Stephen -  I am not much of a caster -- but have done a lot of fiberglass work on boats.

Resin - catalyst mix dependent on the resin - though it sounds like you are using polyester resin.   Methyl Ethyl Keytone is the usual stuff --

Use less at warmer temperatures, and use less to be less brittle.  You still want enough catalyst to cause the resin to set -- and to thicken in a reasonable time if you are mixing colors together with swirls.   The larger/thicker the pour, the more the heat, the less catalyst needed.

Summary -- a fair bit of art and experience is needed.   Sticky blanks can be heat cured.  Some use a toaster oven on low -- but sun through a window works too. 

By the way --- super super sharp edges are needed, and I like carbide riding the bevel on poly-resin like snake skin blanks.

Are you using the mica powders from Coasta Scent?

Stephen,
I have cast pen blanks & stoppers. The first problem I think your having is not following directions on the amount of catalyst to base liquid. When I mistakenly added even one or two more drops of catalyst the blank was more brittle than usual.

Do you get blowouts when drilling? if so the best is to put a piece pf wood under it & have both held tightly so you get less that way.

Another thing I do is when ready to turn first use some thin CA on the ends around the tube on the acrylic, it will help hold it so you get less that way.

Another is like they said take very light cuts & if you have it Craig's EWT tools.

Let us know how you make out.

I agree with Freddie on tool choice and Chuck on amount of catechist drops I cast bottle stoppers but not pens but  I would think the end result would be the same good luck.
                           Spider

I assume you are using casting resin and know that the more rsein you cast at one time the less catalyst it takes per oz. Also the hotter the resin the less per oz. Ifyou don't have a pressure pot youcan put your resin in a cup surrounded by hotwater which will lower the viscosity of it and allow the bubbles to come out easier and you wont need as much catalyst.I use a paint pot for pressure.
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