We finally got around to doing some tests.
Resin used is FunToDo standard.
From left to right we have sugar water (about 100g of powdered sugar applied to 2dl of water, might want to give lower concentrations a true in the future), glycerin, table salt water, Epsom salt water, and regular water all the way on the right (just to catch drops from the spoon).
The links below the images are to bigger version. We didn't have the best camera on hand, so the pictures aren't great.
Everything settled:
Pictures directly after stirring:
15 minutes later:
Some impressions:
Sugar water: By far the worst, takes ages to separate and while I'm not sure if the gradient that forms is just pigment or tiny droplets of resin, I wouldn't recommend it. A little more vibration dampening than the water mixtures, a little less than Glycerin.
Glycerin: Initial separation is fairly quick, but you're left with a glycerin-resin boundary that's cloudy/has lots of little resin streaks going into the glycerin that take a long time to settle. Best vibration dampening.
Table salt: works nicely, fast and clear separation, only takes about 5-10 seconds to fully separate. Worst vibration dampening.
Epsom salt: Not sure what to make of this. Separation is fast, slightly faster than Table salt, and you get a really nice layer separation. But the water is left with a faint red color, which might be pigment. I couldn't make out individual resin droplets in it, so I have no clue what it is. Might also be small amounts of resin sticking to small salt crystals and "floating in mid-water". Same vibration dampening as water.
For now, I think I'm sticking with salt water, the difference to epsom salt is marginal at best and table salt is cheaper and easier to get.
We'll let the sample stay still for some weeks to see how they fair longterm.
And in case anyone is interested, the printer so far: . Already got the z-axis working with the arduino, so all that's left to do is adding a shutter, hooking everything up and calibrating. Hopefully we'll get our first prints next weekend.