just built this up today made from 2 x 6" fire
extinguishers and 4" x 2mm wall stainless steel vortex pipe and 120mm x 120mm x 3mm wall ss box section
using t2h and ppottys builds, combining them both to give short run ( 4 1/2" ) to vortex tube but also plenty to stack inside and save on the filling times ( burn box 9" length x 9" ) height may need adjusting
total length 15" x 7 5/8" burn box 9"
burn box width is 7 5/8" x 9" high and 9" long at the moment
as you can see im well on with it just got other things to do to finish off then up for testing of it
however im wondering if 9" is going to give me same problem like before im hoping the shorter pipe to vortex may stop the back flow