Casting Emerald Wax Problems

[Archerm]

I have done quite a few pieces with engraving on them and haven't had any issues. this was cast like all my castings with the schedule above. No issues with corners breaking off. I feel that if you are haveing edges breaking off it could be 1 of a few things.
1. Not removing all the uncured resin from the piece.
2.You don't have a full cure.
3. Your investment ratios are not correct.
4. You are not bench sitting your flasks long enough before casting.
5. If using non phosphate investment you are taking the investment to to high of a temperature.
6. Quenching your flasks to soon after casting.
7. Improper spruing.