latching magnetic toolchanger

[@liamventer]

Really clever design. I keep on thinking of alternatives and then coming back to your elegant design.

[@jacqueslambert6627]

very nice

[@split3d610]

hello, really nice setup. how is it after some time working? any issues?

[@philwilson8296]

Hi, glad you like it. I've been very pleased with it. It really hasn't missed a beat since the day I got it going. The magnets make it very tolerant of any misalignment. To be fair it hasn't had real torture testing with millions of changes. I've just got on and used it for normal personal use, and it's kept working. The materials that I used for the latch were hardened gauge plate for the pawl and unhardened silver steel pins, all nicely polished. No signs of wear yet, despite virtually no lubrication. In the past I made a clock escapement with the same bit of gauge plate, and that really has done many millions of actions! - although contacting brass. I don't think it is on the video, but I have also used a direct drive head. It's a bit bulky, and needs improvement, but the magnets have held the heavy stepper motor and feeder ok. Good luck if you make one.

[@ameliabuns4058]

how does your latch work! can you give any info or files? I have a space constrain issue with mine since I slide my tools right on a pin then pull out it takes a lot of space. this seems way smaller and amazing! EDIT: I figured it out! when you push it more it falls out of the metal latch entirely then you just drag it out from the bottom! it'd be hard to 3d print it tho

[@philwilson8296]

Thanks. I'm glad it's inspired you. It's proving very reliable. I've posted pictures and links to my cad files on the duet3d forum: forum.duet3d.com/topic/9392/latching-magnetic-tool-changer. Let me know you make one. Good luck

[@philwilson8296]

@@henn1nk I'll message you

[@danielkratzer3580]

Dear Phil Would you mind sharing the spring detail for the latch?

[@philwilson8296]

Certainly. Have a look here: forum.duet3d.com/topic/9392/latching-magnetic-tool-changer?_=1622553017159 where I posted some detailed pictures. I wound the springs by hand from 0.35mm diameter piano wire. The finished spring measured 5mm diameter, after winding around a smaller arbor - probably about 3-4mm dia. When designing springs you can do a load of calculations, or just experiment a bit ;-) Either way, the spring force is not at all critical, because all it has to do is return the pawl to position after the print head is parked/picked up. The strength of the latch comes from the geometry of the pawl. hth

[@danielkratzer3580]

@@philwilson8296 Thank you Phil the main issue I had was that the spring lost tension but I fixed that with a complete perimeter clamp.

[@cdl1701]

Awesome! would you mind sharing your configuration files for the tool pickup and docking? I am working on a printer very similar to this right now.

[@philwilson8296]

Thanks, glad you like it. Yes, I'm happy to share my config files. They are for a Duet 2 board. I'm sure they won't be plug and play for you, but they may get you going. I learnt as I went along, so there are quite possibly other/better ways to set it all up. Is there a way to message you on youtube? Otherwise, if you have to post your email here, I'll delete it afterwards

[@SebastienChedalBornu]

Hi what are the magnets you use ? you don't mention them in the duet forum. (i want to know the force for each magnet or if you still got the link) thanks a lot.

[@philwilson8296]

Hi. This is what I used: 8mm dia x 4mm thick N35 Neodymium Magnet - 1.47kg Pull. link: www.first4magnets.com/circular-disc-rod-c34/8mm-dia-x-4mm-thick-n35-neodymium-magnet-1-47kg-pull-p6222#ps_0_6417|ps_1_6658. They have worked perfectly, and even manage to hold a print head with quite a large direct drive attached, which I was surprised about. I was a bit worried about the magnets losing strength in the heated chamber, but so far so good. Good luck with your build

[@SebastienChedalBornu]

@@philwilson8296 thanks a lot. I'm adapting your system to fit a BLV MGN cube printer. (And I want to use with direct drives like hemera/matrix/busy h2 extruders)

[@SebastienChedalBornu]

@@philwilson8296 any problem with temp reducing the magnet power as your printer is closed ?

[@philwilson8296]

@@SebastienChedalBornu Your welcome. With those sort of drives you should be able to make the print heads much more compact/lighter than my version

[@philwilson8296]

@@SebastienChedalBornu Not so far. The enclosure is heated for when using high temp filaments. It then runs at about 60-70deg C which is a bit high for the magnets, but they seem ok. However, they are cheap and not difficult to replace if they do weaken. I have had fans fail at that temp

[@bullseyedesign9788]

Awesome!!

[@janskupnik7595]

Nice system, I would like to make something similar. Could you please share photos of motion system and configuration files?

[@philwilson8296]

Hi Jan. Glad you like it. I have posted a lot of details on the duet forum forum.duet3d.com/topic/9392/latching-magnetic-tool-changer You'll find some pictures and a link to my cad files. The cad files are a mess, but its all there. Good luck with your build. Let me know how you get on