Here is a video of my third and largest anthill to date (originally filmed June 21, 2014):
I tried to be careful in digging around the ant colony, but apparently I was not careful enough, and some pieces broke off.
Here is a photo of the finished product:
And a closer view:
Below is a demonstration of using a small number of pins to drive a large number of servos using 74HC595 shift registers. The shift registers are serial-in, parallel-out, with latch.
This is pretty low-tech, and I’m sure many people have done similar things before. The demonstration was actually testing two things, one being the overall method (including software design) for manipulating a large number of servos using shift registers, and the other being the fabrication of the circuit board itself.
There are many places online where people describe using toner transfer. The concept is simple. Just use a laser printer to print the circuit, and then use heat to melt the toner off of the paper and onto the copper surface. Etching solution removes copper where the toner is absent, and then the toner is scraped off the copper. Easy.
The tricky part is getting the toner to stick to the copper when melted, and to not stick to the paper. Ordinary paper is extremely poor for this purpose because the toner much prefers to adhere to the paper rather than the circuit board. Special-purpose papers designed specifically for toner transfer are available, but they are rather expensive. Some of the glossy paper intended for inkjet photo printing is said to be good, but I haven’t done enough research to know which is best.
One person had suggested magazine paper, which worked well for me, and has the added advantage of being very inexpensive. I have not directly compared it to glossy photo paper, but it worked about as well as I could have hoped.
I also found that sanding the copper surface with 220 grit sandpaper improves the adhesion. Someone online had recommended 600 grit sandpaper, but it is too smooth, and adhesion is poor. I notice a big improvement with 220 compared to 600.
Some folks also suggest using wax paper and some suggested kitchen parchment. DO NOT USE THESE. For one, it doesn’t work, and in addition it will mess up your printer. In my case the toner did not adhere at all to the paper, and it came out as a powder which fell off the page and made a mess. Regular documents did not print properly until I had fed several sheets through, and even now the printer does not print perfectly.
I may try some photo paper for my next circuit board, but until then, the recipe I have seems to work fairly well: a magazine page and 220 grit sandpaper. Oh, and I use a regular iron. I haven’t optimized the temperature but it seems I don’t need to.
Here’s a short video showing the furnace setup I use for aluminum casting.
One of the things I’ve been experimenting with to reduce cost of a 3D printer system is a system of rails and pulleys, to eliminate the linear bearings and lead screws that are used in the more conventional RepRap designs.
With a table saw, a straight V shaped groove can be cut on the underside of a plank. With a matching rail shape, an extremely simple linear slide can be made, with very good stiffness and no slop. As long as the lateral forces are low, which they usually are with a FDM style printer, this ought to work well for very low cost.
Here is a video of an earlier attempt, using primarily particle board. The grooves and rails were made using a table saw.
(Original video taken August 8, 2014.)
(This setup was later torn down and rebuilt because poor planning had left no way to securely attach a Z-axis above the XY table.)
Here is the first attempt I made at casting an anthill. Inspired by an extremely popular video that probably almost everyone has seen by now.
Here is mine:
The original date of this attempt was June 15, 2014.
Here is the finished product:
A few lessons: first, always wear safety protection.
Second, do not use pipe for a riser, because the pipe ends up essentially welded to the piece and very hard to separate. A berm of sand works much better.
Third, do not attempt to cast abandoned ant colonies. In this case there had been an ant colony but it was no longer active. This causes the casting to be of poorer quality, as there are many cracks and collapsed tubes. I also believe the explosion is partly due to the anthill being abandoned. A small pool of water or an underground earthworm or grub worm may have been the cause of the explosion, and it stands to reason these may be much less likely in an actively maintained ant colony. Of course this does not negate the necessity of safety protection.
A later video will describe the set up I use for the furnace and crucible.
I’ve just set up a family of accounts, using this domain, and also a new gmail and youtube account, for showing the stuff that I do. Generally this will be related to robotics, 3d-printing, electronics, and metal casting. Clearly there is overlap in many of these areas, so this is not meant as a categorization, but an overall guide to the topics I’ll be posting about.
Mathematics, software, philosophy, politics, and astronomy are also fascinating to me, but are going to be outside the scope of this website.
To start with, nothing will be categorized, but if the volume is high enough to warrant categorization, then I may subdivide the posts later.