Little Machine Shop has a solid column conversion kit for the X2 mini mills that drastically improves rigidity, as well as a 2” riser block. Also really nice folks to deal with, very knowledgeable and helpful.
Solid Column Conversion Kit | Mini Mill Conversion Kit
This mini mill conversion kit is designed to convert a HiTorque Tilting Column Mini Mill to solid column. This kit includes the base and column along with fasteners and instructions. Order online today.littlemachineshop.com
I like LMS, I just can't handle their shipping rates.