MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.

Download Now


KNRLR - a tool for making knurled bolts which are actually spiky

by chopmeister Apr 21, 2012
Download All Files

Thing Apps Enabled

Please Login to Comment

The only issue with such tools for me is that the diameter of the cutting wheel reduces quickly when I use them, so the attack angle changes with time, defeating the purpose of the tool. May be I should look for better cutting wheels though.

Still I should have used your tool or a variant to make my own (new) kind of hobbed bolt. I wrote about it here http://betterprinter.blogspot.fr/2013/03/which-hobbed-bolt-for-filament-feeder.htmlhttp://betterprinter.blogspot....

This works great, thanks a lot!! :)

hi! this looks like an awesome tool! Could you post some pictures of the hobbed bolts? If you have some around :)

thnx! :D

Using the threaded part of a bolt will cause the problem that it will try to twist the filament as it progresses. (Beeen there.... :) )

Yes you get a great grip. Thats why my bolts now have also a tiny groove in the middle. That helps center the filament and also creates the "spikes"

What kind of groove? Is it circumferential? How does it keep the filament from twisting?

Hi, thanks for the comment. You are right. I tested the bolts and they work good, but the filament does try to twist. Could you post a pic somewhere how you solved the problem?

I think he means to not use this bold design at all, but to use the 'standard' Wade's bolt with an added middle groove. I've sketched a picture of what I think it would look like http://cl.ly/Gc6Fhttp://cl.ly/Gc6F

Okay, I'm apparently an idiot and can't visualize how this works. Do you have a video of it in use by any chance? DONT_KNOW

I didn't have one, but I made one for you: http://youtu.be/T7cabOkz2DEhttp://youtu.be/T7cabOkz2DE

Enjoy. :)

Thanks. I couldn't figure out how the gearing made the Dremel go up and down. It's for registering the cuts (nothing to do with the Dremel) and the fixture just pivots the cutting wheel into the bolt. I see now! Duh! =-X

This a very nice dersign. Prints well and is a good test of overhangs.

Is just my printer or is the hole within the gear too large? I'll just wrap some tape around the ind of the bolt to let it friction fit.

Well, it could be the printer. I made mine from the exact same STL and it's a pretty tight fit.

"I'll just wrap some tape around the ind of the bolt to let it friction fit" too... Printed on Makerbot ToM. Nice tool, thanks.