First toolchanger test on cartesian 3d printer

This is my 3D printer which I am slowly converting to a toolchanger one. The 3D printer started out as an BotObjects Prodesk 3D. This printer literately could not print as shipped to the customer. I redesigned everything to get it to work. I have been printing reliably with this highly modified printer for a few years. The tool changing concept is a new addition to my trusted 3D printer.
The printer normally has a cover on the top and bottom.
Please be aware that I don't know of the system shown in this video is actually reliable and repeatable enough to print. I haven't printed anything with it yet.

[@globaldisaster1988]

That is awesome, more infos and videos please))

[@FrankyieFrank]

Thanks! I am still testing this machine. So for now, no more videos. The system is more problematic than I thought. Only last weekend I was finally able to pickup toolheads with enough repetitive accuracy. Using kinematics couplings vertically is not such a good idea.

[@andyfamily7184]

Was ne geile Idee!

[@DannerD3H]

Awesome! I am designing something similar myself! What are you using to lock the tools? is it a cable driven thing or is it just a small actuator? I really like this method over the e3D twistlock style.

[@FrankyieFrank]

It is cable driven by a stepper with gearbox on the back of the printer. There is a spring inside the head which actually holds the tools in place by use of the T bar. The cable pulling systems is only used to release the tools. Be aware of the force necessary to pull this cable. I am barely able to pull it my self! Friction is your worst enemy in this system. Both for the cable pulling systems as for the kinematic coupling. The system shown in this video does not work. Please look at the more modern video which shows a different T bar for locking the tools. This T bar doesn't have any friction but is more fragile. I also use some friction reducing tricks in the cable pulling systems but I haven't made a video with these fixes. Theoretically it is better than the e3D solution. It is however surprisingly difficult to get this to work. Yesterday I printed my first three color print. That is how long it took between this video and getting a somewhat problem free system. This is one hell of a project!

[@DannerD3H]

@@FrankyieFrank Thanks a lot for the info!!! It is going to be a while before i get to the tool changing part. I am currently just finalizing the XY motion system. It is a crosbar like yours but with rails and 2 motors pr axis instead of the shaft from side to side. A little ekstra challenge having to lift the tools out of the way, but deffinetely the ultimate sulution compared to a corexy with long belts IMO. Yeah a reliable tool changing mechanism isn't easy to design... even just a basic 3D printer is hard to design well! :P

[@FrankyieFrank]

@@DannerD3H That is going to be a beast of a 3D printer! Some advice regarding the XY motion system. Stepper motors can only deliver torque when they are not at there desired position. Therefore a stepper motor 3D printers always has some position errors which is visible in the finished print. The best way to reduce these errors is to reduce the friction in the XY systems as much as possible so the steppers are closer to there desired position. Again, friction is everything. Fun fact about the elevator system for my tools. It has a double function. Of course it gets the tools out of the way, but it also lifts the cables of the unused tools above the cables of the used tool. Cable management is brilliantly simple and compact this way.

[@DannerD3H]

@@FrankyieFrank ​ Haha yeah it will be a beast :P Yes Steppers have their limitations.. I may look into odrive, but will try with regular nema23's for the XY first. I will be using linear MGN12 rails for almost everything including the XY system so friction is gonna be as low as can be. Will also use bearings with metal shields instead of rubber seals. but thanks for the heads up! Didn't considder that functionality of the elevator xD Hope to see mor videos on this printer from you! :)

[@FrankyieFrank]

@@DannerD3H I will make some more videos in the future. For now my focus is getting the machine working properly. :-)