This would go in the Q&A, but I don’t believe that it’s open yet.
Does anyone know the true diameter of the pipe the cubes are made of?
According to the VEX website and Appendix A, it’s 1.75", but the manual says approximately 2". I suppose that approximately could account for even as much as .25", but it seemed wrong.
We will be making some cubes from PVC today and needed to know what to buy, for now I’m going with 1.75".
Yes I thought this was odd as well. The manual says 2" diameter but the CAD files are at exactly 1.75". Usually when the CAD file is at that exact of a number, that’s what the game piece actually is. Obviously teams should design for at least .25" error anyway (I would do more then that) but it would be nice to know if the manufacturing spec is 1.75", and if so have the manual updated.
I guess the most important part thought is the 8" overall cube, which remains true either way.
We hadn’t had much experience in PVC and expected things to work out much better than they did.
We found some fittings that would work for corners, but the diameter was much too small.
In the end, we determined that we would be saving very little money by making our own and decided it was too much hassle to try and make our own. The price difference was not worth the time we would waste building them and having something not exactly similar in size/weight to VEX’s. We’re just going to buy the small kits from the VEX website.
Sorry for any confusion. The correct nominal dimension for the diameter of the “cube pipes” is 1.75". We will get the manual updated accordingly.
Please note, there will be some manufacturing variance in the pipe size.
To help ensure everyone has access to the “official competition” game objects, this year’s VEX Robotics Competition Welcome Kit includes (1) Cube and (1) Skyrise Section. Hopefully teams that do not wish to purchase the official objects can use this sample cube to build additional practice cubes.
The way we made the pieces of the cube in autodesk inventor is:
Making a sketch of 1.75*1.75 square
Extrude it by four inches
On the solid, make another two squares and extrude them out 2.25 inches, making basically a “squared” cube corner
Add fillets into each single necessary edge, fillet diameter is 1.75/2=0.875
And there you go, naturally spherical corners generated by three circular cylinders.
Finally, shell it. Make insert structures if necessary, but do it before shell.
Ours is still being printed out… since one corner takes twelve hours to make, probably next week I will post a picture of my 3D printed cube.
Edit: it is supposed to be fillet radius, not diameter. My bad.
Hi Karthik when do you think they will be available in the UK ? Because we are considering ordering new parts now and the game objects later but if they’ll arrive in a week we will just wait and order everything at once.