Wednesday, April 19, 2017

First project done on CNC


Although I finished CNC build, the whole CNC design-production flow is still new to me. I want to test the flow out on a small scale project before moving on to big ones.

My daughter have potty in her room, and we keep a roll of toilet paper near it, and it always roll around and make a mess. I saw this cute animal shaped tape holder online that I really like. from the picture it's hard to tell what is the mechanism it load/unload the tape. So I have something in mind to have a wedge at the tail to lock the rear leg board in. The design is pretty straightforward. it has 3 pieces,  one for the head/body, one for front leg, one for rear leg. I also designed the joinery into the model, the idea is to minimize the post process off the CNC.


Since it's more of an experimental project, I played around with different CAM options just to see the they result. The simulation feature in Fusion360 is really handy for me that I can visualize the cutting without damaging the tool.




Even though this is a very simple design,  it took me half day to draw it up and create a tool path, export to Linuxcnc and setup the stock and get cutting. I was pretty happy with the first attempt:
pros:

  • the fit was perfect, actually a bit on the tight side.
  • the cutting time is very fast, I didn't time it, but around 15 mins
  • almost not tear out
cons:
  • The fit was a little too tight, I made the male part exactly as female part, I think when it was cutting, the cutter compressed the wood a bit, so the size is 1-2 thou larger than what's spec-ed out in CAD, I can compensate that in the future.
  • there are some bur on the surface, but easily cleaned up with some sanding.









I cut the slot on the tail on a table saw with tenon jig, and created a wedge to lock the rear board in. The joinery fit together so tight, I didn't bother to use any glue. I spend about 15 mins on sanding and put on a light layer of oil/wax and it's done.

Tape holder

Emma loves doing crafts, and tape if a tool she use a lot. I always want to make a cute tape holder for her. I prototyped with some ...