Bowl Coating Experiment

[d.huber]

Totally worth watching: http://www.youtube.com/watch?feature=pl ... cDMaHT1khI

Thanks to Todd Johnson for executing this experiment. I think this leaves little doubt that using a bowl coating of sodium silicate, pumice, and activated charcoal adds a dramatic degree of protection against burn out on a pipe.

One thing I would mention: the temperature at the tip of a candle flame can vary from about 1100 deg Fahrenheit to about 1400 deg Fahrenheit. Those are the kinds of consistent temperatures these pieces of briar were exposed to during this experiment.

Unless I'm mistaken, tobacco combusts around 550 deg Fahrenheit which is, at most, half of the temperature these pieces of briar were exposed to. Now I've seen inexperienced pipers puff on a pipe until that thing was scalding hot, which could certainly lead to temperatures like those we see in the experiment. Generally speaking, I imagine that anyone willing to shell out enough money for an expensive briar is likely to be more cautious with their pipe while smoking and handling that pipe. However, Todd provided an image over on smokersforums.co.uk that illustrates that there are folks out there who treat their high grades like absolute crap. I've included that photo at the end of this post.

I think this experiment proves beyond a reasonable doubt that by leaving a chamber uncoated you are taking a degree of risk. For me, the benefits of an uncoated chamber outweigh the risk of having a pipe burn out due to an issue with the briar or an overzealous smoker.

However, I am not Todd Johnson and may very well eat my words given my choice to leave my chambers uncoated. If I do, you'll hear it here first.

Beat up Bo Nordh

[e Markle]

Thanks Todd!

While conditions are certainly different in a tobacco chamber, I'm not sure we could reach a more definitive conclusion. As I always say, the question to coat or not is purely preference, but it obviously will help with burnout.

[mredmond]

That's definitely enlightening. It proves the value of a bowl coating, at least in one regard. Preference still applies, of course, and those who think water glass will kill them will still think water glass will kill them. I've yet to have a bad experience with a bowl coating other than one I made incorrectly, and I have some high grade pipes with water glass coatings. I have had some naked briar pipes that were/are more troublesome. I know some folks like the taste of singed briar...I'm still on the fence.

[Alan L]

Cool experiment!

I once stuck a thermocouple in the bowl of my large shop pipe (7/8" diameter chamber, 1.5 inches deep) just to see what kind of temperatures were happening in the bowl. In the center of the bowl while half-smoked, it idled at around 450 degrees F, but puffing like a steam engine brought that up to 750 degrees F, by which time it was a noticeably hot and uncomfortable smoke. The temperature on the edges of the chamber was much lower at all times, rarely exceeding 400 degrees even under duress.

I suspect the most heat a bowl sees, as reflected in the burnouts I have both seen and experienced personally, is when a pocket of tightly compressed tobacco turns into a little hot coal on one side of the bowl. Improper packing is the culprit there, but soft spots and cracks in the briar do make that much worse. Rim char like on that poor Nordh is the result of bad lighting practice, probably from using a torch-type cigar lighter.

The other poor technique that ends in burnout is when someone is determined to smoke the last little bit of the bowl, trying hard to light that bit of damp dottle right at the draft hole. It's easy to make a serious 1100 degree hot spot doing that...I can see where a sodium silicate coating would prevent or at least help with all but rim char.

Hmmm... I have some bubble alumina refractory coating intended for use in forges and furnaces that is rated to 4000 degrees F. Wonder if it tastes bad...

[Joe Hinkle Pipes]

That was a pretty conclusive demo. I may attempt to coat A few bowls and see if that is something that I want to incorporate. I prefer the professional, finished look of a bowl coating. you know I have read a lot of reviews of various tobaccos and A phrase that pops up a lot is "burns down to a fine white ash". I have never been able to smoke the dottle at the bottom of the bowl down to a fine white ash. I have however received a mouth full of ash and hot embers and bitter smoke that makes me feel like spitting. Can anyone out there produce this "fine white ash" that so many speak of?

[d.huber]

That was a pretty conclusive demo. I may attempt to coat A few bowls and see if that is something that I want to incorporate. I prefer the professional, finished look of a bowl coating. you know I have read a lot of reviews of various tobaccos and A phrase that pops up a lot is "burns down to a fine white ash". I have never been able to smoke the dottle at the bottom of the bowl down to a fine white ash. I have however received a mouth full of ash and hot embers and bitter smoke that makes me feel like spitting. Can anyone out there produce this "fine white ash" that so many speak of?

In almost 7 years of pipe smoking, I think I've "smoked down to a fine white ash" maybe twice. I usually have a few pieces of dottle at the bottom of the bowl and that's fine with me.

