<!doctype html public "-//W3C//DTD W3 HTML//EN"> <html><head><style type="text/css"></style><title>Re: Wood Drying</title></head><body> <blockquote type="cite" cite>Terry,<br> <br> Your most immediate danger is too rapid drying through the end grain.  THe<br> dimensioinal change from differential drying through the end can create<br> checking that will make large sections of wood unusable.  Don't waste a<br> second getting some form of moisture-impervious sealant into the end of</blockquote> <blockquote type="cite" cite>every piece.  Melted parafin wax works best, IMHO.</blockquote> <div><br></div> <div>Or, if you have any wood glue<font color="#0000FF"> (out of date Titebond or rubbish PVA)</font> lying about, that works very well also. When sourcing local logs, we specify that the log is end-sealed as soon as it is cut.</div> <div><br></div> <div>Your idea of breaking the log down into 1/2" boards is a good one. Such boards will be ready to use in one year with just air drying<font color="#0000FF"> (ie. for the panel, rib stock will take at least two years, unless you plan to make laminated ribs out of the 1/2" boards)</font>. When we break down a log for sound board material, after the large boards<font color="#0000FF"> (2" thick)</font> have been cut out, we break down all the small triangular flitchs into 1/2" wide boards, so as to obtain the maximum of useable spruce from the log<font color="#0000FF"> (you will need a resaw with a tilting table for this purpose)</font>. The danger with drying is moisture gradients. Therefore, the thinner cut boards will tend to have less of a gradient problem, but they will be more prone to warpage. As soon as you have cut your boards, they should be stacked with spacing sticks (of say 25 mm by 25 mm section) between each layer of boards, spaced at about 300 mm (1') for boards 1" or thicker. I would recommend that the spacing sticks be set somewhat closer together for 1/2" boards to reduce warpage. The entire stack should be covered with some kind of roofing material and weighted on top<font color="#0000FF"> (house bricks will do)</font> to ensure that the upper boards in the stack are held down to prevent them from warping. Don't make the stack too high or the overall weight will cause the lower boards to sustain crush damage adjacent to the spacer sticks.</div> <div><br></div> <div>I'll photograph the drying stack I have at the house and send you a jpeg. Looking at your location Terry<font color="#0000FF"> (27 degress N, - I notice that you have another Sydney a few miles east)</font>, I would recommend that you commence the drying process during the winter months, since the summer heat will be very risky for freshly sawn boards. It is the initial drying phase during which degrade from moisture gradients is more likely to occur. Furthermore, quarter cut boards will tend to lose moisture faster through the edge of the board compared to the quartered face. This will occur with a quarter cut board since the medullary rays will be perpendicular to the edge and parallel to the board face. We seal the edges of quarter cut boards as soon as they come off the saw. This will greatly reduce the risk of stress damage at the edge of a quarter cut board during the drying process. I have noticed a tendency for belly wood to be more prone to compression set damage adjacent to the board joints. While there may be a multitude of reasons why this might be so, I have long suspected that the tendency for quarter cut boards to lose moisture faster through the edge, particularly during the initial drying phase, to be a factor here.</div> <div><br></div> <div>By the way folks, our new sound board conditioning box is coming along nicely<font color="#0000FF"> (the new box is big enough to accommodate a Bösendorfer Imperial board)</font>. If anyone is interested I'll be taking a photo of the assembly prior to fixing the last side of the box, so that you can view the layout of the air ducting. I'll put in on the web site and let you know when it is up.</div> <div><br></div> <div>Best,</div> <div>Ron O.</div> <x-sigsep><pre>-- </pre></x-sigsep> <div>_______________________<br> <br> OVERS PIANOS - SYDNEY<br> Grand Piano Manufacturers<br> <br> Web: http://overspianos.com.au<br> mailto:info@overspianos.com.au<br> _______________________</div> </body> </html>