When I was at the age of 21 I wanted to start building aircraft at my own design buy couldn’t find a cheap and effective way to do it. So I decided to build a 4 axis CNC machine that cuts foam from different types like EPS (expanded polystyrene), EPP (Expanded Polypropylene), Depron foam etc..
I didn’t have any financial resources since I was in the Army on compulsory service in that time so I had to improvise. So I scratched and sourced parts form the rubbish and places you can’t imagine: I took the motors apart form old HP printers, the plastic holder of the motors are from an old vacuum cleaner, the drawer slides I took apart from an old server rack, the metal airframe is made from iron profiles(the used for constructions) and the power supply is made of chained laptop power supplies (~60V 5A), the motor to thread adapter is made of the gasline
hose of my beloved Ford Fiesta 88′ (RIP) and on and on.. you get the idea 🙂 the important thing that at the end it worked! I used it cut many profiles and created a lot of never seen before air-frames for RC models. unfortunately the original build thread that describes all the stages of the building was deleted (thanks Microsoft MSN :\) but I have pictures and a video of it doing the first cut.
In order to control the motors that cuts the foam I’ve made the PCB by myself using etching by ferric chloride in my home kitchen, wrote most code to Microchip micro-processor(part of it I took from anothe CNC project) and interface it to an existing CNC software. I was very satisfying look at the motors rotating the first time I ran it. It felt like magic. Back then unfortunately there was no Arduino or something simpler to develop on. Just straight forward old embedded micro-processors.
Here are some picture from the build log and a short clip of the first run/cutting.. I used my microwave as a shelf 🙂 it was back in June 2007!
It was so successful that I decided to use it in the Israel RC Aero Club, I was an instructor that time there and my students used it to build RC models that were cut using my machine. Later on we flow the models together.
Using this machine I scratch build a unique VERY durable flying wing that I called it FPV AXE, (check out the build log at http://www.efly.co.il/forums/showthread.php?t=5597) I used a a special technique that involves foam and composite materials (Kevlar) – Its a combination that create an impressive result of an RC model that flow over 200km/h:
My unique CNC was the first 4 axis foam CNC machine in Israel few month after I published the build log I helped students from the Department of Aerospace Engineering in Technion(Israel) to build one for the faculty use.