Loading

Herringbone Geared Extruder

by rhys-jones, published

Herringbone Geared Extruder by rhys-jones Dec 11, 2010

Description

This is an attempt to combine various aspects of Adrian's and Wade's extruder drivers. Specifically, It keeps Adrian's extruder clamping system, uses a prime number of teeth for good wear characteristics but uses Wade's hobbed bolt to do the driving.

As the name suggests, the design uses Herringbone gears. This ensures that backlash is substantially reduced, which should result in the extruder requiring slightly less reverse, but more importantly run quieter. The design of the drive gear is somewhat experimental. As with other gears, this uses a grub screw to secure the gear to the motor shaft. However, on this design the hole goes through the root of one of the teeth. This takes up less space, and also lets you adjust the position of the gear without taking the motor off. However, it is quite intricate. Many people have managed it, but your printer needs to be running well to do it.

Recent Comments

view all

Hi! Sorry my bad english!
How to adapt LM8UU x carriage? Any project?

So flip it yourself dude...

Come on!
The large driven gear part without holes is upside down!
How can one do a circle inside a hole 5mm in the air???
The non-holed part if printed upside-down and with 0.3 infill is half the print time btw...

Liked By

view all

License

GNU - LGPL
Herringbone Geared Extruder by rhys-jones is licensed under the GNU - LGPL license.

Give a Shout Out

If you print this Thing and display it in public proudly give attribution by printing and displaying this tag. Print Thing Tag

Instructions

Manufacture of the bolt is the same as Wades, but you'll need an M8x70 instead. I find it best to assemble the whole extruder, before marking where the hobbing needs to go on the bolt. A stack up of tolerances during build and assembly will probably mean that if we measure it off the CAD model it'll be wrong, or atleast not optimal..

Also, on my pictures the layout is not optimal. Ideally I think it should be Gear, 3X Washers, Spacer, 2X Washer, Bearing, Gap, Bearing, Washer, 2X m8 Nuts. It might be an idea to increase the size of the spacer, and do away with some washers, but I personally like that it allows some adjustment in either direction.

The final two nuts do not need to be done up tightly, doing so would mean the bearings become a little rough. The herringbone gears should keep everything aligned by themselves and the bolt takes all the torque, so the nuts only need to be lightly tightened.

When assembling this extruder, it is somewhat critical the gears are perfectly aligned. Herringbone gears try to self-center, if the alignment is incorrect they'll probably get damaged. I find the best way is to assemble everything, not tightening the grub screw on the drive gear, give the whole thing a couple of turns during which the gears should align, and then tighten the grub.

On my photos you'll notice I've used m4 nuts to tighten the idler. Ideally, you should use wing nuts instead as these allow you to adjust it by hand.

13/12/10 - Updated Idler to beef up the filament guide

18/12/10 - No design changes, but the STLs have been simplified to ease slicing.

06/01/11 - Updated drive gear holder to reduce the holes for the bearings to give better constraint. You may now need to press fit them in, or give them so encouragement with a hammer. Fortunately the bearing supports are open and therefore can flex a little to hold the bearings tightly. Also I've uploaded a new idler bracket without the filament guide, I don't think its actually needed with a hobbed bolt. It seems to be printing as well without it anyway.

02/02/11 Updated the driven gear so that the herringbone gears now contact in the recommended "stable" manner. If you already have this extruder and want this, you only need to print the driven gear, and then just flip the drive gear. Also the idler bracket has been updated for better placement of the holes. I've uploaded updated IGS & STEP files for those who use them.

15/02/11 I've pulled some of araspitfires updates into the main release as they are much better:D. Also thanks to bobbens, all the STLs should now be orientated correctly for skeinforge users.

Comments

You must be logged in to post a comment.

wrobbi on Nov 1, 2013 said:

Hi! Sorry my bad english!
How to adapt LM8UU x carriage? Any project?

KreAture on Mar 26, 2013 said:

Come on!
The large driven gear part without holes is upside down!
How can one do a circle inside a hole 5mm in the air???
The non-holed part if printed upside-down and with 0.3 infill is half the print time btw...

acashmancobb on Oct 28, 2013 said:

So flip it yourself dude...

MarcusWolschon on Nov 14, 2012 said:

Do the mounting holes and the location of the filament hole still fit the Thing-O-Matic or are the versions >july 2011 Reprap specific?

Kulitorum on Oct 7, 2012 said:

I made one, but with the springs I have (from a INTEL Cpu cooler) it's impossible to load material into the thing - it's just too tight between the bearing and the bolt. So I loosen the screws to get the filament in to the pinch, and then have to re-tighten the 4 spring screws to make it hold firmly....

