowden extruder to stop it.]]> Sublime Plastic Extruder Working Group Mon, 18 Mar 2013 18:35:49 -0400 https://reprap.org/forum/read.php?70,191725,192925#msg-192925 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,192925#msg-192925 I thought that the problem of the mass of the extruder was linked to the power of the motor of the X axis (considering a common prusa mendel) and to the stiffness of the structure of the printer]]> Pacca Plastic Extruder Working Group Mon, 18 Mar 2013 18:29:38 -0400 https://reprap.org/forum/read.php?70,191725,192881#msg-192881 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,192881#msg-192881 Sublime Plastic Extruder Working Group Mon, 18 Mar 2013 15:43:21 -0400 https://reprap.org/forum/read.php?70,191725,192871#msg-192871 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,192871#msg-192871 And the mass of the motor reduces so much the maximum speed and acceleration?]]> Pacca Plastic Extruder Working Group Mon, 18 Mar 2013 14:53:14 -0400 https://reprap.org/forum/read.php?70,191725,192853#msg-192853 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,192853#msg-192853 d2oadd98wnjs7n.cloudfront.net]]]> Sublime Plastic Extruder Working Group Mon, 18 Mar 2013 13:37:19 -0400 https://reprap.org/forum/read.php?70,191725,192821#msg-192821 Re: Differences between types of extruders https://reprap.org/forum/read.php?70,191725,192821#msg-192821
I also have the same questions,
someone with more experience could explain better?

Within the direct drive type which is the best model designed so far?


Thanks
neo]]> neo-_-man Plastic Extruder Working Group Mon, 18 Mar 2013 11:41:51 -0400 https://reprap.org/forum/read.php?70,191725,191725#msg-191725 Differences between types of extruders https://reprap.org/forum/read.php?70,191725,191725#msg-191725
I'm building a new printer, and now I'm choosing the extruder to mount.

I know that there are three types of extruders:
- Geared extruder
- Bowden extruder
- Direct drive

Anyone knows pros and cons of these?

What I think is:
- Geared extruder: very precise and fast with the gear system, but a bit bulky
- Bowden extruder: reduces the moving mass, but have some precision problems caused by hysteresis (can cause a big decrease of precision compared to geared extruder?)
- Direct drive: removes the bulky gear system, but still have a big moving mass, probably needs slower speed and works better with 1.75mm filament (not considering geared motors)]]> Pacca Plastic Extruder Working Group Wed, 13 Mar 2013 02:51:46 -0400