347. Peterson Tenon Extensions Made from Bone
by Paul Combs, CPG
There are plenty of great postings and comments on the PPN Blog about Peterson Tenon Extensions – how they work, the difference they make in the smoking qualities of Peterson pipes, whether the cross-drilled vents matter, what material they are made of, and occasionally getting them to fit properly (see Posts #208, 154, 290, 322 ). Tenon extensions are a feature of the higher-grade Peterson system pipes including the Deluxe, Supreme, Premier, and System Star lines. Going back to the Patent days, 1898 being the oldest example I personally have seen and until around 1960 the most recent, the tenon extensions were made of bone. Since then, they have been made of aluminum.
Working with Peterson pipes of varying ages I have seen tenon extensions in these configurations:
• 8.3 mm diameter thread, 0.75 mm pitch, 5 mm bore (made of bone, both with and without cross-vents)
• 8.0 mm diameter thread, 0.75 mm pitch, 5 mm bore (bone)
• 7.0 mm diameter thread, 1.0 mm pitch, 3.5 mm bore (both bone and aluminum)
• 6.3 mm diameter thread, 1.0 mm pitch, 3.5 mm bore (aluminum, with and without cross vents)
• 6.0 mm diameter thread, 1.0 mm pitch, 3.5 mm bore (aluminum).
In recent production, 6.0 mm x 1.0 mm appears to be the Peterson standard. When I requested a replacement tenon extension from Peterson three years ago this is what they sent; unfortunately, it won’t grip in a tenon that is tapped at 7.0 mm or 6.3 mm diameter even though the 1.0 mm thread pitch is the same.
Over the years I have made several tenon extensions myself out of aluminum, a couple out of Delrin, and have long wanted to try my hand at making one out of beef bone. This was in part because I wondered how bone behaved as a material in the shop and secondly because I hoped, if it worked, to be able to make period-authentic tenon extensions for some of my older pipes. I assumed that the bone Peterson used was bovine (beef) because they are hard, a decent size, and readily available.
I asked my wife to set aside some bones for me the next time she made soup, which brings us to the next step in the adventure…
These bones have been thoroughly cooked, so I trust are also sterile. Choose a bone slice with straight grain and a thick wall.
I used a scrap of 3/8” round stock to mark a ‘target’ zone and then marked cutting lines.
Plain old hacksaw for this step…
Chuck it up in the 4-jaw nice and snug, adjusting so that the block is relatively straight horizontally and the target circle is close to centered.
Making it round. This step is a bit noisy at first and smells like soup! Part way through…
One end is now round.
Flip it around and turn the other end. I switched to the self-centering 3-jaw chuck in this step for convenience.
Cut to target diameter for threading and chamfer…
After cutting the threads with a threading die. This part is tricky, and the bone wants to crumble a bit.…
Turn around and mount the threaded end in the 3/8” holder. Now I can use the collet instead of the chuck for the remaining steps…
Comparing against the original tenon extension for dimensions and shape…
Final shaping with the chisel by hand…
Drill out, starting with the center drill and making small cuts, backing the drill bit out out often to clear the debris…
Change over to the 5mm machine drill bit and finish, again backing out often to clear debris.
Replica extension next to the original.
Mounted on my house pipe stem…
Conclusions: Bone is definitely a workable material but has limitations. It smells like soup when you first start machining it, then transitions to something like the smell you get in the dentist’s chair when being prepped for a filling. It has grain similar to wood and the density varies – there are harder spots and softer ones. It is stronger than a soft wood but is on the brittle side and your work piece will split apart if not drilled carefully, slowly, with the drill bit centered, and frequently backing the bit out to clear the cuttings. Bone wants to crumble a bit when cutting threads with a die – again, go slowly. Bone definitely won’t take the kind of abuse aluminum will when being machined and I can see why Peterson switched to aluminum – I suspect they had a lot of spoilage losses when making the extensions out of bone. As for smoking qualities, I can already vouch for bone – in my pipes with bone extensions I do not get the gurgle or moisture collection on the extension that I frequently do on my Petes with the aluminum extensions.
THIS WEEK’S PLAYLIST
Not long ago Jaufré Cantolys emailed me and shared a remarkable music video with me, remarkable because he not only composed it but played the accordion and sang on it, too—and even better, it’s about our love of tobacco! He writes,
I have only one Peterson pipe in my pool of pipes, but I’m sure it’s the best one! Regarding French pipe smokers, the great issue for us is: how to to find good tobaccos? In France it’s forbidden to buy tobacco on the Internet, so we have no choice but buying from tobacco retailers. The problem is that since pipe smokers are very few in France, retailers prefer to sell cigarettes, E-cigarettes or cigars. The few ones who consent to sell pipe tobacco only offer a very limited choice. It’s not so difficult to find Chaco, Davidoff, Also, Burchum Riff, Clan, Caporal, or WO Larsen, but it has become difficult to find Peterson tobacco, and Cornell& Diehl and Samuel Gawith are no longer found. As a consequence, French pipe smokers have become a very united group, ready to help each other and share their discoveries. If a pipe smoker travels to Swiss or Belgium or Germany or any other country where the regulation is more flexible and the choice is wider, he will buy the maximum authorized quantity in order to share with his friends. This solidarity is beautiful: it reminds me of the early Christians under Roman persecution.
Regarding my music, no, I’m not a professional musician. I compose, play and sing only for my friends I’ve sent an English translation of my lyrics, but it’s fairly rough because so many of the words I chose are French slang and old-fashioned words. For example, we have many words to say “pipe” in French (pipe, Bouffard, Bruyère, Bruyère…) – but I know of only one in English! And the same goes for tobacco (Tabak, per lot, petune, gross-out). It was difficult to avoid repetitions. I didn’t try to keep the rhymes and the number of syllables, just translated the meaning.
Tango de jean Nicot (english version)
I play also the guitar. You can find on this link another song of mine (but the lyrics have been written by a friend), imitating the style of the great French singer Georges Brassens:
