Form Kastolite using Styrofoam?

I ended up pulling the top piece and plinth form off at 15 hours after mixing at 70 F / 21 C.
Construction wedges and composite de-molding wedges against the plywood and a heat gun to unbind the hot glue between the plywood and white plastic outer chimney tube.
a-The plinth had a small dry/unflowed corner at its top/form's bottom
b-the chimney has a small crack that coincides with the split in the outer chimney form
c-the lid portion nearest the CNC spindle has a spot that did not have enough material, about 1/4" (6mm) shy.

** Should I patch that letter 'c' portion of the lid with same material while it is still 'green' or go back with something meant to perform better when thinner? Refractory mortar? **

Thanks!

 

Thanks Kelly.
It is a crack on the top horizontal surface of chimney and then something that follows down where the witness mark should be. Not 100% sure how deep it goes from the top.

Inner form is a heavy carboard tube recycled from work and waxed before pouring. In retrospect I should have split or weakened this for easier de-molding. I was so excited it was the correct OD I did not think about that. The outer white tube form is plastic but had to be slit to make its ID the correct chimney OD. Had I not had the slit and hot melt glue joint I'd been in bigger trouble removing it

 

De-molded at 23 hours.

The plastic and Styrofoam, both with a layer of #2 paste wax, released from the refractory. I did manage to pull out a few beads from the foam. The foam was not machined with draft.
The plywood with paste wax did not release as well but did not remain stuck to the molded part.
The cardboard tube with paste wax is stuck and the cardboard is damp. Looks like I will have to work it out.

There are a couple non-flowed areas on the surface that were deep/down in the mold. Perhaps I need to look into some sort of vibrating table or rig it to be air-chiseled on the bottom side?

So, when I get into using the concrete forming tubes, is it time for the clear packing tape as a release medium?

 

Thanks Kelly, I really appreciate the advice.
Letting the cardboard burn out would be easier that what I was trying yesterday
I will look into the turbines and a spring table. We use springs in a similar fashion at work so perhaps I can 'beg and borrow' some different ones to try.

 

Thanks Kelly. I told my guy at work and he's already laying out springs and saying 'how about something like this?'

Veni, vidi, (drilly, wedgey), vici...

Drilling a ring of 3/8" spaced (9mm) by 1/8" (3.2mm) diameter holes into the 'growth rings' of the solid cardboard tube allowed it to be split, wedged, and removed with so much less effort that was exerted yesterday. Adding the screws to the holes gives a little more 'split'. I need to grind the chimney opening a bit more on the lid before I can get a shot of the pieces in place.