It's possible this may be too technical (AKA "boring") to write on, but what the hell... I thought I would make a quick post on the process behind the creation of the new Ligne Bretagne Duke & Don shapes. I've been wanting to do something like this for some time now, as a wholly alternate shape style for the Ligne Bretagnes. When you're working with partially pre-fraized stummels, your final design options are perforce limited, but I find it an entertaining challenge to see just how much variety and individual personality I can inject into the line, considering that they are in essence machine-made pipes.
If I were making this as a Talbert Briar, it would in many ways be simpler. I'd cut a length of stem rod, hand-turn the tenon to the desired size, file the stem to shape, drill and hand-turn a custom band to the desired style, and drill and turn/shape the bowl to what I wanted. All of this would add up to $400+ of shop labor hours.
Ligne Bretagnes, of course, sell for $140-$190 on average, so none of the above is possible. I need methods to do everything above for roughly 1/4 the amount of shop labor time, given that Ligne Bretagnes also need to be priced where they can be sold direct OR wholesaled to retailers.
The first order of business are the bands. To get high quality AND time efficiency, these are factory-machined parts that come exactly sized and pre-polished - Each one is identical so my shank size turning can be pre-set. (In reality, I use three different sizes of bands, and three different styles, to accommodate the different shank sizes of various bowl shapes, but this is the thing about individual small-shop craftsmanship - Nothing is ever *quite* identical).
Below you can see some of the ingredients of the Ligne Bretagne Duke/Don stew:
A few bands always come scratched or otherwise imperfect, so I set these aside and use them for "masking" - Pop them onto the turned shanks to protect them during sandblasting and overall bowl shaping, then swap them later with the final, finished bands. The turning of the shank should be tight enough to hold the bands on by pressure alone, but I always add some commercial-grade epoxy just for extra insurance over time, since the wood swells and shrinks with temperature and humidity.
Another key part of the process is to greatly speed up the tenon sizing and fitting. On most Ligne Bretagnes, I use Delrin tenons - I prefer them for their strength and smooth fit. Here, however, this isn't possible. The thin stems simply don't have enough body to insert a Delrin tenon into, even if it were easily possible to drill them out without splitting them. Instead, they'll need to be turned. This simply can't be done by hand for a $147 pipe, so instead I set aside the time to assemble and customize a commercial tenon turner. Here's what one looks like:
The turner is mounted on the headstock of one of my metal lathes. The various slots allow cutting blades to be ground and inserted for a variety of fraizing purposes, but here we're just focusing on making a reliably-sized tenon. I mounted the cutting assembly onto the head, then cut a piece of guide pin that matched the airhole sizes of our stems. I also drilled and cut a thicker bracing tube to mount it into the center of the cutting head, and both keep the guide pin from flexing for better turning accuracy, as well as providing a handy stop point for each tenon so they would be a consistent length.
Once this was assembled, a lot of "test and size" experimenting took place - The adjustment knob above is slowly dialed to slide the cutting blade in and out towards the guide pin, until it's at the exact point where it will cut a tenon that matches the size of your drilled mortises. The sliding tool mount is then locked in place. The small carbide cutting blade at the tip will automatically shave down a stem tenon as the stem is pressed onto it, while leaving a slight bevel at the base of the tenon to add rigidity and help protect a bit against snapping. Here it is in use:
The cutting head is spun on the lathe and the stem is pushed onto the guide pin. The blade cuts a perfectly-sized tenon every time. It takes a lot of time in the set-up process to customize it to provide accurate results each usage, but once that work is done, turning a tenon is as simple as pushing the stem onto the guide pin. In this way, I can reliably make dozens of pipes efficiently and with reliably quality fit and finish from pipe to pipe, and make them all on a budget that a lot more people can afford! Et voila, the new Ligne Bretagne Dukes and Dons, a whole new look for the brand to help kick off 2015:
(Note - This does NOT mean that all Ligne Bretagnes will look like this from now on - I'll continue to make the classic standard shapes as well. But it is something new and different and fun to add to the brand, and that's always a good thing)
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