Thanks Eric. The entry pipe w/ its long finial is sometimes a deterrent in building a BC LR. Below are some pics of how I make them.
Inletting is fairly difficult .....but if you spread the "wings" open and when the "top" of the pipe is to depth, then little by little the "wings" or sides of the pipe are pushed in and inletted until the sides are to depth. I use one pin through the pipe lug and a very small screw for each "wing". This allows the pipe to be removed.
A drill, the same dia as the OD of the pipe is clamped in the form block and the end of the finial is peened and formed to match the pipe. A few anneals are req'd to prevent cracking. The finial and pipe are then hi temp silver soldered together. A snuggly fitting drill is inserted into the pipe bbl and acts as a heat sink while silver soldering the 2 pieces together.
The form will also make a one piece BC entry pipe and after the pipe portion is formed and the lugs are silver soldered together, is clamped in the hole and the "forend" form block is used. A steel punch w/ a radiused tip is used to peen the transition radius and then the rest of the finial is filed to suit . Needless to say, the brass has to be periodically annealed to prevent cracking. I think the 2 piece is easier to make.
When closing the lugs of the pipe , I use hi temp silver solder and lay a 1/16 dia length of silver solder in the radiused groove of the lugs in the ID ....the silver solder fills in the groove and enables a much shorter length of finished lug as shown.
This BC entry pipe no doubt can be made w/ a steel mandrel, but the form blocks shown have done quite a few BC entry pipes. How others do it would be interesting.....Fred