Having started a discussion on laser cutting on a thread in the 3D Printing, Laser Cutting and CAD group (Thanks to AndyY for adding the laser cutting bit!) I'll continue to post some of what I'm doing here just too.

One of the things that is concerning me is how to make the corners of building. Some people are trying interlaced brickwork and I'll probably try butt joining some ABS as well but one thing I wanted to try was to mitre the corners. I had trying to sand anything accurately so I'm going to try and cut the angle on the laser cutter. To do this I'll need to hold the wall at 45 degrees so needed to make a giant jig. This was also a chance to see just what the cutter could do.

So armed with some 3mm MDF I drew out some pieces which should slot together. The first attempt was a spectacular failure as I failed to follow my own notes on focusing the laser and then used the speed suggested in the machines manual for 3mm ply. This was way too slow (cutting speed 10, laser 100%) leaving a burning trail of destruction in the laser's wake. Moral of the story is to always try some test cuts with your new material before trying for a proper cut. Second attempt couldn't have been better (cutting speed 40, laser 100%), the laser sliced through the MDF and the parts just held together by friction as I lifted the sheet out of the machine.

The resulting pieces just slotted together perfectly with no slop and a formed the shape perfectly. The 45 degree slope has lines engraved at 10mm intervals to aid alignment. The theory is that I can attach a wall to the jig with double sided tape and then cut along the edge to give a 45 degree mitre. Whether it will work remains to be seen but it seems worth a try.

At the weekend I also drew up a little goods office based on some drawings in the GERS journal. I'm going to use this as a 'test card' over the next few months, trying different materials and methods while I learn. This was test one straight off the machine in 3mm MDF. (Cut speed 35, laser 20% for mortar, 100% for cut)