Knurled surface finishing library

by aubenc, published

Knurled surface finishing library by aubenc Jun 6, 2011

Featured Thing!


YAPML yet another poor man's library that makes things finding it hard to render and taking its time to compile.

In this case the self-replicating polyhedron is intended to give a mechanical touch to your freshly (or not) designed cylindrical surfaces. Hmmmm... you can also thing that those things all-around the cylinder are diamonds and use it for jewelry.

The examples scad provided uses OpenSCAD MakerBot Font Module by grokbeer licensed under BY-SA-NC license (link in the instructions section)

Photos... aubenc.imgur.com/knurled_finish_surface

(Just in case you don't read the comments bellow)
Video by sirmakesalot (thank you very much!!)... youtube.com/watch?v=uz8h--NsX7E

Things using this library :-)

Bowden Clamp for Ultimaker by owen

Spindle for 5lb spool by mikeq

Knurled "topper" for stepper motors by Pazu

Ultimaker Hobbed Bolt Release by bkubicek

Hobbed bolt holder by coffeeMaker

Shane's Coral Frag Plugs by sgraber

Bowden Clamp for Ultimaker (Feeder End) by pit3k

Recent Comments

view all

Is it a W, E, M, or 3?

My Philips head screwdriver inst fitting into it, do I need to scale it up or down?

oh right silly me Thanks !!

Liked By

view all


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


Go to thingiverse.com/thing:6844, grab the Font Module, follow that thing's own instructions to be able to use it and come back.

Go to thingiverse.com/thing:8796 to get the screw library, follow that thing's own instructions to be able to use it and come back.

Download 'knurledFinishLib.scad' and drop it into your OpenSCAD library folder or the folder where you are writing your OpenSCAD script.

Use 'knurledFinishExamples.scad' to start playing with this library.

Knurl things.
Print them.
Share them.


You must be logged in to post a comment.

Zackalegomaniac on Apr 14, 2014 said:

Is it a W, E, M, or 3?

Zackalegomaniac on Apr 14, 2014 said:

My Philips head screwdriver inst fitting into it, do I need to scale it up or down?

harnelbe on Feb 21, 2014 said:

A real masterpiece ! i received the sample from makerbot ! Incredible ! Great work !

aubenc on Feb 21, 2014 said:

Glad you like it, thanks a lot !

willkibble on Feb 17, 2014 said:

is it possible to make longer ones of these as need a long nut and bolt for my new invention. thanks!

aubenc on Feb 17, 2014 said:

it is possible to make them any size you like. It is also really easy to do if you are used to OpenSCAD, it should work just changing a couple of parameters in the script.

pranjalpd on Oct 21, 2013 said:

Hey can you post the actual dimensions of the files pl......I'm comparing some prototypes

aubenc on Oct 22, 2013 said:

Well, I guess I could :)

There's a lot of "dimensions" here: Diameters, lengths, tolerances, for bolt, nut, knurls and also the dimension for the knurl's pattern...

You'll find them all into "knurledFinishExamples.scad", there's no need to know anything about OpenSCAD, it's just a text file and all the dimensions are easy to find.

Hope it helps!

gfolkert on Jul 21, 2013 said:

I printed some various sizes....


Spun together:

MrPreTechEd on Nov 7, 2013 said:


How much do they weigh? (what infill % did you use)

RichMac on Jan 7, 2013 said:

Mine didn't fit together, but I fixed it! They weren't perfectly round, and jammed. So I dropped the nut (made of PLA) in a cup of boiling water, then ran it on the bolt. Better, but still stiff. Then I heated the bolt, and used the improved nut to ease the thread. When the bolt cooled, it fitted perfectly!
A useful way to get PLA things to fit.

aubenc on Jan 7, 2013 said:

Cool! Nice tip!! However, wait... they weren't perfectly round??? I'd would check the tension of the belts and grease/oil the rods!

polymaker on Sep 27, 2012 said:

Can you knurl interior surfaces too, like the inside of a pipe?

aubenc on Sep 27, 2012 said:


Well, it should be as easy as extracting the knurl cylinder from another cylinder. The only thing is...

...right now I cannot tell what are exactly the inner/outer diameters for the knurl.

