Posts Tagged: Projects

3D-print updates

So… now I have 2 3D-printers. After I got my monoprice mini delta about a year ago, I had some fun with my first 3D prints but clogged nozzles, adhesion problems and the printer printing plastic-wool in the air became more and more frequent and frustrating. I looked into the Ender3 Pro and together with my brother, gifted one to my dad for his birthday. His first prints worked out of the box. So when there was a good offer for the Ender3 Pro just the morning after my mini delta had a clogged heat-throat again, I bought it. Setup took less than 1 hour and besides some parameter related stringing issues, it worked like a charm straight from the beginning.
Like every good 3D-printer owner, I’ve printed many upgrades but also some fun or useful things – and optimized my ‘plane phone holder’.

3D printing a plane-phone-holder

Ok, technically this is a tray-table-phone holder. But it’s most useful on budget airline flights so you can enjoy your netflix-movies from taxiing to touchdown since your tray-table stays folded up. I’ve started with a fixed design for my Phone size and iterated to an extendable, foldable phone holder. I’ve used different revisions on flights from Eurowings, WizzAir, Ryanair (the magazine-pocket in the table-less seats works as well) as well as trains.
All printed on a Monoprice Mini Delta (my first 3D-printer) with different settings and different PLA-Filaments. Print-time for the last model is ~2h20min but includes a raft and massive support on edges and holes.
an M3 10/12mm screw and self-securing nut is required besides a rubber band.

Mini-Load – a resistive load for testing and prototyping

When developing electronics, it can be useful to have a way to draw or measure a specific current. While professional digital loads are quite expensive, a high-wattage resistor is sufficient in many cases. To have a small ( 16,5 x 10 cm), universally usable resistive load, I ordered a selection of resistors that allow me to draw commonly used currents like e.g. 50mA, 100mA, 200mA, 0.5A, 1A… for the common voltages of 3.3V, 5V or 12V. Additionally I included 0,1 Ohm resistors as shunts for measuring the current. To facilitate the combination of the used resistors to the desired total resistance, I placed the terminals at 19mm to use existing lab-socket jumpers and decided to connect the left & right resitor permanently. While this has the drawback of not allowing concurrent use for 2 outputs at the same time, it reduces the amount of required cables as well as plug/socket and cable resistances and inductances.

Costs ~ 55 €
Time ~ 3 h (excl. planning 😉 )
Materials used:
– 2x resistors WD25 (25W) 0,1 Ohm [5 €]
– 2x resistors WD25 (25W) 1 Ohm [4 €]
– 2x resistors WD25 (25W) 3,3 Ohm [4 €]
– 4x resistors WD25 (25W) 10 Ohm [7 €]
– 4x resistors WD25 (25W) 100 Ohm [7 €]
– 1x aluminium heatspreader 160 x 100 x 40 mm [ 15 € ]
– 2x aluminium stripe (320 x 10 x 2mm, bent with 90° angles as 10-70-160-70-10 ) [1,5 €]
– 1x aluminium stripe (250 x 10 x 2mm, bent with 90° angles as 45-160-45 ) [0,5 €]
– shrinking tube for isolation of the ‘feet’ [0.5 €]
– 40x short self-cutting screws (e.g. 9,5 x 3 mm) [2 €]
– 21x colored 4 mm lab-plug terminals [4€]
– solder-wire & desolder-wire (or some fine copper-mesh / wire)
– thermally conductive adhesive tape (double sided) [4 €]

– drilling machine (preferably with a stand for 90° angles)
– soldering iron
– scalpel / cutter / scissors for the tape
– Isopropanol as drilling lubricant
– 2.5 / 8 mm drills (preferably sharply cut, cobalt coated drills)