Someone recently said that “bowl coatings” were such a hot topic of debate that to not even go there. But here I am, again inexorably drawn back to the topic by teeming contradictions of misunderstand. Now, IMO, you can damn well coat your bowl with whatever you want, so long as it works for you (even if it doesn't), no harm no foul as you will be the one living with the results. I even recently experimented with coating a bowl with what was essentially "cactus nectar." (a sugar) It worked great.
But it seems to me that the reason for all the dissent (or whatever it is), is a lack of facts. Presented with some facts, in the light of that, what is there left to argue but personal preference, and why should personal taste ever be a matter of disagreement? Life is ABOUT personal choices! But some things are just a matter of fact or fiction. A few simple facts:
On another recent thread it was argued that carbon was both a much better conductor of heat than briar and also was much more porous, and that this was hard science. Well, I'm a scientist, and that statement makes no sense, as the properties of carbon vary widely with the state it is in. Statements were made about graphite, one of three basic common states of carbon in order to support the argument about bowl coatings, but graphite is a crystalline carbon (granular or clumpy in nature). Your lead pencil is graphite pressed into a rod with a binder to help hold its shape.
Depending on its state, carbon as graphite is one of the softest materials known; in another state as diamond, it is the hardest naturally occurring substance. Depending on the state, both the electrical and thermal properties vary widely, so making a blanket statement about the efficacy of carbon being a better thermal conductor than wood is a vacuous one unless you define the point and conditions.
But let us look at it a better way: take graphite powder then take some sawdust--- both powders. Which will burn first and fastest? Which would you want covering your hand to protect you from a torch? Carbon has a higher oxidization/melting point than tungsten. The conductivity of moist wood was quoted, but again, water is a very good insulator! Look at your swimming pool--- it takes forever for the water to heat up, then long after dark it is still warm. You cannot consider the thermal properties of moist wood in such an argument as you are changing the conditions of the materials.
The space shuttle Challenger--- it burned up years ago for lack of a few insulating tiles broken off during the launch. What were those tiles? Carbon! When you smoke your tobacco or cremate a body, what is left behind--- the ash, fundamentally carbon and trace minerals. When stars die in their old age, with millions of degrees in their core, what do they produce? Briar? No, Carbon. There is even a "carbon star." So when you treat your bowls with a coating of some kind to condition the bowl, you are essentially putting there some form of carbon or mineral because it is more resistant to the heat than the briar itself, be it a silica, ash, or some organic mixture that will carbonize.
What brought me to writing this? Time and again I read strongly put forth and defended arguments here that are simply pure bunk, often due to misunderstandings in the two parties each speaking of different things. Reading a link now on another thread about How to clean a pipe--- I thought what the hell and started reading it; here is one excerpt:
---Placing one finger or the palm of your hand over the top of the bowl, shake the pipe for a few seconds to evenly distribute the ash along the inside walls of the bowl, which will greatly speed the formation of "cake," a protective layer of carbonized tobacco and ash inside your pipe. Cake acts as an insulator, greatly extending the life of your pipe and guarding against burn outs.---
YES! Now, this is not news the method above, but it very well makes the point that the reason for cake is to /protect/ the pipe. If the carbon layer conducted heat more readily than the briar itself, it could not do that! But it is not really a matter of thermal conductivity here, but rather, one of thermal /stability./ And therein lies the oft-stated misunderstanding. The reason why cake works is because the carbon (or silica) is STABLE at a higher heat than the briar--- given a level of heat, briar is still an organic compound that will undergo chemical and structural changes. Carbon or silica will not. The point of the cake is not so much to /insulate/ the heat, otherwise, your bowl would feel no warmth, the point of the cake is to endure the contact with the hot flame of the burning tobacco because it will do so repeatedly without breakdown, whereas the briar would not, and this is what extends the life of the pipe.
So, perhaps a better way of thinking of cake and bowl coating is not as an “insulator” as much as a “wear surface.”
But it seems to me that the reason for all the dissent (or whatever it is), is a lack of facts. Presented with some facts, in the light of that, what is there left to argue but personal preference, and why should personal taste ever be a matter of disagreement? Life is ABOUT personal choices! But some things are just a matter of fact or fiction. A few simple facts:
On another recent thread it was argued that carbon was both a much better conductor of heat than briar and also was much more porous, and that this was hard science. Well, I'm a scientist, and that statement makes no sense, as the properties of carbon vary widely with the state it is in. Statements were made about graphite, one of three basic common states of carbon in order to support the argument about bowl coatings, but graphite is a crystalline carbon (granular or clumpy in nature). Your lead pencil is graphite pressed into a rod with a binder to help hold its shape.
Depending on its state, carbon as graphite is one of the softest materials known; in another state as diamond, it is the hardest naturally occurring substance. Depending on the state, both the electrical and thermal properties vary widely, so making a blanket statement about the efficacy of carbon being a better thermal conductor than wood is a vacuous one unless you define the point and conditions.
But let us look at it a better way: take graphite powder then take some sawdust--- both powders. Which will burn first and fastest? Which would you want covering your hand to protect you from a torch? Carbon has a higher oxidization/melting point than tungsten. The conductivity of moist wood was quoted, but again, water is a very good insulator! Look at your swimming pool--- it takes forever for the water to heat up, then long after dark it is still warm. You cannot consider the thermal properties of moist wood in such an argument as you are changing the conditions of the materials.
The space shuttle Challenger--- it burned up years ago for lack of a few insulating tiles broken off during the launch. What were those tiles? Carbon! When you smoke your tobacco or cremate a body, what is left behind--- the ash, fundamentally carbon and trace minerals. When stars die in their old age, with millions of degrees in their core, what do they produce? Briar? No, Carbon. There is even a "carbon star." So when you treat your bowls with a coating of some kind to condition the bowl, you are essentially putting there some form of carbon or mineral because it is more resistant to the heat than the briar itself, be it a silica, ash, or some organic mixture that will carbonize.
What brought me to writing this? Time and again I read strongly put forth and defended arguments here that are simply pure bunk, often due to misunderstandings in the two parties each speaking of different things. Reading a link now on another thread about How to clean a pipe--- I thought what the hell and started reading it; here is one excerpt:
---Placing one finger or the palm of your hand over the top of the bowl, shake the pipe for a few seconds to evenly distribute the ash along the inside walls of the bowl, which will greatly speed the formation of "cake," a protective layer of carbonized tobacco and ash inside your pipe. Cake acts as an insulator, greatly extending the life of your pipe and guarding against burn outs.---
YES! Now, this is not news the method above, but it very well makes the point that the reason for cake is to /protect/ the pipe. If the carbon layer conducted heat more readily than the briar itself, it could not do that! But it is not really a matter of thermal conductivity here, but rather, one of thermal /stability./ And therein lies the oft-stated misunderstanding. The reason why cake works is because the carbon (or silica) is STABLE at a higher heat than the briar--- given a level of heat, briar is still an organic compound that will undergo chemical and structural changes. Carbon or silica will not. The point of the cake is not so much to /insulate/ the heat, otherwise, your bowl would feel no warmth, the point of the cake is to endure the contact with the hot flame of the burning tobacco because it will do so repeatedly without breakdown, whereas the briar would not, and this is what extends the life of the pipe.
So, perhaps a better way of thinking of cake and bowl coating is not as an “insulator” as much as a “wear surface.”
