A slice of an Oak tree

[okeydokey]

A couple of tall oak trees estimated age 100/130 years old are being removed (not by me and I hate they're going - a property developer in a field near me) in a few days when I won't be around.
I suspect the trunks are going to make oak beams somewhere and Ive asked if they would leave me a couple of slices say 3" thick, they will be about 3 foot diameter any suggestion what I can make with them please? or how to stop them going pop and splitting all over the place beforehand.

 

[Orraloon]

If its crosscut slices (rounds) they will split. Also they have next to no structural strength so anything you make will need propper support. It would be best to paint both sides as soon as possible to slow down the drying and leave a couple of years to dry out under cover. There will likely still be cracks but something like butterfly inserts holding a crack together can look good.
Regards
John

 

[Phil Pascoe]

I would be tempted to put a cut in them from the pith outwards. They will split anyway, so at least you can choose the curve and position of your cut.

 

[Jones]

A round slice of oak can't dry without splits forming. You might be able to choose where they go by starting them off with a saw cut. I can't see treating the cut ends would make much difference to splitting but will lengthen drying time.

 

[JDW]

Out of interest, are there any species that don't split and the 'rounds' can be used?

 

[Sgian Dubh]

Out of interest, are there any species that don't split and the 'rounds' can be used?

Generally I'd say that ~98%+ of end section discs develop at least one radial split during drying, and more often than not there are multiple splits, i.e., two to four major ones. The cause is the differential shrinkage found between the circumferential shrinkage of the growth rings which is typically approximately twice that found in the shrinkage radially, i.e., across the growth rings.

To try and prevent such radial splits in an end section disc one method that might be worth exploring would be to try replacement bulking chemicals such as pentacryl and polyethylene glycol (PEG). They replace the water and minerals in the cell lumen to prevent shrinkage. I've never tried it myself - never wanted to or needed to, but these are chemicals that some woodworkers turn to from time to time, e.g., turners. Slainte.

 

[accipiter]

Just an idea to maybe think about and consider. If they're going to be about 3ft diameter then maybe putting something around the edges to restrain any splitting tendencies/movement? Something like luggage ratchet straps so you can adjust/tighten as the rounds dry. Store in a cool dark dry place covered to slow down the drying process... and check regularly to tighten the straps.

As to what to make... table tops come to mind. If they do split then the splits could be filled with resin or (as put forward by @Orraloon ) make some butterfly/dovetail inserts - or a combination of both.

 

[TRITON]

I have seen something years ago about using a leather strap, pre-soaked and wrapped tightly around the circumference of a log slice, so when the leather dries it tightens.
I dont think you'll be getting such a belt 10' long, but maybe in joined sections and wrapped that way. You pin it one end, then wrap,keeping it very tight, then pin it the other.
I have no idea if this would work. But over the years i have seen fairly large crosscut section that weren't all split apart, so the idea or having something that allowed it to dry and not split must be out there.

 

[Phil Pascoe]

If you've seen a slice that hasn't split, I wonder it was cut from a bole already seasoned?

 

[okeydokey]

Thanks all
I like the idea a making a cut it might take some stress out of the drying process - perhaps wait until a crack has formed and then follow the crack line and see how it goes. Butterfly inserts in another colour might be good if one of them went the route of a crack then perhaps one could be a table - with 3 ??? legs made from one of the branches

 

[baldkev]

How about coating one of them fully with epoxy? Get the disc planed/ sanded etc, then maybe 3 coats of epoxy? Or suspend the disc in an epoxy pour, so its 10mm thick all round

 

[Inspector]

They are going to crack no matter what you do. You can reduce it somewhat by cutting out a hole (maybe 6") in the centre of the slab to allow the drying wood to contract. A vacuum drying kiln pulls the moisture out more evenly which also reduces the degradation. You don't have time to get one set up though. Dropping it in epoxy won't work because the wet wood inside will rot anyway. Encapsulated plant materials have to have as close to zero moisture content. Might as well let them crack as they want and celebrate the defects.

Pete