Haydn Huntley’s MagBalls and MagBallArms for Delta/Kossel 3D Printers


My adapters for the Predator effector, printed on a Photon.
https://www.thingiverse.com/thing:3880977
Photo and print courtesy of Tai Hromnak

My Kumu-3D printer.
An unusually rigid printer.


More Photos

Note: Due to COVID-19 we have to use more expensive mail than usual.
If you order together with a friend, often the postage stays the same for two
sets in a mailing tube, and sometimes it is possible to fit four sets in one tube.

Description Examples Price US Priority
Mail postage
Priority Mail
Express International
High-precision MagBalls 12 for $18 $8 $45-$75
CNC’d Delrin rod ends 12 for $15 $8 $45-$75
N52 NdFeB magnets (each one tested) 12 for $24 $8 $45-$75
215mm set of arms Mini-Kossel w/170-190mm bed $85 $10 $45-$75
288mm set of arms: Kossel w/225-240mm bed $85 $10 $45-$75
304mm set of arms: Kossel w/250mm bed $85 $10 $45-$75
360mm set of arms Kossel w/300mm bed
DC42’s Precision Kossel
Kumu-3D
Ultibots D300VS
$90 $10 $45-$75
400mm set of arms TEVO Little Monster w/340mm bed $115 $10 $45-$75
440mm set of arms Anycubic Predator w/370mm bed $115 $10 $45-$75
Custom length set of arms up to 600mm $115 $10 $45-$75
10mm CF tubing instead of 6mm extra $60

Email haydn.huntley@gmail.com for MagBalls, magnets, and extremely carefully assembled, precisely measured carbon fiber arms.
I test and measure each set of arms. The magnets in the joints have a tested holding strength on a MagBall of at least 1.5kg.
The arms in a set match lengths within 50µ, according to my calipers, and typically they match within 30µ.

All sets of arms include MagBalls, N52 magnets and CNC’d Delrin ends.

Lubrication: I’ve heard that the best is SuperLube PTFE, which I now include a small tube of.
I’ve also had good results with bicycle chain lube, which is waxy enough to stay in place, such as White Lightning Easy Lube

John Giardino wrote up a guide on converting the Anycubic Predator to use MagBall arms, using the stock effector and controller and my printed adapters.
Many people have also done it using either an SKR or Duet controller, which is straightforward.