Shank extensions

For discussion of the drilling and shaping of the stummel.
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BigCasino
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Shank extensions

Post by BigCasino »

I made a pipe with an acrylic shank extension that I cut a tenon on one end and placed it inside the mortise and of course the extension had a mortise drilled into the other end to receive the stem , I then epoxied the extension into the shank.

Is this the proper way to do this? and if not what is? is it the same for using wood and acrylics?

Also I am curious about how one would cap of the end of the shank for more extreme bends for the shank, do you epoxy material to the face of the briar at the shank end, then drill your airway and mortise? or is this done like an extension ?

Thanks in advance!
caskwith
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Re: Shank extensions

Post by caskwith »

Personally I have found it better to cut the tenon on the briar and slip a ring of shank extension over it, that means the torque of removing the stem is place on the briar with the extension for support. Doing it your way can lead to the extension failing.
LatakiaLover
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Re: Shank extensions

Post by LatakiaLover »

caskwith wrote:Personally I have found it better to cut the tenon on the briar and slip a ring of shank extension over it, that means the torque of removing the stem is place on the briar with the extension for support. Doing it your way can lead to the extension failing.
I agree with Chris.

Some more things to consider when Extension Lust is upon you:

Shank extension problems appearing after a pipe has been smoked for a while are distressingly common. There are many reasons for it---bad construction technique, bad design, using an incorrect adhesive, and using problem-prone materials are the usual ones.

Avoiding problems yourself isn't difficult. The main thing to keep in mind is that dissimilar materials expand and contract at different rates and by differing amounts when subjected to fluctuations in temperature and humidity, and then allow for those things in your design and when choosing materials. That means 1) Using a design that physically blocks/prevents moisture, acids, and tars from contacting the epoxy in the first place; and 2) using a (microscopically) flexible type of epoxy that's designed for harsh conditions and adherence to open-pore materials like antler, bone, wood, etc..

A stainless steel sleeve that blocks access to the extension/shank joint from the airway is the simplest and most bullet-proof way to keep things dry, and the best epoxy I know of for the Shank Extension Mission is one called G-Flex 655.

http://www.jamestowndistributors.com/us ... o?pid=8694
UFOs must be real. There's no other explanation for cats.
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BigCasino
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Re: Shank extensions

Post by BigCasino »

Thanks Guys, do you see a problem using Delrin as a tenon for the shank the same way you do for a stem? so that the extension and the shank would both have a mortise with a delrin tenon junction holding them together?
wdteipen
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Re: Shank extensions

Post by wdteipen »

I've seen some of the experienced makers say that Delrin on Delrin is bad because it sticks to itself. A vulcanite or acrylic tenon with a Delrin mortise works great. I've done it before and it actually makes for a very nice, smooth fit.
Wayne Teipen
Teipen Handmade Briar Pipes
http://www.teipenpipes.com
LatakiaLover
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Re: Shank extensions

Post by LatakiaLover »

Yeah, Mother Nature often doesn't like bearing surfaces to be made of the same material. Many types of metal are prone to a type of adhesive wear called "galling" when used as machine components that touch each other, for example.

In the PipeWorld, having a shank extension and a stem of the same material is generally a bad idea for similar reasons. Problems with sticking, accelerated wear, inconsistent tightness/looseness and so forth will appear early in the pipe's life, and get worse quickly.
UFOs must be real. There's no other explanation for cats.
the rev
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Re: Shank extensions

Post by the rev »

caskwith wrote:Personally I have found it better to cut the tenon on the briar and slip a ring of shank extension over it, that means the torque of removing the stem is place on the briar with the extension for support. Doing it your way can lead to the extension failing.
but if you are doing a really big bend and your airway hole has to be outside of the tenon hole, do you just go ahead and drill it where it needs to go after you have made a tenon on the briar and then use the shank extension to over it?

rev
"but rev, isn't smoking a sin?"

well I suppose if one were to smoke to excess it would be a sin

"but what would be smoking to excess?"

Why smoking two pipes at once of course
caskwith
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Re: Shank extensions

Post by caskwith »

the rev wrote:
caskwith wrote:Personally I have found it better to cut the tenon on the briar and slip a ring of shank extension over it, that means the torque of removing the stem is place on the briar with the extension for support. Doing it your way can lead to the extension failing.
but if you are doing a really big bend and your airway hole has to be outside of the tenon hole, do you just go ahead and drill it where it needs to go after you have made a tenon on the briar and then use the shank extension to over it?

rev
I drill the airway and chamber first then come back to the shank on bents. If the bend isn't too extreme then I just turn the tenon and slip the extension/band over it, if its really extreme or is going to cause a problem in the mortise then I make a 4mm briar plug, glue this into the end to blank off the airway for a set distance then drill the mortise etc.
the rev
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Re: Shank extensions

Post by the rev »

sorry mate, I didn't understand that. Any chance you could draw a picture?

rev
"but rev, isn't smoking a sin?"

well I suppose if one were to smoke to excess it would be a sin

"but what would be smoking to excess?"

Why smoking two pipes at once of course
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