I have a NOMAD and have been teaching my cub scout about the fun world of CNC. He wants to try to use CNC for his pinewood derby car but that is way out of my wheelhouse to do 3d. I am only comfortable with 2d right now. I wanted to reach out to the community to see if there are any ideas to help? I have Alibre and Carbide Create for my tools. I do want my son to do the modeling and we started in Alibre but we both got stuck on how to create the wedge design. I will also post this in the Alibre community to see if there are suggestions on ways to help him and I learn 3d.
Then, once you have the design in 3D, export as an STL and import that into Alibre Workshop to make G-code to cut on the machine.
Another option would be to just make a fixture to hold the wood at an angle and then face it off (or mark the four sides and cut the block on the diagonal to avoid the need to remove so much material, then you could use the offcut to support the part you wish to shape so that the top is level).
Or, hopefully someone will come along here, or on the Alibre Forums and assist you w/ Alibre — as noted, while I was modestly successful w/ it at first:
I was completely stopped on trying to use the spline tool due to a corrupt preferences file, which wasn’t pointed out to me on the Alibre Forums for the better part of a year.
Another option would be to source a V endmill or chamfering tool of the correct angle and model the cut at that angle in Carbide Create using a series of parallel lines w/ no offset contours set to the correct depths.
Yeah, there’s something to be said for the old tradition of just doing it w/ a pocket knife (which is how I did both of mine, though on the first, I had a repetitive instance of cutting myself, washing my hands and bandaging them, to the point where when my mother came in to check on why the water was running for so long I passed out from loss of blood, necessitating a trip to the emergency room, but fortunately no stitches).
The Scout Leaders said I did really well competing against everyone else’s father.
Hey Jason, I think an easy work around for your difficulties in Alibre is to focus on the side profile of the car. Work from the left or right plane and draw the side profile of the car, then simply boss extrude to the final thickness. This way you can create the exact wedge shape you want as a simple 2d drawing.
In my side profile I included the wheel wells and driver seat. If you do not wish for these to run the entire width of the car, create them with an extrude cut after the extrude boss.
Good for letting the kid take the lead. I have helped with pinewood derby cars and the parents build the car and let the kid paint it. That defeats the goal of the kid building the car.
My son is 12. We use Tinkercad all the time together. It has a great tutorial and it’s easy for us to use. Not exactly Autocad, but learnable in 2-3 hours.
We have an Dremel 3d printer. He is printing up all kinds of stuff. He is also modifying Thingiverse.com projects.
The next step is to custom-design something for the Shapeoko!
