Tenon Material - Wood?

[Literaryworkshop]

I'm working on getting my stems fit flush, and I want to try out the "floating tenon" method. (That's what I'd call it if I were talking about casework, anyway.) I'm nowhere near ready to make my own stems, so I'm stuck with the pre-formed ones for now. From what I understand, I should knock off the pre-formed tenon on the stem, face the mating surface flat with a Forsner bit, and then drill the stem to receive the new tenon, the other end of which will be inserted into the wooden part.

I've got a couple drilled blocks sitting on my workbench right now, and I'd rather not wait for an order of delrin rod to arrive. Any reason I couldn't use a wooden tenon instead of a delrin one? I'm pretty sure I have some poplar scraps lying around, and maybe some other species as well. I won't be hard to drill everything straight on the drill press.

Thoughts?

[The Smoking Yeti]

I tried to walk down this same path early on. My advice? Buy the Delrin. It will save you tons of heartache, and let's be honest- a wooden tenon wont hold up to the test of time. It'll just raise your blood pressure.

http://www.onlinemetals.com/merchant.cf ... op_cat=181

[dogcatcher]

Where are you at on the Gulf Coast? Most larger towns have an industrial supply house that carries Delrin. Some real large machine shops will also have it.

[caskwith]

Get the delrin, it will be worth the wait.

[wdteipen]

Delrin doesn't expand with moisture or shrink when dry. Get the Delrin. A wooden tenon is a bad idea for a pipe.

[Literaryworkshop]

Okay, that makes sense. Sort of.

Briar is wood, too, so someplace in the pipe you still have wood mated to non-wood. Why doesn't briar have the same problem as a wooden tenon would have? Shouldn't the briar expand and contract around whatever non-wood stem/tenon material you use, delrin or otherwise? Or is briar very stable relative to other kinds of wood? Obviously, briar isn't listed in any of my go-to books that list wood properties and characteristics, so I'm really shooting in the dark here.

I should say I'm not afraid of the work involved in making my own tenons, wood or otherwise. I've done a good bit of joinery by hand, including mortise-and-tenon work. I can drill and fit accurately without much trouble. But I understand that the constant swings in temperature can play havoc with the dimensions of any piece of wood, and a tenon would be highly susceptible to that. Yet there are pipes that have wooden stems. How are those stems usually attached?

I really am trying to understand the logic behind all this.

I'm near Mobile, by the way. Lots of industrial supply places around here. I may just take a look.

[dogcatcher]

I am no pipemaker, so take this for what I think it's worth, 2 cents. Delrin is an extremely hard rubber so it gives a little. On the other hand wood moves, as humidity changes so does the wood, so the tenon hole size will change. So I think that is the reason Delrin is used as the tenon.

[Sasquatch]

Here's some technical info on briar:

http://www.rmperkins.com/RMPerkins/Misc ... fBriar.pdf


In short, yes, briar is very dimensionally stable after the boil/dry process. Where a chunk of pine will move 1/8" per foot in 6% humidity change, a piece of briar probably wouldn't move at all.

So yes, there's a wood to non-wood sliding joint, and it works fine with rubber or delrin, less good but acceptable with lucite/acrylic, but the big answer here is that the wood is briar.


And yes, lots of pipes "feature" maple, ash, oak etc stems and joints, and mostly they are, and hopefully I don't lapse into pipemaker jargon too badly, pieces of crap.