Drills Sizes, Request Tutorial

[mso489]

In a recent post, one of our resident carvers or estate renovation crafts people were running down

the different size drill heads used in drilling pipes. I know nothing about the sizes, and the difference

in sizes, nor which of my pipes are drilled to which size. I do know, on one occasion, I had to trade back

a beautiful curved Dublin pipe (A Chacom, I believe) because I just could keep the drill hole clear of pipe

cleaner lint, a problem I haven't ever had before or since, over several decades (plus). Can people give

a brief primer on drill sizes? Is there an easy way to measure these? Is it a consideration in shopping for

most pipes? I'm not interested in increasing the drill size on any of my pipes. I just want to know more

about this specification on pipes in general. And, why is this never mentioned in pipe specs?

 

[pstlpkr]

I'm going to begin by breaking one of posting's cardinal rules, by stating that.... I don't know anything about the sizes used to drill pipes. :D
I do know; however, that some pipe smokers enjoy an open draw and others a more restricted draw.

Some; a wider bowl and other not so much.

Also; some like deeper bowls, and some others ... not so much. :wink:
So; I'm sure, that when some of our makers chime in, they will all offer up a variety of recommendations.

It'll be fun to read their responses.
So, that being said.... this was a long winded bump, for a great question. ::

 

[ejames]

By "drill hole" do you mean the airway through the shank? If so I've seen them run anywhere from less than .125" (1/8") up to .171" (11/64"),average is about .156" (5/32" or 4MM) which is what most artisan pipemakers use I believe.

Factory made full bent pipes often will not pass a pipe cleaner,not because the airway is small but because of the angles involved.

 

[mso489]

Definitely I'm asking about the airway through the shank. Does the shank airway remain that same width ( 5/32") right through the stem

in most cases, or does this narrow to some degree in some pipes? Second question, would it be useful to take along a 5/32" drill bit

and run it into the shank to see if it is more, less or the same as average, when buying a pipe? I've been smoking pipes on and off for

about 40 years, so I am somewhat tilting at windmills here, but it is a basic functional part of the pipe that people don't usually discuss,

so I thought it was worth bringing up. Thank you for the information so far, and any other "instruction" is appreciated. If I end up

ignoring this in buying pipes, at least I know something about it.

 

[ejames]

A lot of factory made pipes will not have the same size airway in the stem as the shank. Most artisan pipes will up to the funnel,which widens out to make up for the reduced height. Factory stems can be drilled bigger,but that can be risky!!

 

[zack24]

Over the past few months, I've tried a few variations on draft holes in the shank and drilling of the stem to get a really open draw using Harris as a guinea pig. Just switched to a 4mm for the shank. The stem is drilled with a 4mm tapered drill that stops 1" before the button. The last 1" is drilled to 5/64 and fanned out to a v shape. Then it's polished internally to smooth out the transitions and rough edges....That is a very open draw...You'll never be able to measure all these elements in a pipe you're buying- best method is to stick it tween your lips, suck in and if it whistles, it ain't open....

 

[mso489]

Ah, the whistle test is about low tech enough for me to master. Maybe I could draw the air through my

fingers folded around the stem, so the pipe shop guy doesn't feel I'm de-sanitizing his pipe. A lot of

art goes into shaping the airway; it's more than just a drilled hole. I knew that, but this illustrates it

in more detail. Thanks!

 

[peckinpahhombre]

I once read that JT Cooke uses a 3.6mm draft hole, and that his draft holes are that width all the way through the length of the stem until just before the lip, at which point it fans out wider. I certainly like the way his pipes smoke, but to be honest it is all a bit of a mystery to me.

 

[cigrmaster]

All of my artisan pipes are drilled at either 4mm or close to it except my one Mike Butera, I think Zack measured that one to about 4.3 or so. He also measured my Castello which is famous for their open draws and I think that one was 4.5mm. For my tastes an open draw is extremely important and I can tell immediately if a pipe is not drilled large enough. If you read Rick Newcombs in Search of Pipe Dreams, he is a proponent for a measurement of 4.3-4.7 for shank dimensions and claims he will have his most expensive pipes from the likes of Bang and Jess Chonowitsch re drilled to his specs. I find my Castello which is the most open a great smoking pipe and I do have to pack it tighter than my others, but it is no big deal. I think everyone should try a pipe with a nice open draw because of how it smokes. Pipes like these will allow you to put a pipe down for a couple of minutes and go back to it and it will still be ready to puff on. I find the flavors of my blends to taste better in pipes with an open draw and they are a genuine pleasure to smoke.
peck, now that I know Cooke only drills to 3.6, plus he only uses acrylic for his stems makes him not worthy of a spot in my collection. I am amazed you would put up with those defects, if you want send me a couple and I will have Zack drill them properly and I can smoke them to make sure they are worthy of you. I would like a couple that are in thee 50 gram range. You have my address.

