Forge Burner Patterns and Build

I use my 3D printer for many things, one of which lately is to produce patterns for making aluminum castings.
Recently I needed a better burner for my LP forge oven and was not satisfied with any that I could find for sale.
The burner that came with the oven had many flaws, not the least of which was a strong tendency to back fire up the mixing tube.
No amount of adjustments seemed to be able to stop it.
And because it was welded together there was no reasonable way to change or improve upon it.

The files I have attached here are for two different sizes of air horn flares and bows that I designed.
My design was based upon the natural gas burners in our home heating furnace.
I felt that it was perhaps an improvement over the common "Frosty" burner designs you see everywhere (NOT that they are bad or anything..!).
The larger set was intended for 1" steel EMT pipe (with the galvanizing removed) and the smaller is for 3/4" black iron threaded pipe.
Do **NOT** use galvanized pipe or fittin