Seasoning green timber

[MaccDave]

Hi. In June 2005 I took advantage of some nearby tree felling and claimed some pieces of beech for woodturning, the best piece being a burr that was chain-sawed off the side of a felled trunk. All the pieces had their cut faces and end-grain well sealed with gloss paint and the pile has been loosely stacked in my garage since.

I noticed last week that the burr has a patchy area of white fungus breaking through the layer of paint, and I don't know what to do about it. The idea of having a spalted burr is great, but I don't want my prize find to simply rot away! Any suggestions on how to keep this timber usable would be very much appreciated - it's about 6 inches thick so I've got to let it season for a few years yet...

Thanks in advance!

 

[Scrit]

All the pieces had their cut faces and end-grain well sealed with gloss paint and the pile has been loosely stacked in my garage since.

So what you are saying is that the timber is completely coccooned in paint (and so it won't be able to lose any moisture at all) in an environment with no air flow (so even if it does lose moisture, there's nowhere for the moisture to dissipate) where the RH (relative humidity) goes up tremendouslky every time you put your car away on a rainy day....... And you haven't mentioned sticking, yet.

I noticed last week that the burr has a patchy area of white fungus breaking through the layer of paint, and I don't know what to do about it.

Strip the paint off everything EXCEPT the ends. Move the timber outside to a place which gets some airflow, raise it off the ground on blocks then sticker it at 18in to 2ft intervals on 1 x 1in rough sawn pine stickers - the rows of stickers must be vertical otherwise you'll get excessive warping during drying. Sheet over with some corrugated iron, leaving the ends open (the idea is that the rain can't lie on the timber, but that the wind can carry the moisture away). 1 year to 18 months outside for every inch of thickness (so unless you want it for turning - which would be best roughed in the green anyway as it is softer and MUCH easier to work - you'll speed the process up considerably if you have it resawn to useable thicknesses, say 1in or 2in. 6in in is really an unusable thickness as the centre will always be wetter than the outside, and if you were to rip a 6in thick piece into 3 off 2in thick pieces, the two outer pieces would in all probabality cup in the length overnight, if not sooner, and certainly in service! Air drying will bring it down to equilibrium with the outside air, about 14 to 16% MC (moisture content). BTW, do you have a timber moisture meter? To get it useable inside a house either requires kilning, or moving inside the shed, then the workshop and finally your house - each move should be to a progressively warmer/drier environment until the MC is in equilibrium with ypour house (probably somewhere between 6 and 9% MC).

The idea of having a spalted burr is great, but I don't want my prize find to simply rot away!

Burrs are generally the result of fungal action within the living tree. Spalts are caused by fungal action after the tree has died and because the moisture level is too high. You need to let the timber breathe to get the MC down or it will just rot away.

Scrit

 

[anobium]

Just like to commend Scrit on his excellent answer to Maccdaves question.
10/10.

 

[JohnD]

I think 9/10.

he missed that MaccDave said "cut faces and end-grain well sealed" not "sealed all over"

 

[Jasonb]

Personally I tend to turn the wood green to a wall thickness about 10% of the finished dia so for a 10" bowl I would leave the sides 1" thick.

Next place the turning in a large plastic (preferably clear) , seal with an elastic band and store it in a heated room. After 24hrs the wood will have sweated and there will be condensation on the inside of the bag. Turn the bag insideout, place the timber in it and reseal. Open again after 24hrs and repeat for a couple of months until there is no condensation on the bag.

At this stage leave the timber in a spare room for a couple of months more and then finish turn.

The bag method allows the wood to dry but as it is in a warm moist bag it only looses moisture at a controlled rate.

If you leave a big chunk of wood to naturally airdry it will be too slow for a timber like beech which readily spalts, you must get the MC to below 25% to make the spores dormant.

All the spalted stuff in this album was treated as above including the flat boards for the boxes.

Jason

 

[Scrit]

To add to what Jason said, my late father used to rough out his shapes in the green then pack blanks in fertilizer sacks filled with dry shavings and sealed. I know that he would periodically examine and discard warped items but that he would frequently hold stuff for one to three years before finish turning. Unfortunately I don't turn enough myself to be able to comment on the efficacy of this approach

Scrit

 

[MaccDave]

Hi,

Thanks for all your advice and suggestions. I wanted to keep the piece as a single block to make a large bowl, so I reckon I'll go ahead with roughing it out while it's green and let it season like that... I now have a better idea of what to do with the rest of my wood pile too!

 

[WoodYouLike]

I now have a better idea of what to do with the rest of my wood pile too!

cutlery?