I guess that it shouldn't be difficult to find out by taking a look to the library. Hopefully I can find some time in the following 2 days if you are not in a hurry ?

siderits on Mar 12, 2012 said:

Very nicely done. Thanks for teaching me the End cap trick!

aubenc on Mar 12, 2012 said:

You're welcome! Thanks for the comment :)

jamesglanville on Jan 3, 2012 said:

Wow. Instantly my favourite show-off piece, and printed perfectly first time :)

aubenc on Jan 3, 2012 said:

Thanks! Is very rewarding to hear that printed well !!

(threads that match can be a little bit tricky)

MrItch on Aug 28, 2011 said:

Great design!

Printed first try with no modifications necessary (or cleanup required)

sirmakesalot on Aug 27, 2011 said:

Awesome! I tried this when I first got my TOM and it didn't quite work. Now I have learned a few things and have my machine dialed! worked on the first try no cleanup! Video to come later tonight, Sweeeeet!

aubenc on Aug 27, 2011 said:

I can't wait to see that video!

Next step: Use the libraries to make your custom bolts, nuts... "whatevers" and post the pictures/videos of them :-D :-D :-D

Tinkerer on Aug 22, 2011 said:

I made a set at 1.00 scale, but I could not quite get the nut to fit. I reprinted the nut at 1.05 scale and it threaded on, but maybe a bit looser than I would have liked. So probably scale of 1.02 or 1.03 is right. Did this work fine for everyone else at 1.00 scale for both?

aubenc on Aug 22, 2011 said:

Sorry to hear that :( In fact, this set is not meant to be scaled.

Because every printer is different, there is a little tunning to get this working fine. Printing the bolts at higher feedrate and the nuts at lower speed helps with the quality of the print but may make the fit to tight or impossible.

There are parameters in "knurledFinishExamples.scad" to help.
In your case I would set n_gp in nut_4_Makerbolt() module to 0.25 and see what happens...

I also encourage everyone to play a little bit with the screw library (thingiverse.com/thing:8796) to find out what are the profiles and scad (gap) parameters for bolts
amp; nuts gaps. I've successfully print threads that work from 7mm to 95mm.

Once you find the right parameters for, let's say the little threads, finding the right ones for the larger ones ins much easier and everything in the middle is quite straight forward :-D

bstott on Jun 20, 2011 said:

Yes, for the design. I have found very few things that will Skein right off and print VERY well. I've gone nut
amp; bolt crazy. The picture is 2X because I was having problems with another small print. The 2X came out beautiful. I can't put it down. So, I'm not making about a dozen for some Boy Scouts to play with. The regular size also prints amazingly well.

One suggestion/request - knock the knurls down to about .75 and fillet/radius them a little more. They are authentic but, man they hurt. :-D

aubenc on Jun 20, 2011 said:

Yeah, the parameters I used were intended to give a nice result for the size I was uploading the examples here but can be too wild when you scale it up :-D

Well that's the magic of OpenSCAD, just change the parameters to taste (to make it even more aggressive :-P )

bstott on Jun 20, 2011 said:

To clarify. The knurls to be .25 smaller or .75 of their present values. Here is a picture of the differing sizes I'd printed.

bstott on Jun 19, 2011 said:

I like printing good designs. It makes the bot look more than its normal amazing and sure brings the childish joys back. I just make a few calculated SF settings, generate gcode, print and watch magic happen. The tolerances are right on.

aubenc on Jun 19, 2011 said:


...making one of those :) and what an awesome print!!

...uploading the photo

...the comment.

I was adding a surface smoothing parameter which I thought it was ridiculous because bot1334 does already this job :-P Now that I see your print I'm also happy that I did it.

Anonymous on Jun 9, 2011 said:

This could be modified to be the handle of a double edge safety razor.

aubenc on Jun 9, 2011 said:

I'll love to see the designs using these libraries!

(so don't forget to share them!!!)

MakeALot on Jun 7, 2011 said:

Where is your Flattr button? =-O

aubenc on Jun 7, 2011 said:

What? It's not there?? ;)

caru on Jun 7, 2011 said:

Damn, I just finished printing 8 bolts and 12 nuts before I saw this :'(

aubenc on Jun 7, 2011 said:

Yeah... I was keeping this thing on-hold till you finish to print them :-P :-P :-P

Anonymous on Jun 7, 2011 said:


aubenc on Jun 7, 2011 said:


syvwlch on Jun 7, 2011 said:

Love it!