I had great succsess with" Smooth On cristal clear" that i cast into a groove in the wooden core ,
no problems with bubles and very strong bond' I attached two photos of boards in the making ,
Did you have to vacuum and heat cure the cristal clear?
I used a 300 series product and chose to live with the "tiny bubbles", creating the "champagne of rails," after my testing showed it was strong enough despite the bubbles. Bubbles may even improve flex, which might be desirable in some builds....
Just curious about others' experiences...
I use Polycraft SG2000. I find I get less (almost zero) bubbles with the fast cure stuff (2min pot life) than I do with the slow cure (8mins) but as you can imagine 2mins is not a lot of time to do anything. I'm intrigued by downunder's pre-cast rails but have yet to see any advantage (for myself) yet. No vac or heat cure required...just a big ass mess where I havn't established a decent way of pouring the rails yet.
"For Best Results . . . Best results are obtained using a pressure casting technique.
After pouring the mixed compound, the entire casting assembly (mold, dam
structure, etc.) is placed in a pressure chamber and subjected to 60 PSI (4.2 kg/
cm2) air pressure for the full cure time of the material.
Post Cure - Castings will reach “full cure” faster and achieve maximum physical
properties if post cured. Allow material to cure for recommended cure time at
room temperature followed by 4 - 6 hours at 150°F/65°C. Allow casting to
come to room temperature before handling."
I've done lots of experimenting. A lot is described here, even some destructive PU testing :