Sorry, I shouldn't have put a link to my blog above. Link has been removed and I have pasted the text of the article below:
When buying a pipe, nothing seems to be more appealing than a uniformly straight grained pipe, and these normally come at a premium price. So why are so many briar blocks cut across the grain, and are we storing up future problems?
As a restorer, I have had the opportunity to handle and inspect thousands of pipes. My latest restorations for a client contained two vintage straight grained examples. One was a Fribourg & Treyer Straight Grain and the other was a Comoy Silver Mounted pipe from 1907 again with beautiful straight grain. During restoration, I discovered that the Comoy pipe had a number of bowl cracks running down the inside of the chamber. Of course this pipe has over 100 years of smoking attributed to it, and it had been over-reamed leaving many nicks around the rim. In fact one of the cracks had initiated at a rim nick being a point of weakness. However the Fribourg & Treyer pipe was a more modern example, probably from the 1970's. The pipe had not been over smoked and the walls were quite thick, but there was also a crack developing on the rim of the pipe along one of the grains. This got me thinking if there may be long term issues with straight grain pipes.
Briar root is a natural material and will display many of the characteristics of other woods. When you think about sawing a piece of wood it is much easier to saw across the grain. Trying to saw along the grain is much more difficult as the saw sometimes wants to fall into the natural grain of the wood as opposed to along the proposed cutting line. So is this one reason why so many briar blocks are cross cut? However, if you want to chop a piece of firewood with an axe, you would be chopping like mad to cut across the grain, but cutting into the grain will create a natural split and force the wood apart. Logs are sawed across the grain and split down the grain.
Bending a piece of wood across the grain will have some flexibility before the wood breaks. The same cannot be said of trying to bend along the grain. When timber is used as a support, the weight load is always placed across the grain. It is clear that across the grain is the stronger of the two options.
When you smoke a pipe, the heat in the bowl will cause expansion of the briar. In a cross cut pipe, the walls will retain an element of flexibility as well as having more strength to counter these expansions. But in a straight grain pipe, these expansions are hitting the walls in the weakest possible place. Too much expansion and the grain will start to split causing cracks in the bowl. This is especially true in straight grain sandblasted pipes like the Dunhill Shell pipes, which have weakened the structure of the briar even further by removing some of the material between the grain. If you intend to buy an estate Shell Briar, make sure the walls are not too thin and carefully inspect inside the chamber.
Whilst straight grain pipes may be beautiful to look at, you should be aware of their weaknesses. Here are a few tips to help you preserve the life of your straight grain pipe.
1) If you are planning on buying a straight grain pipe, make sure you buy one which has thick walls. Thin walls provide little protection against the strains produced by the heat while smoking.
2) Don't smoke your pipe hot. The hotter your pipe becomes, the greater the expansion in the walls which could easily crack the bowl. If you are a heavy puffer and hot smoker, perhaps straight grain pipes should be avoided in favour of cross cut briar.
3) Control the cake build up in the pipe. Cake absorbs moisture which turns to steam, expanding even further. Steam is very good at creating forces in the briar - think of steam driven engines! The more that cake builds up, the more steam is created and the greater the forces are against the side walls of the pipe. Keep cake build up to a minimum.
4) If you see any cracks developing in the inside walls of the pipe, make sure they are treated quickly by a restorer to prolong the life of your pipe. Once cracks break through to the outside - the problem is harder to fix.
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