Printing with ABS
The most important advantages of ABS are impact resistance and toughness. Lego is made from ABS. It will also not deform in hot water, compared to PLA. On the downside ABS is hard to print. You need very hot printbed (around 110 degrees Celsius) and Kapton tape, so the first layer will stick properly. ABS can also warp and curl. There are also other issues in the Marlin firmware that need some attention.
Building Volcano Bowden extruder
If you are impatient and don't want to wait too long for your print to finish you can look for a solution in the E3D Volcano hotend. It is able to extrude filament a much greater speeds than a normal (V6) extruder. But it comes at a price of sacrificing the print quality.
LUT - Programmable logic gate
Altera Quartus on Mac OSX
One of the disadvantages of Altera Quartus II software is the disability to run natively on a Mac system. Luckily there are ways to get around this problem.
Leaking hotend extruder repair
It can happen that molten filament can leak from the hotend. This usually happens when there is a gap between the heat break hotend throat and the nozzle. This is the result of poor assembly of the extruder's hotend part.
Electronics theory #1: Electricity
The first step in electronics is understanding the concepts of current and voltage. There is a hydraulic analogy that helps to understand electricity, but here we will try to cover how it works on atomic and electron level.