Made some molds out of aluminum as a proof of concept. Moving to steel to reduce warping and make cleaning easier

Original brick size: 6 x 2.5 x 1

Used 8 x 3 x 0.25 slats for top/bottom

Used 8 x 1.25 x 0.125: for main sides

Successfully cast several good bricks

Drilled vent holes in top two corners

Rested at angle under 20 lb lead pot

Fill hole sized experimentally after original hole seized up too easily