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:
Nice work Paul.
I have not made a bone tenon from scratch, but I have turned some old pipe threaded bone tenons into replacements for Peterson Chimney’s/tenon extensions.
Thanks John. If you ever run out of threaded bone tenons you can use soup bones as an inexpensive backup. 😉
Very nice work. Your lathe looks also home made.
Unfortunately even on “newer” Pete´s the thread doesn’t fit in some cases.
Thanks Martin. The lathe is a fairly standard TAIG.
Ah Yes the gurgeling.Seems to be that on roughly machined extensions it gurgle more.
So I have a very good result chamfering all my not so good alu extensions myself.
I think the gurgel appears when the moisture drop is not big enough to falling down and stays on the rim of the aluminium.
I’ve always wondered how the extension was made from bone. Thank you!
You state that they quit making bone tenon extensions around 1960. I have a deluxe 20s that I picked up at a yard sale a few years ago. It is hallmarked 1978. The extension on it certainly wasn’t metal so I just assumed it was bone. It looked like bone. The chap who cleaned up the pipe for me replaced the old extension with a new metal one that had the three vent holes. It’s a good smoker.
Hi Lowell. Excellent observation–one for the next book! Whenever I discuss dates with K&P, keep in mind I’m using three resources: 1) documented pipes wherever possible (and that’s precious few considering how many have been made); anecdotal testimony from retired K&P craftsmen (who have ranged in age from 65 to 90); K&P ephemera. So when I say they bone tenons disappeared about 1963, it’s because that’s what Paddy Larrigan told me (who worked in the factory from what, 1946 to 1991?), what’s been documented both here on the blog and by myself and Gary Malmberg, and what can be seen… Read more »
interesting work Paul. I wonder if domestic an animal’s bone density is less than a wild one. I recall a moose hunting trip where I got a moose shin bone to give to my Labrador Retriever . He worked and worked it but barely wore it down even after a week. It occurred to me that he might wreck his teeth on it and I took it away. Obviously, moose bone is much more difficult to come by that a domestic beef bone but I think, it you could get something like that it would take the thread cutting part… Read more »
Thanks Marlowe and that is an interesting point – I’m sure you are right that other types of bone will be more or less dense and will keep my eye out for different types to try.
Fascinating as always, thanks Paul, thanks Mark!
Thanks Nevaditude.
Great post. Superb work Paul. How much time and effort was required to fabricate that tenon extension? Marlowe’s question has me wondering about the quality of bone between domestic cow bone and something like that Moose bone. I’d assume the density/strength of said bone would be commensurate with the weight of the animal.
Has me primed to read those past posts regarding tenon extensions. I’ve not given them much thought…
Thanks Robert. Now that I have done a couple of these and have the steps figured out I can make one in about two hours. Yes, I agree, density of various types of bone is an interesting variable and worth some more experimentation.
A Great in depth article on the repair of the Peterson Pipe Thank You for Sharing your Knowledge
Hi Paul! I’m sorry I didn’t get a chance to visit with you at the CPCC show, as I had originally planned to do. Sometimes life gets in the way of things we would rather be doing versus things we need to do. But the next show, definitely! I really enjoyed the read on your foray into the manufacture of a bone tenon extension. Outstanding work, and remarkably “original” looking outcome! I had a bit of a grin when I read your note about the “smell” being akin to what one would experience at the dentist. I know that smell.… Read more »
Hi Gary – nice to hear from you! Yes, I was sorry to miss you at the Chicago show but Mark kindly conveyed your apologies – I hope life has settled down for you a bit. When we finally do connect I want to pick your brain about a design idea for a tapered reamer – I am on a quest to match the Peterson factory graduated bore on a house pipe stem replica.
As far as curing the raw bone before working, that is a good thought – more research needed!
Ah, the tapered reamer quest! I’d love to compare notes and ideas with you on that subject! I’ll be seeing Mark in a few days and see about getting a discussion group set up. I’ve got some ideas on this as well. The trick on this specific reamer for a house pipe stem will be the length needed!
What a great piece! As to proud owner of one of your bone extensions on a house house pipe with a long stem that came from Peterson sans an extension, I can attest to the smoking improvements from the tenon extension. You have given me some great tips about cleaning and maintaining stems with bone tenons. That might make a nice follow up to your post. As we discussed, I keep running across stems in the estate market that seem to have odd threads. Some, as you’ve suggested are probably the result of wear or attempted repairs. However, I have… Read more »
Thanks Ken, glad that extension is working for you in your house pipe!
The biggest thing I have found on the bone extensions is that they expand when smoked, no doubt due to the porous bone absorbing moisture, and then they get stuck in the stem. A good preventive is to unscrew it about 1/8 turn before smoking. If it still does get stuck, don’t try to force it loose, just let it dry out a couple of days and it will come loose again by itself.
Hi Ken! It is quite the conundrum one can have trying to match the old and odd thread profiles. I have experienced this dilemma quite a few times in the past. In fact there have been some cases that I’ve just bypassed the frustration of all of this by removing the threads and going with a slip / friction fit for the tenon extension. In fact, I did a tenon extension recently on Mark’s 1990 Patent Commemorative that utilized a slip / friction fit. The one thing that you do gain by doing this is the capability to enlarge the… Read more »
Jaufré Cantolys, thank you for the fun music and videos! You are quite talented. The second link goes to the same YouTube video as the first one, but this link works for Pipe et Pipe. 🙂
Thanks, Paul. I corrected the link and added Jaufre’s English translation.
Fabulous, thanks Mark!
Looked like skilled hands and good tools.
Good stuff Paul! It was a pleasure meeting you and speaking with you regarding your tennons at the CPG meeting in Chicago. Taking that discussion one step further, I was thinking that using resin stabilized bone or antler could be the answer to the machinability and that material is readily available from knife maker supply sources.
Hello Paul B, Interesting thought on the use of resin stabilizing materials (essentially in the epoxy family of adhesives) So, are you thinking that this would be best done with the use of a vacuum pot? – However, I’m wondering about the possibility of impairing the taste of the tobacco due to the resin material? Granted, the amount of resin needed to stabilize the small bone tenon blank would be very minimal, I’d still be wondering about it. I Still wish we had a greater insight from the past at the Peterson factory on the type of bone used, along… Read more »
Thanks Paul it was nice meeting you in Chicago as well! ? Thanks for the suggestion, I had no idea such a material was available. I will check with some suppliers – stay tuned.