Instructables
loading
loading
Picture of Reprap Mendel K'nex Frame
100_1397.JPG
100_1398.JPG
100_1399.JPG
100_1400.JPG
100_1402.JPG
100_1403.JPG
100_1404.JPG
100_1405.JPG
100_1406.JPG
100_1408.JPG
100_1409.JPG
100_1413.JPG
100_1414.JPG
100_1415.JPG
100_1416.JPG
100_1417.JPG
100_1419.JPG
100_1420.JPG
Reprap is an open source project to create a 3D printer that can make its own parts, essentially printing itself. While looking through the RepRapWiki one day, I found the FTIStrap which is a Repstrap made out of fischer technik parts. I didn't have any access to fischer technik parts, so I decided to recreate the Mendel frame out of k'nex.

The overall goal of this project was to create as much of the mendel frame and chassis as possible, so you would only have to add motors, belts, and electronics. Additionally, while k'nex would not be suitable for long-term use, they should be good enough for enough prints to create a set of parts for a reprap machine. I tried to make as much of the project out of k'nex as I could--the only exceptions are the nuts, aluminum tape, threaded rods, and hot-glued lego gears (I had to grind out the central hole to have them fit on the threaded rods) on the z-axis.

An issue that I had with the final design was that since the top joint of the frame was not at a 45 or 90 degree angle, it didn't fit perfect, causing the z-axis rails to flex a bit. Another thing to note is that since the build platform is a plastic, blue k'nex plate, it would have to be covered with a heat resistant material before actually printing.

(I apologize for the lack of notes on the photos. I tried firefox 4, chrome 10, and safari, and none of them were able to properly create and save notes on the images.)
kaelumhasler4 months ago
do not put electronics in that. build and design your own quality wooden frame. its not very difficult. it will save you lots of heartbreak when that knex machine destroys itself. the plastic will soften due to the stepper heat and the hot end heat and it will warp under the tension of the gt2 belts.
dombeef3 years ago
Any new news?
You could even add gears and chains for the x axis kenex sells them with roller coaster sets
lmaya4 years ago
very cool but are you going to actually turn it in to a working mendel
Superchef (author)  lmaya4 years ago
I have to finish obtaining electronics and motors before I can turn it into a functioning repstrap.