Thursday, April 4, 2019

Time for a ball screw printer

While thinking about how to upgrade my Delta printer, I was considering the viability of using ball screws instead of pulleys and belts. However since the movement of the carriages is sometimes 4 times greater that the actual speed of the print head, this seems like a bad idea.

That lead me down onto a path of comparing the existing printer designs.
  • Cartesian: The classic, but moving the bed just creates unnecessary acceleration artifacts.
  • Delta: Looks good, but the aforementioned speed issue, salmon skin/moire and the extra z height cause some issues
  • CoreXY: The underdog, seemingly combines the best from the previous designs, however the long belt path wont be good in combating acceleration artifacts.
  • Cross-Axis/Ultimaker: That could be the one. No moving bed, short belt path and a contained frame, make this a promising option.

With a cross axis design, we would only need one ball screw per axis. With the rigidity we gain from the ball screws we could probably get away with not using a bowden extruder.

That leaves just calculating if we can get cheap enough ball screws and if a normal NEMA17 can drive them fast enough...



This looks pretty much like the design I would go for.

Sunday, March 31, 2019

Reload, reset, relaunch. New content coming

I admittedly slacked of a bit, but now I feel motivated again.

I want to launch two new series of content.

Useful Products:
There are not many useful 3D printed products out there, but they do exist. Until we find a killer app for 3D printing, we have to start somewhere. Everyone is invited to find products or applications for 3D printing, so we can collect them and really show what 3D printing is capable of.

Advanced technical testing:
Beyond the China kit printers, there are still lots of interesting developments and ideas to test to make reprap machine better. I want to answer questions like what is the relationship of actual extruded print volume to commanded volume?, are 0.9 degree stepper motors worth it?, should I counter balance my effector? or are TL smoothers a scam?
Of course some questions I cant completely test out but at least I can try to find arguments from all sides on forums etc. to give some interesting insights.

In addition I want to document my printer upgrade progress and aforementioned testing on Youtube, which also allows me to give back to the community. I thought I could start a regular lifestream, where we/I can fix some printer issues life. I know Thomas Sanladrer sometimes does stream under the #3D-Doc, that seems like a cool idea to me.

PS. Is anyone interested in developing a ball screw driven cartesian printer? :D

Sunday, May 17, 2015

Pump clipper for Balloonistas

I love my balloon folding but having the pump either under my arm or somewhere on a table where I can't reach it, annoys me. So I 3D printed me a little clip that can hold the pump while I'm busy with the balloons.

I tested this last year successfully and now made a version that fits our pumps even better and is practically unbreakable* since its printed with a rubber-like bio-plastic.

My WD40 bottle is just to demonstrate the workings. I can jump around without it falling out.








*If  you manage to tear it apart you get a new one and an extra price :D

Tuesday, May 5, 2015

Sunday, January 25, 2015

Tour de Fork


Late summer lunch - 3D printed objects from Tourdefork on Vimeo.

I recently started printing kitchen item myself, so I'm absolutely loving this.

Check out more designs here.

Monday, December 15, 2014

Slic3r vs. Cura

I tested out Cura with my new set-up and I'm positively surprised about the results.
Slic3r is working well but there are some parts of the Gcode generation which leave some ugly artefacts. Especially the change from perimeters to infill always leave a mark on the outside.

Slic3r, still having troubles generating clean perimeters
















There is still an argument to be made about Cura missing a lot of the fine detail function. No acceleration settings, no manual control and the simplification of giving only a outer wall thickness and not a number of perimeters are a bit to simplistic for my taste.

But the results speak for themselves.
Except for the little blobs, degenerated layer and bigger gaps in the perimeters didn't happen in the Cura printed (golden) parts. I will give Cura more tries in the future.

Cura, overall much more consistent look