Well, everyone knows what syrup is. Sweet thing!
Probably it isn't on your kitchen, wide-spread in cakes.

As you may remember from previous update, I faced with capillary effect problems another time - oil just runs away from epoxy. One approach was to change mold some way or to pour more oil. But you know - more oil isn't good for health of an actuator, so I decided to find a way how to prevent runaway with same mold and same amount of oil.

And I gracefully present you this -> !!!I thought that problem was in viscosity... And it surely was!
I bought a bottle of magnificent corn syrup and water-thinned it (10 syrup per 1 water) to get epoxy-like viscosity. It's dirt cheap and yes, it has pretty high viscosity, without water-thinning it outperforms epoxy drastically.

Main thing: as a syrup it's just a high-concentration solute, so reducing concentration by water-thinning is a reasonable process. And as you may guess - it's possible to dissolve it in water after hardening of epoxy!

How great! Results are incomparable to results with oil, stripes are bending perfection : )
P.S. I love that it doesn't requires any noxious solvent.

Secondary part about electromagnet, as I've one completed:

Of course it still has somewhat illogical design, but as experimental equipment it should work. One thing with which I faced - compromise between voltage and current, to reduce heat dissipation on control circuit's semiconductors.

This electromagnet has a resistance of 2.2 ohms, well... :D
Quite low, but it is required from my perspective to have small powerful coil. As you know - inductance rules and induction heater still being delivered, so that's why I can't make cores with high permeability now, sadly

However I made pretty pictures from oscilloscope and first version of control circuit with that magnet!
You can see current on coil (reminder: it represents energy of magnetic field), and how boundaries of energy oscillations can be changed with magic of this circuit - here I move lower bound, different runs are coloured differently.

And here I move upper bound, different runs coloured as previously.
I think it shows it pretty decent now, thanks for greater inductance of a new electromagnet : )