Finishes for pallet wood items

[Peelster]

Hi,

I've been combing through the Internet with no real clear advice for my problem. I make quite a lot of things from wood recycled for old pallets. I sand all the planks down and try and allow for as much drying time as possible. After making items such as small boxes, I give it a light stain, allow to dry and then finish with a beeswax. But after some time I still notice a certain amount of shrinkage in the components that aren't fixed on all sides for example the lid. I was hoping there might be a sort of all round finish that seals the wood reducing shrinkage or warping.

I've not only had the problem with pallet wood but also an oak box that I made the two piece I glued side by side to make the lid are beginning to rise in the middle of the joint. I finished this item with Danish oil.

Any help or advice would be massively appreciated.

Thank you

 

[marcros]

this sounds more like seasonal movement than drying issues. For starters, I would bring the timber indoors for a period of time, so that it acclimatises to the environment it will live in, prior to final sizing. You can do this when it is cleaned up, but before cutting to final size. It may warp a little, but then you can dimension it afterwards and it should remain flat after that. You could also design your items so that movement is allowed for. For example having a floating panel in a lid component, so if you get a little movement in the panel, it cannot be seen.

To be honest, the worst thing that you could do is try and seal the excess moisture in. Inevitably it won't work anyway.

 

[ED65]

I was hoping there might be a sort of all round finish that seals the wood reducing shrinkage or warping.

Realistically you don't need to do this, you need to identify where the problem in the wood comes from and sort that out. You can seal wood off from atmospheric conditions pretty much completely but this is almost never done on indoor items because it's not really needed, and since it requires a very thick coating of something impermeable like an epoxy finish it's pretty expensive to do.

The issue here is with the wood. Pallet wood can't be guaranteed to have been well dried and stable before assembly and who knows what has happened to it since it was all put together?

Unless you're building something quite rustic with large tolerances and no tight joints once you strip a pallet apart you should acclimate the boards indoors for at least a couple of weeks before you use any of them. I've had pallet members bow and twist alarmingly, even though the wood was taken from a pallet that seemed completely dry and it was broken down in good weather.

But after letting the wood stabilise indoors for a period the material should be perfectly reasonable to work with.

I've not only had the problem with pallet wood but also an oak box that I made the two piece I glued side by side to make the lid are beginning to rise in the middle of the joint. I finished this item with Danish oil.

How carefully did you joint the edges of the boards? Is the lid a tight fit in its opening, maybe a little tighter than when you first built the box?

As marcros says, wood does naturally 'move', that is it expands and contracts as moisture levels go up and down. Some allowance does need to be made for it in most anything made from wood, and pine and a few other similar softwoods move more than many other species so bear that in mind with the pallet wood especially.

 

[timber]

I was hoping there might be a sort of all round finish that seals the wood reducing shrinkage or warping.

Realistically you don't need to do this, you need to identify where the problem in the wood comes from and sort that out. You can seal wood off from atmospheric conditions pretty much completely but this is almost never done on indoor items because it's not really needed, and since it requires a very thick coating of something impermeable like an epoxy finish it's pretty expensive to do.

The issue here is with the wood. Pallet wood can't be guaranteed to have been well dried and stable before assembly and who knows what has happened to it since it was all put together?

Unless you're building something quite rustic with large tolerances and no tight joints once you strip a pallet apart you should acclimate the boards indoors for at least a couple of weeks before you use any of them. I've had pallet members bow and twist alarmingly, even though the wood was taken from a pallet that seemed completely dry and it was broken down in good weather.

But after letting the wood stabilise indoors for a period the material should be perfectly reasonable to work with.

I've not only had the problem with pallet wood but also an oak box that I made the two piece I glued side by side to make the lid are beginning to rise in the middle of the joint. I finished this item with Danish oil.

How carefully did you joint the edges of the boards? Is the lid a tight fit in its opening, maybe a little tighter than when you first built the box?

As marcros says, wood does naturally 'move', that is it expands and contracts as moisture levels go up and down. Some allowance does need to be made for it in most anything made from wood, and pine and a few other similar softwoods move more than many other species so bear that in mind with the pallet wood especially.

The best way would be to treat the boards as fresh sawn i:e Stick and air dry, or if inside, a gentle airflow using an electric fan on warm air setting might help. Just make sure your sticks are dry and all the same size

 

[Peelster]

Thank you to you all for your advice. I'm currently storing all my wood in a unit environment which is kept out of elements but with the cold and then increase in temp we sometimes get some condensation in there which is not helping dry out the wood :? . We have a dehumidifier going to hopefully reduce some of the effects but i suppose we just need to wait and hope it drys out enough to work with.

Thanks again for the help!

 

[blackrodd]

You need to watch out with the dehumidifier, and to be aware of the current Moisture Content of the atmosphere and the wood in it, if it has pallet wood that has likely been in a wet yard or whatever and newer wood of varying m/c all mixed up, this may be some of you're problem.
Wood will suck up moisture 100 times faster in end grain, so could be very high mc after life in a puddle.
If you are organised, get one batch in stick, and to 10%-15% mc , separate and use this up, don't allow it to be contaminated by another batch of timber
Regards Rodders