Rechargeable USB Lithophane Box / Cubewith power bank electronics

myminifactory

A compact cube for four lithophanes (93mm x93mm x2.5-3mm or 100mm x 100mm x 3-3.5/4mm) - other standard dimensions will be added soon. Powered by electronics and a battery taken from an inexpensive powerbank. This allows it to be used with the battery, or with a USB power supply (1A). I will add pictures and detailed descriptions next week. For now, this is more of a placeholder with STLs. The Top_100mm and Bottom_100mm files are for lithophanes with 100mm edge length and 3-3.5mm thickness. The Top_100mm_4mm and Bottom_100mm_4mm have 4mm clearance for thicker lithophanes. The Top.stl and Bottom.stl are for 93mm edge length and 2.5-3mm thickness. The others are universal. Printing: Use the test-tool.stl to determine the correct width to print. Print the Top and on-off-button upside-down - I will change this with the next export. Non-printed components used: LEDs: Four SMD LEDs, Osram LCW JNSH.PC-BUCQ-5H7I-1 (no longer available). Relevant specs include: * Package/Case: SMD-2 * Illumination Colour: Cool White * Wavelength/Colour Temperature: 5000 K * Luminous Intensity: 2590 mcd * Viewing Angle: 120 deg * Lens Colour/Style: Tinted, Diffused If - Forward Current: 20 mA Vf - Forward Voltage: 3.05 V Powerbank: https://www.amazon.com/2600mAh-Portable-External-Battery-Charger/dp/B00NIIR194/ USB-Breakout: https://www.amazon.com/MonkeyJack-Female-Adapter-Converter-Breakout/dp/B071VZ2119/ Resistors: For the LEDs, I used four 100Ohm 1/4W resistors. The resistor values depend on the LEDs used. You can calculate them by subtracting the LEDs' forward voltage (Vf) from the 5V USB voltage and dividing it by the forward current (If) in A. In my case: 5V(USB) - 3V(Vf) = 2V, then divide by 0.02A to get 100Ohm. Screws: Five M2x5mm screws and four 2x10mm pan head wood/universal screws.