Casting and molding
In my experiments i often have to restrict C.elegans worms to a particular circular area of the plate (to confine them to stay on a bacterial lawn) for at least several hours. The way I do it at the moment is by putting a standard stainless steel washer like so:
However after this part of the experiment it is necessary to pick the washer up without disturibng the worms or bacteria on the plate and without scratching the agar. I can use tweezers to do that easily if the walls of the washer are high but in that case delivering worms to the middle of the washer is made complicated by restricted access. Therefore I decided to make a mold of a washer with low walls but with a special tab on the side that will make picking it up easy.
I designed a simple 3D model in Antimony and produced a png height map:
It was necessary to increase the black (height 0) areas around to allow space for 1/8th inch end mill.
Fortunately the whole cut required only a rough cut and i applied the oomoo right away but as a result of confusion i applied only one part of oomoo and the mixture did not solidify. I had to scoop it out:
I mixed the oomoo parts together again and reapllied to the wax:
The first cast was with the Drystone (in the interest of time):
And this is how it performs on the plate:
