Drying an Oak slice

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caveman

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In the last gales a large Oak came down and is now being dismantled. I have been given a lovely "slice" to make a small coffee table from but how can I dry and seal it to prevent it from cracking please??
 

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Painting both faces with melted wax will help to reduce any cracking by slowing the drying process.

If you do get cracking, make them a feature by resin/contrasting wax filler or put a bowtie in?

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The chance of its not cracking is zilch. I think I would put one saw cut through to heart and accept you've got a gap to infil with another wood or resin. At least then you'd have only one "crack", exactly where you wanted it (away from where you want to put the legs?) - you could curve the cut if you wished. You may get away the small side.
 
Um, food for thought there PhilP! The man cutting the tree up said something about diluting PVA and painting both sides?
 
What size is it? The larger it is the more likely it is to crack. You can try coating it with PVA but it's unlikely to stop cracks - I've logs of 7" or 8" diameter that were well coated when first cut that have bad splits. Get your retaliation in first - if you cut it at least you know there's a good chance of there being only one. Not a flaw, a design opportunity.
 
The man cutting the tree up said something about diluting PVA and painting both sides?

Yerr, dat works in de short term :( ...try reposting on lathe section here, Robbo, Chas and the gang over there have vastly more experience in stabilising wet wood for finishing.

Sam
 
I use gloss paint, it forms a nice thick layer but doesn't soak in too much.

It will crack though, you can't stop that so plan to make a feature of them.
 
There is only a very small chance of that drying without splitting. Normally Wood is sawn into boards and the pith(heart) is removed as most splits begin there. You'r bit is crosscut with the pith in the center so not the good way to do things. Coating the end grain slows down the drying so slows the shrinking of the wood that is the cause of cracking but the end grain sealing should be done as soon as the wood is cut and even then no real guarantee. I have tried it at the prompting of a friend who wanted a slice of log table even after I pointed out the down side. Anyhow slice of log became firewood. Best you can do is wait a couple of years and see if you get lucky.
Regards
John
 
caveman":fgbsn40q said:
The man cutting the tree up said something about diluting PVA and painting both sides?
PVA (usually not thinned) is often given as a bodge for sealing end grain and to be fair it is better than nothing, but it would be pants compared to e.g. melted wax. You want to use something that's pretty much 100% waterproof and a thin layer of most things isn't; whatever you use you want to slop it on for maximum effectiveness.

Even if you do everything right though there's always a chance of a crack. If you take 100 rounds and within an hour of cutting coat the end grain with Anchorseal as per directions or a layer of melted wax, then put them somewhere they'll dry slowly you might still get cracks in over 50 of them.

The cracks tend to happen fairly quickly if they're going to happen at all, you won't have to wait the six months to a year + to find out whether the gamble paid off. So there's that.
 
Many thanks gentlemen, all most helpful. Don't have any wax other than furniture polish but could get some of the Anchorseal I think? Size wise, just 35cm X 65cm long so not too big.

I could indeed put a cut to the centre but have to be to each one I guess.
 
That is for sealing the ends of logs so the moisture comes out through the sides, relatively slowly, rather than through the ends, more quickly. (Think of the log as a bundle of hollow straws.)
With a thin slice, there isn't really any side, so the sealer won't help.

As already said, make a straight cut and join the two parts back together later, or make a decorative feature of the split.
 
Um, not sure how I'd cut it in half, only got a hand saw and the joint would always be vissible me thinks? Also, should I leave the bark on during drying, or take it off?
 
caveman":t5ixcvxm said:
Just planed off the chainsaw cut marks and ordered some of this "end sealer"!

https://www.amazon.co.uk/dp/B007HM1D5U/ref=pe_3187911_185740111_TE_item

Sorry but I doubt that will help, the end grain, and that is what you have in abundance, will start to split within seconds of cutting a green log through. Once started then the moisture loss from that area speeds up almost on a logarithmic scale. Sealing needs to be done immediately the cut is made.

If you look closely at your planed surface you should see the cracks widening on a daily basis if not an hourly one.


Don't take the bark off, although rather insignificant with a slice like that, taking the bark off only speeds up the moisture loss from the outer surface and encourages splitting from the outside of the log as the surface wood shrinks.

I think the only way you can get anything like a sensible recovery of log slices is to put them into a controlled environment drying kiln immediatly they are cut.
 
Umm, all doom and gloom :cry: Oh well, see what happens and work from there :wink:
 
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