Mini dome with pins - Icosahedron
Description
This is a minor derivative of thingiverse.com/thing:26860
A quick and dirty hack to use pins for hollow connectors like straws/pipes/bamboo
See the thingiverse page for instructions and
desertdomes.com/pictures/dome/2vdiagram.gif
for assembly.
Look out! If you print too many connectors you may find yourself under attack from alien pentacles and hexapods (see pics of the invasion i had to fight off). Hint: the one with the extended proboscis is the leader!
Instructions
Before printing: measure your straws inner diameter and change the scad files:
sd (last line) is stick diameter, set this to slightly less than the inner diameter of your straws/pipes/bamboo. 4.3 works for my 5mm straws with my reprap. Compile (F6) and export stl.
Print one and test that the straws fit snugly, adjust as needed. When they fit adjust both scad files. You need
* 20 x Hexa-connectors
* 6 x Penta-connectors
I used slic3r to print these on three plates. There is some bridging so it helps if your printer isn't awful at bridging but it needn't be perfect.
* 35 x long straws
* 30 x short straws
I had bendy straws so I cut the long ones just below the bend. My printed connectors are approx 2.5cm point to point and my long straws 16.5cm. So I entered 2.5+16.5=19 into
desertdomes.com/rev2calc.html
as my A length. The page says B is then 16.8 so I cut my short straws at 16.8-2.5=14.3cm.
It turns out I'm human so after all those calculations I just eyeballed my short straws as approximately 2cm shorter than the long ones! :-)
For assembly follow this diagram
desertdomes.com/pictures/dome/2vdiagram.gif
or use my main picture. Green and blue are the long connectors A, red and pink the short ones B. When assembling the X on top of the six-pin connectors indicates the four pins that use the long A connectors.
The pins are slightly tapered to ease printing and straw insertion.
Note on license: I chose the same license as the immediate predecessor to this derivative, IANAL, let me know if I should've chosen something else.
You must be logged in to post a comment.
I think these can even be made with a smaller 'body' to make reproduction faster and make them even use less material.
I don't know if you're ever heard of the 'Operation Manual for Spaceship Earth' by Buckminster Fuller, but in his view on finite resources on this planet, and his implementation of the geodesic dome into architecture, I'm sure he would love to see this modular piece re-designed to use the least material possible ;)
Great design nonetheless, I will print a few tonight, actually, this part is what inspired me to build my own 3D printer, so thanks for the inspiration t00tie!
If you really can't use openscad and need another size ask nicely and I'll probably help you. If you make one please share pics but remember, I'm not the one who deserves credit here, C60, EFFALO and obijuan did all the hard work.
License

I'm trying to slice these parts, but they only show a cross when I slice them in slic3r, tried multiple settings, but it just only shows crosses to print. Do you know if there is an error in the files?
They slice just fine in slic3r 0.9.9 now. They sliced just fine in the version I used when I first made them too. I use 3 perimeters and 40% honeycomb by default.