A friend who recently acquired a CO2 laser cutter for his school recently sent me a message. “What is the difference between a laser that will cut metals and one that won’t?”. I thought this is a good question, as the answer will help with understanding how to work with many materials.
In preparing a surface for paint / glue / thermal paste / soldering / whatever, there is one thing to remember. A normal finger print is of similar thickness to cling wrap (0.01mm). A thick (eg post pizza) print, where the ridges are no longer visible, is closer to the thickness of a sheet of paper (0.1mm).
Rule of thumb. If you would you would not be happy with this kind of material on the surface of whatever you are coating, remove your finger prints.
[Updated for arduino v1.6] This post is a huge set of PROGMEM examples (done as unit tests) which you can freely copy and paste into your work.
The readership level is set at those who are already familiar with the arduino PROGMEM documentation here and the use of the F() macro and __FlashStringHelper*
Its designed as a reference to save you the “lets see how to make this work” time and communicate common pitfalls. Search for the method you need to use, and see it running in working tested code
Managing arduino projects can be a nightmare because its hard to keep track of your hardware setup in your code comments. To enable easy documentation of pin assignments, I created a couple of ASCII art arduino pin-outs.
These come complete with ports, PWM and coms all marked. Simply paste as a comment into your code and marvel at your new found organisation.
Cabinet cooling hack. Because good entertainment units are still not heat dissipation savvy.
I needed some fan guards for my arcade machine and for a neat little entertainment centre hack. Playing around I made a fish-eye honey-comb screen that looked pretty good. The pattern has larger holes near the centre of the fan and smaller holes where it counts.
I have felt for a while that web searching is still an awkward thing from a Human Computer Interaction point of view. So I made a wish list of simple improvements that would literally turn my world upside-down.
Laser engraving text on acrylic / perspex does not create a lot of contrast. This leads to the subject of painting text on the acrylic. I have developed some useful methods of achieving this that I thought I would share.
Firstly, you will find none of the “lets make homework cool” type stuff here. The Internet has become a much more stimulating place for maths, visualisation and generative images. This is in part driven by the death of those “java applets” as wonderful HTML5 based interactive maths content takes glorious hold. Trying to keep pace with […]
So your here because you just couldn’t resit the title… or you used some very odd search terms in Google. In any case, welcome to the article that gave me the most pause to write about so far. Background. !t was the 1960s (this decade is developing a bit of a reputation) and doctors were treating […]
Because you always wondered what was inside. See if you can guess which IC it was? Useful image for teachers, overhead slides etc. NB: This is not always a good DIY or classroom activity. Be aware that some electrical components create a seriously hazardous dust when broken open. Rectifiers, Hi Power transistors, Older IC’s & IC’s with certain […]