Blast Off!

Started to design the chimney stack, petticoat and blast nozzle.  Used formulas to determine sizing, positioning, etc.  Proved one thing, theory doesn't always work.  If I used the formulas, the 1:3 and 1:6 cones would not be in the right position so I threw out the formulas and repositioned things so the 1:3 and 1:6 cones were in the right spot.  I figured that was more important to get proper draft.  Here's a drawing with the final setup.  The GREEN cone is the 1:3 and the RED Cone is the 1:6  Also included a drawing of the parts that made up the blast nozzle.

Here's the CAD drawing of the blast nozzle.

In order to make things easy to change, I designed this thing so I can adjust the height by adding or removing plates.  The nozzle itself can be easily replaced in case I needed to adjust the blast angle, orifice size, etc. during test runs.  I also drilled 4  small holes at a 3 degree inclined angle for the blower.