A few questions about the best way to dry wood!

[jamesd]

I have finally managed to get some time to try out my alaskan mill which i brought about a month ago!

I've already milled a bit of beech and some oak and am very happy with the results, but now i've got some planks i have a few questions about the best way to dry them! So here goes:

 

1) Should you only stack the same species of wood in one pile or does it not matter?

2) How thick should the stickers be between boards and how should you space them out along the boards?

3) What should the stickers be made from? I have some pine skirting that i was thinking of using as its bone dry and all the same thickness.

4) What the best way to stack the boards? As high as possible with as much weight as possible?

5) I am planning on storing the boards in a barn will this be ok?

 

Any help would be great guys! Its my first go at milling so just trying to get clued up really!

 

Cheers, James.

[agg221]

1) Should you only stack the same species of wood in one pile or does it not matter?

 

Doesn't matter, so long as everything is about the same width. When stacking, try to either 'rebuild' the tree, or stack the widest boards at the bottom and work upwards with narrowing boards if you are stacking multiple trees above one another. That way you keep pressure across the whole board width which reduces cupping.

 

2) How thick should the stickers be between boards and how should you space them out along the boards?

 

Opinions vary. I don't find I have problems spacing every 2' and leaving the last foot of each board unsupported, others use more stickers. Thickness depends on species, time of year and width of board, based on theory and some experience, rather than very solid evidence, but it doesn't do any harm. If the stickers get too thin then air doesn't circulate well, if they are too thick at the wrong time of year it causes too much circulation and you get cracking or case hardening. Thicker stickers also means the stack gets taller more quickly so you need more space. Oak is particularly prone to surface checking if dried too quickly which means warmer weather, so milled in November-February when it's cold and damp I would use around 3/4" for 2-3' wide boards, but might go as thin as 3/8" if stacking 18" wide boards in June.

 

This makes it sound rather complicated - in practice it isn't as I just rip up some pallets and run them through the thicknesser if necessary to create a suitable pile. I reckon it's about an hour's work to make enough for a big tree (it took me that long to sort the stickers for the oak milled in Putney a few months back - 2off 10' lengths, lower length 4' dia, upper length 3' dia).

 

3) What should the stickers be made from? I have some pine skirting that i was thinking of using as its bone dry and all the same thickness.

 

Bone dry and same thickness are about the only requirements (although see comment on thickness above). Some use poplar, some use pine, I make mine by breaking down old pallets. Anything cheap, dry and available.

 

4) What the best way to stack the boards? As high as possible with as much weight as possible?

 

Yep, exactly as you state, so long as the floor is solid and the stack won't sink in. If you are stacking single trees, ie boards around 2' wide, the stacks start to get unstable above about 4', so I tend to run long stickers between adjacent stacks every couple of feet up. That way they stabilise each other and I can go as high as I can stack.

 

5) I am planning on storing the boards in a barn will this be ok?

 

So long as it has good ventilation and you stack them with an air gap to separate the stack from the walls if they're solid then this is ideal conditions and means you won't need to cover the stack.

 

Hope this helps.

 

Alec

[jamesd]

Ok thanks, thats really helpful.

I'm currently milling oak at 1.5 inches thick with a max width of boards at about 22 inches. What size stickers would you go for? i was thinking about 3/4 of an inch maximum?

I'm more worried about them drying to fast tin a barn as they may split so i've heard thinner stickers is better?

 

The other question is i have a lot of oak to mill and i want a variety of boards so what sort of sizes/thicknesses would you mill?

 

Thanks again, James.

[Big J]

Very good advice from Alec (as usual), but just two points I'd add (or perhaps even mildly disagree on!).

 

I stick every 18 inches, religiously. Sometimes that isn't enough and you'll still get movement. Perhaps it's sometimes more than enough, but you can't get a flat board flatter, so I'm happy to take that extra time as an insurance policy. I also reckon it's very important to stick right at the end of every board. It's incredible how much an unsupported board can move, in addition to which it helps reduce end checking.

 

I also don't like log form stacks. The reason is that all the boards above the centre are inclined to cup up, all those below to cup down. There are no oppositional forces and I dislike that. Build big stacks and try to flip the boards around. That way you've lots of oppositional drying stresses pushing in all sorts of different directions and movement is minimised.

 

Have fun!

 

Jonathan

[Stephen Blair]

Can I jump on here please?

I've recently moved a lot of milled timber for a customer , they were stacked well and covered in polythene.

There were holes in the polythene and quite a lot of the top boards have rotted and were damp .

I've re located the timber in a very windy place and have not re covered them .

Am I best to leave as is or remove damaged timber and cover with fresh tarps?

Thanks

[Peat]

I've heard of people ratchet strapping their stacks to minimise cupping. has anyone tried this? Worth doing?

[jamesd]

Very good advice from Alec (as usual), but just two points I'd add (or perhaps even mildly disagree on!).

 

I stick every 18 inches, religiously. Sometimes that isn't enough and you'll still get movement. Perhaps it's sometimes more than enough, but you can't get a flat board flatter, so I'm happy to take that extra time as an insurance policy. I also reckon it's very important to stick right at the end of every board. It's incredible how much an unsupported board can move, in addition to which it helps reduce end checking.

 

I also don't like log form stacks. The reason is that all the boards above the centre are inclined to cup up, all those below to cup down. There are no oppositional forces and I dislike that. Build big stacks and try to flip the boards around. That way you've lots of oppositional drying stresses pushing in all sorts of different directions and movement is minimised.

 

Have fun!

 

Jonathan

 

Cheers for the advice, so you would stack in any order then or would you start with larger boards at the bottom then smaller boards at the top? but you would also mix the boards up from different logs as well so if they are likely to move when drying they won't all try and move the same way i guess?

Also what thickness stickers are you using?

[jamesd]

Also ahs anyone got a picture of their stacks?

[Mike Dempsey]

I ratchet strap my boards very carefully. I did about 6 or 7 loads through my sauno kiln and every load was ratcheted down. I broke the kiln up last year as I wasn't happy with it and I am now in the process of designing and building a new one. I am going to buy marine grade stainless steel ratchets this time.

BTW I have only ever used 10mm thick stickers which are 40mm wide and made from douglass fir. I have kiln dried oak, yew, beech, elm, ash, birch and walnut and used the 10mm ones regardless of the timber or the thickness of the planks

[Big J]

 

Don't pay attention to the top stack - it was only there temporarily. You want all stickers and bearers to line up.

 

I mix up the board widths throughout the stack, no real order really. I use 18mm or 22mm stickers. All my stacks are in barns with moderate to good air flow and no direct sunlight.

 

Jonathan