Moisture content in Sapele

[vinnie_chip]

Hi, I just picked up this slab of sapele for £20 it measures roughly 1m x 1m x 5" tapering to 2". I plan on making a table top out of it (I think). My question is regarding moisture content... It is reading around 24%, how long will I have to leave it until it comes down to an acceptable level? Im thinking it needs to come down to about 12%. It will be stored in my garage which is warmish. The finished thickness will be around 2" so shall I leave it in its tapered state and machine it when the mc comes down? I may be wasting my time if it splits too much and falls to pieces but thought i'd give it a go..

 

[tomouse]

I would try to get it down to a rough even thickness first so that you are reducing the amount of timber you want to dry and thus the time involved. Also this will allow it to dry more evenly.

Drying without defects is a bit of a minefield. Warm is good but too warm and moisture will be drawn out to quickly and you will get defects such as checking and shakes. Too cold and drying will take forever. Most of the moisture leaves the timber through the end grain so it will dry fairly quickly but as mentioned before not a good thing. It might be worth painting the surfaces with pva or breathable paint to slow the process. To be honest drying timber in that orientation with splitting is going to be a challenge.

Good air flow is also very important so if you can put it somehwere where there is through flow of air all around the timber that will better your chances.

If it does split it's not the end of the world, you could always fill the splits with resin or cut it up and rejoin it.....

 

[Sgian Dubh]

That will dry quite quickly because it's a disc of wood from the trunk, so what's exposed is pretty much all end grain. The end grain, of course, is exposed cross section of vascular tissue, up and down which fluids were transported when the tree was living, a bit like bundled up drinking straws. Any free water should drain out quickly, and bound water should also dry out fairly quickly because those 'drinking straws' will allow air into the wood relatively easily.

Your biggest challenge will be preventing radial shakes developing as the wood dries. It's difficult to do that, but you could try using PEG or Pentacryl both of which are bulking agents that replace water lost from the cell lumen. Alternatively, you can accept that you're very likely to get radial splitting and try to control where a split occurs by running a saw cut from a chosen point(s) on the circumference to somewhere near the centre. If you're lucky this saw cut(s) will be the only place(s) you get a radial split and it (they) will open up nicely like the segment(s) of a circle. Slainte.

 

[andersonec]

If it hasn't split already then you stand a good chance of it not going any further, it usually splits within a few weeks of cutting. What may make it split is trying to hurry it and putting it somewhere too warm.
If you can locate a small firm on some industrial estate near you who package stuff up then they may put a steel strap around it for you, failing that, some small blocks every few inches the put on a tourniquet of strong steel wire and wind it up with a piece of steel rod.

Andy