Thread: slabbing

HI Van,

Welcome to the BB. Not sure what Melaluka is like to work with but one thing you should do is get some endcheck paint to cover end grain on the slabs etc. this will stop it splitting as it dries.
It dries to form a sort of waxy cover over the end of the timber.

By the way you will have plenty of time to think of uses for the timber as it dries, 100mm is about four inches. rule of thumb for air drying is one year for every inch of thickness plus one year. In your case roughly five years for the timber to dry.

You also have to stack the timber so that there is spaces between the boards, to allow air flow accross the greatest surface area possible. this is done by placing small sections of timber "stickers" between the slabs.



Himzo.

You arent the only one who doesnt know much about drying timber, only a bit from what I have seen on this board.

Who did your slabbing for you?

btw you are from a nice part of the Coast.

Van,
I had a couple of large Melaleuca Leucadendrons milled up a few years ago. It's a fairly featureless timber grain wise but its appearance has actually improved with age. It started off a slightly pinkish honey colour which has deepened over time and the grain has become more prominent. I built our dining table out of it. It was often used in the past for butcher's blocks as it apparently has natural antiseptic properties. Do a search on this BB as I've posted a picture of it and I did reply to some Q's about the timber.

Mick

Van

I can't help you on the Melaleuka species. However I would comment that 100mm thick is very thick for any species! Four to five years air drying is a good estimate. I would suggest that normally only burls should be cut this thick, because they have little inherent strength. 50mm to 60mm should be strong enough for most milled timbers and the drying time is probably halved.

The only way of cutting the timber down now would be to find someone with a large bandsaw mill as these only take a 1.5mm kerf. However the largest that I have encountered will only cut to 1350mm.(Laidlaw supermill). The slabbing attachments such as the lucas will cut this width but have a large kerf and large sideways forces and it can be difficult to resaw previously cut boards safely. You also have the problem of cutting the slab exactly in half. This is not the Lucas slabber's forte.

The problem with any timber is that it tends to cup. The wider the board, the more the tendency to cup is present. It is of course why tables are made out of boards rather than slabs.

Having said that, slabs are fabulous. To air dry them make sure your stickers are directly above each other and put stickers flush with the ends of the board. Normally two stickers are placed next to each other at the ends. This in conjunction with painting the end grain reduces the rate of drying at the board end and minimises the splitting that occurs.

The weight of a stack of boards will be enough for the lower boards but the top boards also require weight on them. Stacks for air drying are normally in the open to allow air flow through the stack but the tops in particular should be protected from direct sunlight. Those living on farms could use an old hay shed, but for most it will be a sheet of corrugated iron on top of the weight on top of the stack.

A personal theory of mine is that for slabs good air flow through the stack is essential to carry away the moisture. In drying conventional boards the timbers are placed directly over the top of each other four or five boards wide with a gap between them. This allows for moisture to 'fall' down between the boards. With a single large slab up to 1500mm wide this facility is non existent.

You can dry timber in a closed shed but without good air flow the drying will take longer again. Bear in mind that at the end of this process you will have only "air" dried the timber and moisture content will still be around 25%. You need to bring it to 12% approx (depending on where you live. Brisbane might be 13% or 14%, while Ayres Rock could be 8%!)

You will only bring it to this MC, in a reasonable period of time, by kiln drying. There is on the BB a discusion about solar kilns, and other types of kilns, which you may find useful. On the positive side, with a minimum of four years dring ahead of you, you will have plenty of time for research.

Let me know if I can help further.

Regards

Paul