JamesRPatrick on Dec 11, 2011 said:

That is quite beautiful.

Myndale on Jul 27, 2011 said:

I finished building my copy of this thing last night, for the record I printed the gears in PLA on a Mendel with 100% infill and the small gear printed fine. The main problem I had was with the driven gear, if it's even slightly warped due to printing without a heat-bed or printing with less than 100% infill then there's a chance that the bolt won't sit perfectly straight. If that happens then the gear wobbles slightly as it rotates...not a big deal with standard gears but a big problem with herringbone ones thanks to their self-centering nature.

I also had a problem mounting this on Buback's OpenX carriage (thing #6278). The driven gear dips slightly below the base of the main block which limits the number of alternate carriages it can be mounted on.

Overall though this is a great extruder, a bit more finicky to put together than the ot
hers I've built but a very sturdy design and the best one I've made so far.

Buback on Mar 11, 2011 said:

What's the gear ratio here?

rhys-jones on Mar 13, 2011 said:

Its 43/13

Nix-7c0 on Mar 6, 2011 said:

Definitely the coolest thing we've printed so far here at PSU :D Check it out: http://reprap.org/wiki/Etherda...

bobbens on Feb 19, 2011 said:

Yay! I can't wait to finally solve the bloody repsnapper issue I'm having to be able to print the last part and finally mount the sucker :).

rhys-jones on Feb 19, 2011 said:

Did you say it caused your machine to lock up during the print? I've found this with the latest version of the FiveD firmware. I've rolled back to an older release, and it seems to have fixed the issue....

jstkatz on Jan 20, 2011 said:

I'm using the free rhino 5 beta and it seems to be lacking STEP support although rhino 4 can do STEP, maybe I'm being stupid somewhere. Would you mind uploading in IGES? I've had luck with that in the past, it would be nice if there were a universally good format

rhys-jones on Feb 2, 2011 said:

Done. Sorry I was a little slow:D

rhys-jones on Jan 24, 2011 said:

I haven't been near my PC for a few days. I'll be back with it tomorrow. I'll upload IGES asap

Anonymous on Jan 8, 2011 said:

I was wondering if your Herringbone design may start off a leadscrew or direct drive approach. A horizontal fitting drivetray may evolve and replace the belt on X altogether. Nice work by the way, I like very much the drawing you made.

syncra on Dec 28, 2010 said:

Awesome! Is it actually working as well as the original Bowden/Wade versions?

rhys-jones on Dec 28, 2010 said:

It seems to be. I've only ever used Adrian's but I'm getting equally good results. Araspitfire claims he is getting equal results to his Wade's. I think the bearings could do with being a little better constrained though. Araspitfire did a fix which helps that I uploaded (thing 5134), but when I get a sec I'll do some thing more elegant.

eagleapex on Dec 23, 2010 said:

I made one of the driven gear just for fun. I love the design.

ZNahum on Dec 15, 2010 said:

Could someone make an Imperial version of this? :'( USA is so backwards when it comes to measuremenrs
&
amp;gt;:o

QuantumConcepts on Feb 12, 2012 said:

Agreed! I'm trying to use metric in my designs because our measurement system makes absolutely no sense. How are we still basing our measurements off of the length of some dude's foot? Ridiculous!
&
amp;gt;:o

ZNahum on Dec 14, 2010 said:

Whats the BOM for this extruder? Is it the same as Wades?: http://objects.reprap.org/wiki...

rhys-jones on Dec 14, 2010 said:

There is a BOM up here:

http://reprap.org/wiki/Herring...

Stoffel15 on Dec 12, 2010 said:

It isn
´t a Herringbone, its a Tank ;)

2ROBOTGUY on Dec 12, 2010 said:

What did you model this in? Do you have solidworks files for these design?

rhys-jones on Dec 12, 2010 said:

If you do want the solid edge files and get impatient, they are on RepRap's svn

Mando5 on Dec 12, 2010 said:

interesting question... :)

DrGadget on Dec 12, 2010 said:

what's the advantage of having gears to look like that? The v shape.

rhys-jones on Dec 12, 2010 said:

I was sleeping, I only posted it 8 hours ago:D

As Sublime says, the self center and the gears are always in contact. This removes backlash and makes them quieter.

SayNoToMakerbot on Dec 12, 2010 said:

The teeth always have even contact (removes backlash) and they self center.

Top