General discussion > Gunmaking tools and techniques- metal shaping

Making a Bucks County 2 pc entry pipe

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flehto:
Seems to be some interest in building BC LRs and many of the original BC  LRs have the elongated finial on the entry pipe. Here's some pics and explanations  of how I make mine. Previously made them in one piece but found the 2 piece easier to make and which are joined w/ hi temp silver solder. I now use soldering paste and have found the low temp solder to be sufficient....either can be used.  Both pieces are made from .040 brass sheet that has been annealed by heating to a dull red and either dousing in water or just left to cool which I prefer.

The pipe itself is formed around a 3/8 dia steel rod using the vise jaws but a radiused groove results in the ID when the tabs are formed. I have 1/16 dia hi temp silver solder and lay 2 lengths  on the groove which has been coated w/ borax flux.  A small parallel clamp squeezes the 2 tabs together.  A 1300 degree temp {red color} is req'd to melt the silver solder. When cool, most of the solder is filed off and then a 3/8dia reamer is  run through. Because the ID is now round, the tab can be only  1/2" long {don't like such a long slot in the web}.

The outline of the finial is drawn on paper which has been glued to  what will become the inside ...notice the 2 square cutouts in the paper....this is to align the centerline of  the paper and the centerline on the brass sheet.  The finial outline is now cut w/in 1/16" of the layout.
 
A piece of maple is shaped to simulate the lower forestock and will be used to form the finial....it doesn't have to be the full length.

The sheet w/ the layout is centered on the female form and the forend shaped block is also centered and is then  struck w/ a heavy mallet. The final outline of the finial can now be filed.

The end of the finial that accepts the pipe will have to be formed w/ a round tipped punch so the brass conforms  to the  radiused shape of the form . A drill the dia of the OD of the pipe is clamped as shown and the radiused shape is peened around the drill shank which yields a  perfect fit around  the pipe. As the peening progresses, that area should be annealed a couple of times to prevent cracking.

The 2 pieces can now be soldered. I stick a 3/8 dia steel  rod into the pipe to align the pieces and the rod also acts as a heat sink so the solder in the pipe doesn't melt. A setup for soldering is made and the solder is melted and the BC entry pipe is ready for the filed in grooves and polishing. ...Any questions are welcome....Fred

flehto:
Too many pics in the preceding post, so here's 2 inletted BC entry pipes. The "wings" are spread open and the pipe and finial are inletted to final depth and then the wings are bent in as the inletting proceeds. I use 2 small screws to hold the wings in and one pin for the pipe.

The forms aren't difficult to make and the one shown was lengthened by adding a block.

The pipe length for the entry pipe is 1-5/8" ...there's 1/8" overlap for soldering. The other 2 pipes are 1-1/2". The final length is 4" long and the assembled length is 5-1/2".

The drill used to simulate the OD of the pipe is .455...whatever drill that is. ....Fred

rich pierce:
Fred, I understand most of it but the part about your process necessitating a short tab on the barrel of the entry thimble has me stymied. Do you see any issues with using a conventional entry thimble body with the folded tab which runs near full length of the barrel of the entry thimble?  Is your approach necessary or preference?  Is it based on any original?

Next, how much “lift” do you give the skirt?  I bet aligning it while soldering takes a bit of care. I’d like to see your clamping setup.

Thanks for the tutorial. Very helpful. 

flehto:
Hi Rich.....The 1/2" long tab on the pipe is personal preference. The silver soldering of the "groove" could be avoided by forming and peening  a sharp corner on  the tab, using a steel block so when the pipe is formed around the rod, no radius  groove is also formed. I prefer soldering.  The dim from the top of the finial to the top of the pipe is .040 {sheet thickness}.

The setup for soldering  the 2 pieces is simply 2 blocks w/ a gap between for torch access. The finial end fits tightly around the pipe dia. The 3/8 dia rod is used to align the pipe w/ the centerline on the finial and is then pulled back so it doesn't protrude. It then becomes a heat sink. The assy is soldered upside down w/ a .040  shim under the pipe  w/ the tab centered. To hold the finial in place, small  blocks are on both sides of the finial.

I imagine there might be a simpler way to make this entry pipe, but that's how I do it. Probably stems from the fact that I was a tool and diemaker. Yes....some of the procedure requires  using judgement and the eyes....nothing new when building MLers.....Thanks for the questions.....Fred

rich pierce:
Then there’s the inletting!  That’s the scary part for me.

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