Thank you for responding. The pipe nipple is 1/4 inch by 4 inches long.
during the threading process the bottom-most blades of the die broke off.(The die i have is a cutting die not a chasing die)
The reason I'm threading this nipple is to screw it down through that top part so i can not only use as a way to get the propane into the venturi, but also as a form of oxygen control.
i was originally going to use an extended hydraulic bulkhead fitting but the only ones long enough were from the EU. I have all the other parts this is one thing that has given me the most trouble.
What my biggest question is, should i still try the pipe nipple, or is there a better way?
Thank you.