[Ocelot55]

That was a pretty conclusive demo. I may attempt to coat A few bowls and see if that is something that I want to incorporate. I prefer the professional, finished look of a bowl coating. you know I have read a lot of reviews of various tobaccos and A phrase that pops up a lot is "burns down to a fine white ash". I have never been able to smoke the dottle at the bottom of the bowl down to a fine white ash. I have however received a mouth full of ash and hot embers and bitter smoke that makes me feel like spitting. Can anyone out there produce this "fine white ash" that so many speak of?

In almost 7 years of pipe smoking, I think I've "smoked down to a fine white ash" maybe twice. I usually have a few pieces of dottle at the bottom of the bowl and that's fine with me.

I don't know what you guys are talking about. I always have nothing but a fine grey ash at the bottom when I'm done smoking. Oh, and most of my bowls are uncoated. (joking)

[e Markle]

Can anyone out there produce this "fine white ash" that so many speak of?

Once you get down to the last 1/4 bowl, take an acetylene torch and...

[d.huber]

Can anyone out there produce this "fine white ash" that so many speak of?

Once you get down to the last 1/4 bowl, take an acetylene torch and...

rapidly dispose of the pipe?

[Alan L]

This was covered once before. There is a most eloquent post near the bottom by Nick. Look for it...viewtopic.php?f=3&t=2798&start=0

[d.huber]

This was covered once before. There is a most eloquent post near the bottom by Nick. Look for it...viewtopic.php?f=3&t=2798&start=0

[Joe Hinkle Pipes]

Alan your memory is amazing!

[wdteipen]

Occasionally, I will have a bowl that smokes down to fine ash. It's usually with a ribbon cut. I wouldn't say the overall smoking experience was better or worse than one where I have a little dottle left.

[Joe Hinkle Pipes]

Ribbon cut always seems to behave better for me as well. Burns more even and with less maintainance. Maybe that's why I'm partial to 965 and squadron leader.

[Alan L]

Alan your memory is amazing!

What can I say, that was a quote that tends to stick vividly in the brain, is it not?

[WCannoy]

This was covered once before. There is a most eloquent post near the bottom by Nick. Look for it...viewtopic.php?f=3&t=2798&start=0

OMG! The more I read, the less I was able to breathe! This one had me in tears laughing!

[andrew]

Can anyone out there produce this "fine white ash" that so many speak of?

Once you get down to the last 1/4 bowl, take an acetylene torch and...[/quot
Geez. That was going to be my helpful contribution, now I'm left with nothing... *sigh*

Well, at least all of you know how to get the flame down there without charring the rim now .

You could save yourself some time and just fire a couple round of the caliber of your choice straight down the chamber. Same result. Wear eye protection in either case. Safety first.

[Sasquatch]

Firm logs of shit aside, I generally have horrible ugly lumpy dottle, and that's because I smoke the sticks-n-stones "whole leaf" blends from Mac Baren, namely their roll-cakes (Club and Dark Twist mostly).

I will say this though: I recently got a new Castello, uncoated, and I smoked a bowl of Carter hall in it, and then smoked a bowl of Mixture Flake in it. I was sandblasting at the time, not "working" the pipe at all. And... I fucking burned it, man. I wasn't smoking hot at all.... I spiderwebbed that thing, and I knew it from the taste - unmistakeable briar taste. It's really easy to burn briar, or at least some pieces of briar. It really got me thinking about coating, as much as I dislike the coatings I've dealt with (Stanwell, Peterson, Ser Jacopo), it may be a necessary evil.

[andrew]

That sucks about the pipe. Hopefully you didn't take too many years off its life.

[e Markle]

Firm logs of shit aside, I generally have horrible ugly lumpy dottle, and that's because I smoke the sticks-n-stones "whole leaf" blends from Mac Baren, namely their roll-cakes (Club and Dark Twist mostly).

I will say this though: I recently got a new Castello, uncoated, and I smoked a bowl of Carter hall in it, and then smoked a bowl of Mixture Flake in it. I was sandblasting at the time, not "working" the pipe at all. And... I fucking burned it, man. I wasn't smoking hot at all.... I spiderwebbed that thing, and I knew it from the taste - unmistakeable briar taste. It's really easy to burn briar, or at least some pieces of briar. It really got me thinking about coating, as much as I dislike the coatings I've dealt with (Stanwell, Peterson, Ser Jacopo), it may be a necessary evil.

I did that once on a pipe I had reamed too aggressively. I tasted like I was sucking on a log from the campfire. Not good. I charred the briar just above the draft hole.