The Pencil Shank Pipe Hazard (for purchasers)

[georged]

The pencil shank design has taken off in popularity the past few years. They are elegant, fun, and make a statement.

Simply reducing wood thickness around a chamber and airway from stem to stern is NOT all there is to it, however.

Unfortunately, many carvers wanting to jump on the bandwagon THINK that's all there is to it.

Unless the shank is reinforced with something like a stainless steel tube, and the design of the shank/bowl attachment area and heel of the bowl dealt with properly, the pipes won't stay in one piece for long. Especially if sandblasted or rusticated (the gooves, valleys, and low spots create stress risers, which significantly increase fragility).

I'm creating a thread about the situation because I keep getting sent stuff like this:







I some cases, repair isn't even possible.

Also, how long the chamber will last if the shank does survive is a good question. In the above example, the wood thickness at the heel is .072" / 1.82mm. Less than one third the industry standard minimum. It will burn through if smoked all the way down repeatedly, guaranteed.

Anyway, that's it. Forewarned is forearmed, and all that.

 

[AppalachianPipe92]

Man I'm sorry to see that. That's a beautiful pipe.

 

[Doctor Chopper]

The pencil shank design has taken off in popularity the past few years. They are elegant, fun, and make a statement.

Simply reducing wood thickness around a chamber and airway from stem to stern is NOT all there is to it, however.

Unfortunately, many carvers wanting to jump on the bandwagon THINK that's all there is to it.

Unless the shank is reinforced with something like a stainless steel tube, and the design of the shank/bowl attachment area and heel of the bowl dealt with properly, the pipes won't stay in one piece for long. Especially if sandblasted or rusticated (the gooves, valleys, and low spots create stress risers, which significantly increase fragility).

I'm creating a thread about the situation because I keep getting sent stuff like this:


View attachment 219840
View attachment 219841
View attachment 219842


I some cases, repair isn't even possible.

Also, how long the chamber will last if the shank does survive is a good question. In the above example, the wood thickness at the heel is .072" / 1.82mm. Less than one third the industry standard minimum. It will burn through if smoked all the way down repeatedly, guaranteed.

Anyway, that's it. Forewarned is forearmed, and all that.


View attachment 219847

Good advice. Make sure it is reinforced with steel. Also make sure you want it to smoke like a steel pipe and not a prolonged contact with briar.

 

[kcghost]

Solid advice. No steel tube then don't purchase the pipe. I the says "it's fine it will hold" they are severely delusional.

 

[Puffaluffaguss]

I never been into the pencil shank, always kinda figured they were way too fragile. But with a metal pipe type thing I could see it being very permanent and durable.

 

[brian64]

Altinay makes pencil shank meers with a carbon fiber shank insert.

 

[georged]

... But with a metal pipe type thing I could see it being very permanent and durable.

It is not automatic, though.

If a standard mortise is simply shunk to match, for example, then it becomes the weak link in the chain. (The only way to avoid that is a proportionally correct in placement and length external band, or change things up altogether with a reverse tenon design.)

Also, meerly using a steel tube does nothing for the strength of the connection between the bowl and the shank. It also must be propotionally correct in design, or the bowl will snap off with surprisingly little pressure.

 

[Jbyrd]

Was always a worry of mine that I would break them so never tried.

 

[georged]

Altinay makes pencil shank meers with a carbon fiber shank insert.

Carbon fiber has an amazing strength-to-weight ratio, but the outer surface of the material does not withstand abrasion well at all.

And when the coating wears through, the micro-fine fuzzy stuff under it "blooms".

I've dealt with it a number of times in the course of repair work. Based on that, if I was a pipe maker I would not use it.

 

[brian64]

Carbon fiber has an amazing strength-to-weight ratio, but the outer surface of the material does not withstand abrasion well at all.

And when the coating wears through, the micro-fine fuzzy stuff under it "blooms".

I've dealt with it a number of times in the course of repair work. Based on that, if I was a pipe maker I would not use it.

Very interesting...glad to have learned that before I ended up purchasing one.

Somehow blooming micro-fine fuzzy stuff inside the airway doesn't sound so good.

 

[bluegrassbrian]

For a second I thought that was one of my old Beckers.

 

[georged]

For a second I thought that was one of my old Beckers.

Could be. It was bought as an estate and is an Italiano Becker.

 

[Doctor Chopper]

Carbon fiber has an amazing strength-to-weight ratio, but the outer surface of the material does not withstand abrasion well at all.

And when the coating wears through, the micro-fine fuzzy stuff under it "blooms".

I've dealt with it a number of times in the course of repair work. Based on that, if I was a pipe maker I would not use it.

The carbon fiber is covered by briar on the outside, and likely gets a cake coating on the inside. Would that mitigate the fuzz?

 

[georged]

The carbon fiber is covered by briar on the outside, and likely gets a cake coating on the inside. Would that mitigate the fuzz?

Pipecleaner wire. The sharply cut, and often slightly hooked end of a pipecleaner would slice through the glaze of a carbon fiber tube quickly. How fast would depend on a smoker's "cleaner use rate", of course, but could happen during the first smoke.

Good quality stainless steel, on the other hand, wouldn't even even notice. That stuff is TOUGH. (try cutting it by hand sometime, as opposed to a tungsten carbide power tool)

 

[georged]

As long as this thread got started, I might as well keep you updated on the attempted repair.

Why do I sound uncertain about the outcome? Because it depends on how straight the airway is. If the shank warped from smoking (most do), reaming it to accept a length of SS tubing might not be possible. Friction/contact drag being the problem. If the torque required to overcome it is higher than the structural strength of the shank at any point (including where it's attached to the bowl), she go snappy snappy.

The epoxy for the initial join takes 24 hours to cure in any event, so the answer won't be known until tomorrow.

 

[renfield]

Great info and feedback, Georged. Much appreciated.

Your comments on carbon fiber are especially good. Every material has its uses and places it probably shouldn’t be used. Perfect case in point here.

 

[sablebrush52]

This is why I own Scottie Piersel's pencil shanks. Nobody, and I mean NOBODY, knows better how to make a strong pencil shank. Scottie did a lot of research and a lot of testing, climbing up a ladder and hurling pipes high into the air to land on concrete, so she could learn what works and what doesn't.

 

[anotherbob]

reminds me of what an architect told me about Avant Garde buildings. "There is a reason most don't make experimental designs and it is not because they can't". Also known as form following function.
I also never have liked pencil shanks (except on smaller pipes) they always look like they're going to break.

 

[canucklehead]

The carbon fiber is covered by briar on the outside, and likely gets a cake coating on the inside. Would that mitigate the fuzz?

Carbon fiber fines (fibrous dust) are known causes of lung cancers, COPD, and mesothelioma. I used to work with composites (making boat hulls) and carbon fiber is nasty stuff compared to traditional glass fibers (which are definitely not healthy themselves).

 

[hoosierpipeguy]

This shape or design holds little appeal to me. Thankfully.