RE: [MedievalSawdust] Drying wood
- All wood has Lignum(noun:woody tissue)Barrels are made with White Oak only not Red for two reasons, tannin(give flavor and color) and its rot resistance. Cherry is some time used because of the tannin as well.The reason that Quarter sawn lumber is preferable over flat is in the orientation of the growth rings in the wood. This is true in any species of wood. Moisture is absorbed by surface contact with the growth rings, on a Flat sawn board the difference between the surfaces create absorption disparity(some species up to 25%). This causes cupping and warping of the board, and some twisting(some from the wood fibers direction). In a true Quarter sawn the growth rings are oriented perpendicular to the surface so moisture is absorbed evenly causing the wood to expand and contract(normally less than 6%) along it width but remain flat.Economics means that Flat sawn gives you more out of a log but it is less stable, true Quartered is much more stable but you get about 20% less out of the log. Now days what is called quartered sawn yields about 4 boards(the widest ones) that are true quartered and the rest are rift sawn, meaning the growth rings can move off the perpendicular by up to 30deg. some time leading to warping or twisting.In period it was common to leave the log till it started to naturally split, this relieve the stresses in the wood. You then start splitting wedge shapes from the outside into the center of the log to get pieces with the growth ring orientation you want. Now you plane down to get parallel surfaces the thickness you want, it's very time consuming and back braking.In ServiceHal
Date: Thu, 28 Feb 2013 01:02:02 -0600
Subject: Re: [MedievalSawdust] Drying woodA good point. And quarter sawn oak is used for barrel staves which puts the "legium or ligumen", a special component of oak, (which I know I have misspelled but is not "legume" (beans) which my spell checker suggests) in the right direction so the barrel doesn't leek. What I don't know is why quartered wood has less problems, do you?
On 2/27/2013 12:38 PM, D. Young wrote:Most furniture of quality was made from quartered wood.
I own an extensive collection of 15th - 18th century pieces *original* and most utilize quartered wood ....which is very stable.
I do believe logs were often given a year or so to dry out a bit...but that moisture remains for upwards of 10 years. IVe seen this in my own logs.
Two things to bear in mind....
Peasants and lower class folks had very little furniture. Log furniture basically. Not unlike what we might call "rustic" log stools and tables etc
But after circa 1200-1300 deforestation was so serious, it was deemed a priority as the Renaissance/Colonial period began
The explosion of furniture in the 17th century is due to North American and Baltic oaks being imported in huge quanities.
I guess my point here is that if you dont want splitting,. checking etc....ie, CRACKS.....you need to work with quartered wood.
However quartered wood is limited in size...if sawn you only get about 4 directions of the widest wood pie shapes in the form of a cross "+".....
Any other pie pieces (quartered) tends to be narrower....but it all depends on the oak tree, etc ....
We dont often get out hands on 4-6 food wide trees....so our panels are not often as wide as some of those insane hutch chests with 20 inch wide panels.
- rays.... quarter sawn parts are more stable because of the rays. these are structures that run from the pith out to the bark.
White oak is used for barrels not because of it's quarter sawn or ray character but because of it's tyloses and strength. it is stronger than other woods and the tyloses block the pores making it water proof. it is also favored for it's flavoring aspect.
the lack of tyloses is why you never see a red oak barrel.
i recommend reading or perusing "Understanding Wood" by Bruce Hoadley