How to dry "tree slices" ?

[Mike vonBuelow]

Ok, so I'm thinking about doing some laser engraving on tree slices and since I've never worked with these before, I'm needing some advice on how to prevent cracking.

http://www.sawmillcreek.org/attachment.php?attachmentid=167299&d=1289789454
Can I leave them in the garage, esp with colder weather here, to dry them?

How long for a 2"-3" thick slice to dry (typically)?

Does diameter matter (this one is appx 15")?

Do I need to seal them? Top & bottom only - or all sides? Or is that counter-productive?


Any ideas on how to preserve bark?

I'm not sure about finishing procedures at this point... may/may not include sanding, stain, poly coat...

[Prashun Patel]

You might take this question over to the Turners forum. But I can tell you that cross sectional cuts like this are incredibly prone to cracking. If it were me, I'd get the slabs covered quickly with Anchorseal and let them sit for a year + in a place like my basement.

[Ed Morgano]

Mike,
I've never used it but PEG will replace the water in green wood and keep it from shrinking. Here is a link with some information. http://en.wikipedia.org/wiki/Polyethylene_glycol. From what I've read, it will leave a sort of waxy surface so it can't be finished. Also, I've read that if you cut a tree in the winter (when the sap is down) the bark will stay on. Hope this helps.

[Mike vonBuelow]

Yes, thank you!

[Stephen Cherry]

Just an idea, but maybe you could cut your slice to the thickness that you want, then with a router, from the back, rout most of the wood out of it, leaving about 1/16-1/8 thickness for all but the perimiter.

Kind of a very flat bowl.

Then into the hollow of the bowl, glue a piece of plywood to keep things stable.

Never tried it, but maybe it would work. The whole idea would be to use the plywood to take up the stress, and keep the wood in place.

[Jonathan Spool]

I would think that some your success will be species dependent. for example, you will never be successful with a crossection of Madrona that includes th pith, but very likely to be if you use Monkey Puzzle. I have had luck turning bowls centered on the pith using pine as well as long as I soaked them in alcohol for a day, and dried them for a few weeks. For a 2" slab, try soaking in alcohol for a week in order to displace the water, wrap in brown paper and dry for a month and perhaps you can accomplish what yo are seeking. If you are succesful be sure to post your results!
Good luck!

[David Hostetler]

Log slice clocks are a popular item up in Oregon. Specifically using the Oregon Myrtlewood slices... I had a Myrtlewood clock that I ended up leaving with a friend when I moved from Oregon. I miss that clock, and that particular friend...

I seem to recall that the slices are cut from a seasoned log, using a chain saw jig that makes the slices thicker than the desired thickness. Then they are sanded smooth, the machining for the clock works, numbers etc.... gets completed, and then the whole slice gets a fairly heavy coating of lacquer. Then final assembly. I have also seen them done with that heavy clear resin stuff that gets used on bar tops and stuff. (don't recall what it is called right off the bat, hope you know what I mean though...).

Sorry, the clocks I dealt with in that method were made in the early to mid 1980s. A LOT of life has happened since then, and so memory might be a little fuzzy...

[Rick Prosser]

Maybe you use whatever method to dry as best as possible, and then fill in any cracks with epoxy - or just leave them for a more rustic look?

[Mike vonBuelow]

Thanks all - looks like pith removal (replaced at a later point) and DNA soak/dry will be my choice - results to follow