 

[dennisfbird]

And I thought talking about drill sizes would be boring.... my mistake...

 

[smokeybear]

As far as the draft hole along the stem and to the shank i dont know if this would help to answer your question but it is also and interesting find. This weekend if you noticed my thread i did some work on a small Cutty. This work involved expanding the draft hole in the stem. Now i know thats not the shank but this pipes like 3" long so it might as well be. Anyway i expanded it one size at a time and finish at a 5/32" every time i did i i blew through to clear the burr and the draw was more open each time. I now see however that being this is a small pipe bowl wise a wide open draw may not have been a wise choice, yes its easier to pass a pipe cleaner now but as i smoke im taking in the smoke too fast, this risks the bowl to over heat faster.
What im trying to get at is maybe there is a better choice of diameter in a draft hole maybe MSO489 is on to something.
Maybe there is a bowl size to drill diameter ratio here that were not seeing.

 

[cigrmaster]

smokey, all you have to do is pack your bowl tighter and the pipe should smoke just fine. The bowl size should have nothing to do with the size of the shank, I don't believe. I had a small group 3 Dublin and it was wide open and it smoked just fine.

 

[zack24]

Smokey, The 5/32 in the stem is drilled with a tapered bit. The 5/32 in the shank is drilled with a straight bit. You can drill almost any size you choose, because what is ultimately going to determine the flow is the last 1" of stem where most guys are using a 1/16 or a 5/64 bit that is then fanned out to a V shape. It basically gives you a slow speed column of smoke that accelerates in speed as the diameter decreases near the button. If you had the same tiny diameter through entire length, you would build in resistance through the entire length and have a tight draw. Same basic idea of how a pneumatic cylinder works...(This coming from a guy who never made a hand-made stem before May......but I think the idea makes sense...)
...and Harris- that's the other part- you can adjust your resistance on the front end by packing, have the stem and shank wide open, and smaller at the bit...my epiphany I just had is that it is a lot like cooking on my Big Green Egg Smoker- I leave the air intake grate wide open, pack the charcoal with a hole in the center, and ultimately control the speed of the burn with a restriction on the top of the chimney...

 

[tbradsim1]

Zack, think of it like putting your thumb over a open hose, you decrease the pressure but increase the velocity, making it draw better.

 

[salewis]

Rick Newcome in his book 'In Search of Pipe Dreams' devotes and entire chapter to the importance of drilling a pipe to increase the draw. Also, he has a drawing of a pipe with his recommended and specified modifications. This book is a must read for pipe smokers and even if you do not agree with his dictum of the greatest pipes are the Norwegian pipes it is still a must read, especially for new pipe smokers.

 

[smokeybear]

@Zack24 i agree with everything you said. My stem however was drill the same throughout the whole stem and its just a hole no v shaped taper at the end of it. Its for that reason i was thinking of finding a small tube that i can insert into the 5/32" hole to decrease the draw but to keep my pull consistent. What i am worried about is that it is such a small bowl that if i pull in with a wide open draw the air flow is strong enough to extinguish the tobacco in the bowl. This is why i believe i had to keep relighting.
Your thoughts on this. I know your a very experienced pipe maker so it would be great to here what you think.

 

[zack24]

Smokey Bear- Two things- I think Harris and Bradley mentioned- if your pipe keeps going out, it might need to be packed tighter- creating a restriction by compressing the tobacco on the top end of the process. I don't think the 5/32 hole on the button is a issue- The reason you find the v shaped airway on the last inch of hand cut stems is to let you flatten the thickness behind the button to 4mm or less so it's a comfortable bite and to move the same volume of air through a hole that has to have a small diameter- (if you had a 4mm draft hole and a stem 4mm thickness behind the button, that obviously wouldn't work). If you want to do a quick test to see if a slight restriction on your stem works, the a really low tech way just to test it would be to get a piece of typing paper 1" wide, roll it up into a tube over a 1/16 drill bit, pull out the drill bit and stick the paper tube in the draft hole and then fire it up. If you like the results, buy a 5/32 hardwood dowel about 3/8" long and drill a 5/64 hole through it...and stick that in the draft hole...