Producing the first part for my hydroponic setup

So, today i decided to produce the first part for my hydroponic setup. The part in question was the Left mounting bracket for the tubes, here marked in red.

Since this part will need to handle both twisting and downwards pressure, i did FEA analysis of the part, and changed the design until i was happy with the result:

immediately after machining the part, i had to play with it to see if it was rigid enough. Needless to say, the part snapped. The problem was that i had not taken in acount the direction of which the grain in the wood is orientated.

Disapointed with todays result, i gave up any further work, and instead pimped my office-cactus with some ultrabrigth LED's and ate chocolate.

3D milling aluminium and stainless steel

This weekend i held courses in Fusion 360 at Bitraf. We started of with a course aimed for people without any 3D modelling experience on friday, then went trough some of the more advanced functions on saturday, before moving on to the CAM function and 3D printing on sunday.

On saturday i lectured about assembly in fusion, and the difference between bodies and components, and how to structure the file when building an assembly with moving parts. The case for this weekend was this machinist vise, as we then could use the model when we were milling on sunday.

After modelling the vise, we modelled a test case, 60x60x100 with some random topografy for testing out Fusion CAM's adaptive clearing. As we now had a 3D model of the vise, we could now easly activate collision detection, aswell as grabbing the necesary geometry for mounting the vise to our machine.

As this weekends goal was to experiment with 3D milling, we also tried some different finishing strategies. For aluminium, what worked best where a 6mm singleflute ballmill. Above is a rendered image of the vice, with the finishing toolpath projected on to it using gimp.

The machining process leaves a mess, but since i where using adaptive clearing, it's a uniform mess. All the chips are uniform, since the tool cut the material with a constant load.

I did several tests with different stepdown and stepover. For each test, i let one side be finished, while the other side still had the surface from the roughing pass.

I also machined a 50x50x50 block of stainless steel, this was the result:

This is the toolpath for the steel block. The model was produced by warping a hexagon along an the center axis. As the material was stainless steel, the stepdown was kept low at 0.2mm, but the feedrate high at 1600 mm/min.

The three samples sitting at my desk after a long weekend. i have now aquired the knowledge needed for producing my first injection mold.

Concrete casting workshop

Yesterday i and Christina Lewis held a concrete casting at Bitraf.
The workshop was meant to be a collective tryout of concrete as material for both art and technology.
We used a thin, low viscosity concrete, intended for use as garage floors.


We did two rounds of castings, in the second round, we added colour in the concrete. The color was a challenge in it self, as adding any substance to the concrete, alters its properties. The one i ended up using, is a pigment in powder form, normaly used for painting chalk walls

For the big candle holder shown at the intro, i milled a mold from building insulation using a 10mm milling bit for removing the bulk of the material, then finishing it up with the 6mm long ball nose.


For the small project that we did over the weekend, using a drill mounted spiral mixer in a bucket where sufficient. For the molds, we used the already mentioned machined foam block, as well as cut bottles, coke cans, crumbled paper cups, and 3d printed molds.

The 3D printed molds where especially interesting, as the low viscosity concrete capture every minute details from the print.

More results from the workshop:

 If you want to try this out yourself, have a lookout for the next workshop at Bitraf's meetup.