My kids and I have started geocaching. We were in Sweden this weekend, and found 9 caches. Very cool. But we need some gifts to leave, so I’ve made a design and laser cut. See below.
My kids and I are working on an automatic ping-pong ball thrower. We’ve come to the following design, which uses two rollers (paint rolls) being turned by separate motors. The laser-cut frame is supposed to also hold a servo which lifts the ball into the rolls, possibly controlled by sound-driven electronics. We’ll see where it ends up.Â The files for lasercutting your own are here and here. They are licensed under Creative Commons Share Alike.
Laser cut ping pong ball thrower by Lars Kristian Roland is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
I’ve used InkScape to draw them.
No, I can’t use my laser cutter to actually remove the copper on the PCBs. Unfortunately. Well, I haven’t tried as I expect it won’t work. But I can use it to remove the photoresist, instead of using a transparency and UV box. I’m not sure it’s simpler, but I wanted to give it a go anyway. Â Here is a picture of the board after I’ve ‘engraved’ it using the lasercutter.
And here is a picture after it’s been etched, the normal way, using FeCL. The FeCL solution was a bit old, so the quality of the etching is a bit uneven. It shows promise, though I must admit I’m increasingly using professionally produced boards. But for a quick prototype, this is quite simple and fast.
OK, sorry to repeat myself, but I made another iteration of the box design. This one looks better. The top is now glued on, and the side-walls are thin and fit outside the top. Well, it is best described by a picture. The design is on thingiverse.
Here’s another attempt of making a case for the MSP43o Launchpad, with room for the LCD board I’ve made and touch sensors. The black side is 3d-printed, while the top and bottom is laser-cut. In this model I’ve used screws to fasten the top and bottom plate, but it may have been prettier to glue the top plate on. I could have chosen a less transparent plexiglass/acrylic, but I did it this way in the prototype to show the inside. It would probably be nicer with a less transparent one, but I would have had to cut a hole for the LCD display. I wonder if I could maybe cut a square hole for the lcd display and cut a similar square in transparent plexi, and glue it inside the whole. I might try that out.
There is a room in the side for the USB contact.
There is space between the capacitive sensors on the board and the top plate, and it turns out that air is a bad material to ‘conduct capacitive touch’, while silicone apparently is pretty good. So I filled the room with transparent flexible silicone glue from a tube. The type you use on the bathroom to waterproof stuff. I had to turn up the sensitivity in the firmware, from 1000 with nothing there to 50 (so the effect on capacitance is still pretty big). The acrylicÂ is about 1.5 mm thick, so the total is about 3-4 mm of silicone plus 1.5 mm of acrylic.
A youtube video:
So every cool platform needs a laser cut acrylic box (apparently). I’ve now designed one for Launchpad, and here’s a picture.
The design is still a bit work-in-progress, but here are the files anyway. Expect some changes. The screws don’t quite fit for example, but I might change it so that the top is glued on, making the top slighly nicer looking with no screws.
Launchpad Lasercut Box by Lars Roland is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.
Here’s a video of the laser-cutter cutting:
Here’s a paper house I cut on my laser cutter. My kids built a few of them. The plans are here.
Here’s a video of me testing out the solder-stencils made on my new laser cutter. It works pretty well, and is much faster than using a syringe. I’m actually surprised it was not messier and it worked as well as it did. The mylar stencils are overhead stencils for printing on from Farnell.
Here’s a Raspberry Pi case I’ve made using the laser cutter. It’s still a bit rough around the edges, and I’ve got to tune it more to see exactly which power levels I need etc. For this cut, it didn’t cut through the acrylic on all the parts, so I had to break off some of it. Better next time. (The design is from Ladyada, and you can buy a version from there.)
And here’s a picture of the result of trying to make some solder stencils. The picture shows the result of different power settings, with the optimal being circled in black. The optimal seemed to be 10% speed, 20% power with a wet paper below. There are probably many other configurations that would work, like for example lower power and lower speed.
I just ordered a Full Spectrum Laser cutter. I’m excited to see what I can build with it. There’s a special offer these few days and they were kind enough to extend it to me although I hadn’t seen the offer. The customer service seems to be very good. I’ve ordered Acrylic from Inventables.com and will report back with more info when the stuff arrives.