Replacement K'nex chain link
Replacement K'nex chain link
Published 2018-01-11T10:51:27+00:00
My son got a roller coaster K'Nex kit for Xmas and of course by the time he put it together he had lost several links of the chain that made it work. Rather than order some more I went looking for a part to print... and while I found a lot of K'nex pieces I did not find the chain link. So, of course got out the calipers and got busy in fusion 360 and after about the 4th iteration I got a link that works. Not sure how well a complete chain of these would work as they have significantly more friction than the real ones. But 8 of them in a chain over 100 is working fine.
Version 5 update:
Version 4 links to the original pieces a bit better but is bad at linking together, Version 5 is pretty good at linking to each other AND the originals... seems a touch weaker though. Working much better on the toy... also interspersed them at 1 original, 1 replacement.
Printed on Prusa Mk2S, Prusa Slicer, .15 layers using supports in MakerGeek PLA. temp 215 first layer, 205 for remaining. Default speeds.
Time to print and material quantity based on 10 units at a time. Not sure if 1 at a time would print very well, would be very little time for cooling. May work but I haven't tried it. Recommend 10 at a time minimum.
You do need supports and that makes clean up of the parts a pain. Not to bad if you have flush cutters. If anyone is interested I can make a version without the center guide bit which makes it require supports. Otherwise I imagine it could bridge the link and it would make it a LOT easier to make a bunch of these. Makes the links a lot weaker as they can squeeze. With this there it becomes pretty solid if you are pushing in on it.
Date published | 11/01/2018 |
Time to do | 30 - 40 minutes |
Material Quantity | 4g per 10 units |
Dimensions | ~20x6x10mm |
Technology | FDM |
Complexity | Easy |