Monday, February 2, 2015

Electronic scale .. just because..

Bought a bunch of stuff on Ebay, here among: HX711 strain gauge A/D converters, 40Kg. load cells, 2,8" TFT touch display Arduino shields.

These items were all bought for different projects but screamed to be put together into a Arduino powered scale:

All components were just mounted on pieces of CNC cut plywood:
With this set-up I will be experimenting with different weight related issues such as:
counting items, mediated chemical recepies, food monitoring, paint usage ...

More to come on this.

Arduino source (as is!) for a couple of experiments

Induction heater

At FabLabRUC we have been experimenting with differnt kinds of metal casting. One of the methods is "lost PLA casting" where a 3D printed PLA model is covered with plaster and made to melt away when molten metal is poured over it.
Problem is that the metal (aluminium in this case) cools off too quickly when it contacts the plastic.
I wanted to find a method to keep the metal molten while inside the mold.
One solution seemed to be using induction heating.
A lot of people on the Internet seemed to have success with a simple induction heater circuit so decided to build one inspired by these:

A video (Danish) of an early prototype from FabLabRUC:
More about this heater and the casting process later..