Bent vs. Straight

[LatakiaLover]

This link has been lifted straight from another thread on this forum, but it is so good---so informative---that I think it deserves the stand-alone treatment.

New guys---and Creative Shape makers especially---need to read this.

In an alternate reality where pipe smoking was revered, and there was a Pipe Making World Academy on a mountain top in Switzerland or somewhere, this article would be required reading the first week, guaranteed:

https://www.howellhandmade.com/post/the-bends

[Sasquatch]

One of my absolute best smoking pipes is a Castello that I think they drilled the airway on twice, and missed it both times, and then they went and found it from the bowl. It's a fucking mess. And it smokes sublimely, top 3. And that really pisses my off because I believe in all this stuff, I believe in constant-volume airways and turbulence and laminarity and fucking Bernoulli... all of it. And then you get a pipe that just chucks all that crap out the window, it's kinda frustrating.

But yes, there are challenges in bent pipes, and we all choose our own stopping points, places where we look at the build and say "Well, I'm not thrilled with that." I just think so many cheats and slick tricks are available, and Jack mentions a few there, that it's perfectly within the sphere of "ordinary" to make a very, very bent pipe and have absolutely everything about it, from the airway dimensions to the connection with the bowl be ... basically perfectly normal. I've posted this pic a few places, talking about just one aspect of Oom Paul geometry - the mortise proportion:

Done with a "normal" mortise, say 5/16" by 3/4" deep?




And done with a shorter fatter mortise (a bit luridly so in the diagram):



Suddenly the airway geometry is... basically no problem.

So I mean, I make pipes like this all the time, and it's not to say that I'm smarter than Jack, it's that we have different stopping points in our current geographies, and there's nothing wrong with that - I talked to Brad Pohlman at Chicago a few years back and he basically won't make a pipe (or wouldn't then, perhaps he's modified his view) that isn't a dead straight drilling. Because perfect. And even my straight pipes don't usually feature dead straight drilling - I wander upwards even in the lowly billiard.

I think the idea should be something like building perfect pipes with no compromises. But I think the reality is that every pipe is a a compromise of some kind, somehow somewhere, and mostly, done with care, it doesn't matter a bit. But good wood, make the thing carefully, it'll be great.

[LatakiaLover]

Yes and no.

Being a repair guy lets me see things that no one else does in terms of problems, maintainability, and etc. on a regular basis.

The business of turbulence, airway size, and so forth is definitely a percentage game. I've seen .110" airway pipes that smoke wonderfully well; and normal airways that absolutely---literally---were unsmokeable until being opened to Rick Newcombe size. I'm sure because the pipes in question are my own.

In repair work, the rule is whatever works, works, and don't mess with it unless it doesn't work. Then, moving as far as physically possible in the direction of the ideals described by Jack is the solution.

Pipe makers who are in charge of how things are laid out at the start, though, will definitely make life easier for themselves by not tempting fate in the first place. Wonky designs sometimes work, but sound designs always do.

[Sasquatch]

Sure, another way to word your bolded section might be to say that Jack has laid out conditions of sufficiency for an excellent pipe - build it like so and it will be excellent. What I'm saying is I can agree with those sufficiency conditions, but because they aren't "necessity" conditions, I can find a pipe that smokes excellent and fails to meet those conditions (so they are not "necessary"). You point out Newcombe's specs, George - there's a great example of another, slightly different set of sufficiency conditions - Newcombe's pipes are built using more of a venturi principle, a very large airway tapering down to a slightly restricted aperture. This works like hell, and it's slightly different (if I have it right) than the "constant volume airway" that many North American carvers strive for. Hit these principles in your build, and the pipe will be great. And I think most of us who are seekers of that perfect smoking experience agree on what those principles look like, with only the most minor variances.

This is angels-on-pinhead stuff at some point - it's reasonably easy to build a pipe that smokes really well, you just have to get the smoke pretty smoothly from one end to the other. (I have 5 Castellos with totally different builds - different airway sizes, different funneling on the tenon, different amounts of plenum space... they resemble each other physically in no way, really. And they all smoke.... like Castellos.) The fact that there are so many pipes out there which utterly fail at this is the baffling thing for me.

Jack is going to get off the boat somewhere before the Oom Paul I posted. He has every right to do so if he thinks that it might lead to a pipe smoking less well than he wants - I'm not a fan of churchwardens for the same reason. Meanwhile, I am happy to build Oom Pauls very carefully indeed, and the people who buy them find that they smoke just like straight billiards in terms of moisture. Most factory Oom Pauls are total pieces of shit. Owning one that is not is a delight. Luckily for all of us, not all pipes have to be identical inside or out, and customers can choose to buy from makers like Abe Herbaugh if they want the finest most delicate stem in all the land, from Cooke or Rubio if they want a sandblast they can fall into, or from Jack, or Ryan or Scottie, or Wayne or Tyler or... or hell even from me if they are really not fussy. That's what's so great - the pipe world accommodates all kinds of shades, from 3" tall super stacks to tiny little Kiseru pipes, and people with crooked teeth, people with no teeth... jesus even people who like corncobs.

[DocAitch]

Even if we don’t agree on every aspect of Jack’s thinking, it is a pleasure to follow his analyses, and George’s and Sas’ input are also a pleasure to read.
DocAitch

[wdteipen]

tldr

Just kidding. Bookmarking Jack's blog post for later.

[wdteipen]

Here's some fun bent pipe acrobats:




One of my favorite things in pipemaking is pushing the boundaries of how bent a pipe can be and still not only be functional but also function well. Overall, I agree with Jack's blog. He notes some traditional, well-known methods of compromise when drilling and making bent pipes. Those techniques can be taken to an even further extreme than the "most bent" limit pipe he made and used as an example. On the first pipe above, my goal was to see if I could make a pipe design with the shank passing the full bent point of the Oom Paul. On the second, my goal was to surpass the idea that an extreme bent pipe must have either a fat or a shortened shank. Both of these pipes were done using straight drilling. Two standards that I won't compromise on is that the airway must line up center in my mortise and that it must pass a pipe cleaner from bit to bowl which both of these pipes accomplish.

[LatakiaLover]

Unless the airway is curved (which is a huge PITA to maintain), it looks like you either gave the chamber the undercut treatment, or plugged a hole in the the shank...?

Enquiring minds want to know.

[wdteipen]

The blue line is pretty close. I used a more rounded chamber bit profile which allowed me to drop the airway a bit further from the top of the shank. I chose not to ramp or notch the airway at the mortise because it was so far away.

[Sasquatch]

That's one of the cheats a guy has available - changing the chamber angle.

Changing the chamber shape is also a possibility, either through drilling it at successive angles or hand-tooling. Tobacco is for the most part, pretty stupid stuff, and unaware of the exact shape of its container.