Kossel based magnetic effector + self-locking carriages (10 mm magnets) by docpayce

Last crawled date: 3 years ago

I wanted to upgrade my Folger Tech. Kossel 2020 to magnetic rods, but found that most solutions on thingiverse either use steel ball studs on the effector (which I dislike a bit) or redesign the effector/carriages in such a huge way that I could not use all the Kossel-compatible accessories I already printed out (magnetic z-probe, fan mount and alike). So I took the very base Kossel carriage (self-locking type) and effector and JUST made it accepting cylinder shaped magnets. Everything else is as close to the original Kossel design as possible. In fact, the .scad files should even be compatible to JCRocholls github Kossel (https://github.com/jcrocholl/kossel).
I hope this helps others! :)
About the magnets:
The STL's are designed to accept cylinder-shaped magnets with 10 mm diameter and 5 mm height (the hole, which accepts the magnets, is 4 mm deep). Be sure to get axially magnetized magnets, NOT diametral ones (those are magnetized perpendicular to the rotational axis). I prefer the ones with ~4 mm bore diameter, as they give the best compromise between holding force and inhibition of sideways movement.
The magnets are angled at 31° (that was ideal for my setup) and have a separation of 45 mm. If you want change any of these parameters (in addition to Delta_effector_offset, hotend_radii etc), pls check out the .scad's. Should be pretty self-explanatory.
Update May 4th 2016: Added .stl's of the cups for mounting the steel balls to the carbon rods. Designed for 10 mm diameter balls and 6 mm diameter rods.
Update May 12th 2016: Up to now I wasn't very happy with the way, the magnetic cups on the effector printed (bunny ear syndrom). But on the other hand I didn't want them to print with a completely flat bottom, as that would make the inserting of a magnet a pure torture (for both you and the effector). I came up with a pretty easy solution: There is a vise helper now, which attaches to the effector magnet cups during prying in the magnets. Easy solution, works VERY well. If you downloaded the files before May 12th, pls redownload. The new version of the effector + vise helper is much better imho.
Update May 24th 2016: There is now also a version to accomodate for magnets with 12 mm diameter, check it out: http://www.thingiverse.com/thing:1584513