Help: Why does my DCMX-42 rotary table cause air bubbles when mixing epoxy with 3% ultrafine marble dust?

I've been using a DCMX-42 rotary mixer for months on a 12‑hour epoxy batch (Araldite LY 556). Adding 3% ultrafine marble dust (TAN‑101 grade) suddenly started trapping micro‑bubbles, and the cure ends up lumpy.

What equipment or workflow tweaks do you swear by to keep a stone‑filled epoxy smooth?

• Have you tried the JBC 3000 torque‑controlled stir head instead?
• Any tips on degassing the mix with a Vac‑Pump 2000 at 15 psi vs 30 psi?
• Does switching to a silicone‑based mold release (Silanol‑RX) help avoid the bubbles compared to conventional petroleum releases?

Also, I'd love a direct comparison: Talalay silicone versus high‑strength polyurethane for fine‑detail casts in this setup. Most people claim Talalay is superior, but I hear it's just a marketing ploy. Drop your real‑world data, tool recommendations, or even the one thing you wish manufacturers would fix.

Looking for a solid, reproducible method, not just “spray harder”.