Meetup 20181129

We had a very full garage this week! Lots of people, interesting projects, even though we had loadshedding from 8pm to 9pm.

Full Garage

I did a few labels on my masking tape labeller, after having found a way to make it run consistently without first having to recompile the Arduino code.

Steph cut out the wings for his pico stick (copied off my stick’s wings) and worked on his 7-segment display.

Albert and Stefaan (2 learners from Paul Roos) visited to talk about some projects they were thinking of doing. Later, they disassembled one of my old hard drives. Hopefully an enjoyable evening for them.

I helped Reuben go through the settings on his Marlin installation to get it to work with the Trinamic 2130 drivers with SPI. The extruder (non-spi) works now, but not the rest.

Bouwer (first-time visitor) wanted some help to design a circuit that would sound a buzzer if more than a certain amount of pressure is put on a mat made with Velostat (interesting material!). Otto talked him through a circuit and the tradeoffs he needs to make.

I talked with Jan a bit to sort out details for the belt tensioning on the Maslow, and he was busy with the hardware wiring looms.

Otto was working on getting his laptop set up with all the tools on Ubuntu. Looks like his Salae clone does not work on it yet. We tried looking at the SPI signals on the 3D printer board.

Otto also got an Itsy Bitsy set up with 3 serial ports, talking to an Arduino. This is for a project where he needs lots of serials. We discussed the pros and cons of Micropython.

Kim popped in for a few minutes. She had started growing cell cultures on a silicon mold she made from my 3D-printed surfaces, to see if they would follow the grooves caused by the layered build process. This should be interesting…

Altogether a really nice evening.

Meetup report: 22 November 2018

Yes, these are just dry reports of what happened, but they provide a kind of archive of the goings-on at the Thursday evenings and gives me a way to track attendance and what’s happening.

I found a pic of the rendering of the vase, so here it is:

Scorped vase

Last week:

Steph got some 2mm Depron from a local hobby shop, and we talked a while about the ideal material and setup.

Kolijn continued with the design for the Lora signal strength tracker, and we went through options for getting the cases machined consistently. The plastic box is about R12, but would cost over R100 to get the holes in.

Danie came to chat about his art car project for AfrikaBurn. We tried to figure out how many controllers he’d need and how much power it would require. Lots.

Kim popped in for a short while to say hi.

This week:

Last Saturday and Sunday I messed around with getting a LED to sense light levels, and then average that out and get a moving envelope of the variations, so that I can communicate with an Arduino using flashing lights. This is still in a very early stage, but I can now reliably detect a flashing light at about 1Hz frequency, so it’s going to work. Thursday evening I found out that the capacitance (or something) of my hand approaching the board also has a big influence on the voltage levels, so we might be able to do something with that too.

SOS in Morse code, detected via LED

The MaslowCNC frame is built! Jan got the belts this week, and came to pick up my spare wood to be used for the build. The machine is to be housed against Otto’s garage wall, so I could not help build.

Maslow CNC frame up on the wall, no moving parts yet.

Steph had a four-character 7-segment display, and got it to display a scrolling ‘Hello’ by putting together pieces of code found from various examples on the web. Pretty awesome!

ello, because 4 segments

Reuben had the new trinamic drivers with SPI control installed, and spent some time getting the Marlin settings right. In the end, the motors did not run. Time to take a step back and get it running using the non-SPI setup, then we can sort out if it’s a setup problem or a hardware issue.

Reuben getting the settings figured out

Altogether, a really nice evening.