Not sure where to post this but I’ve been asked to make an exterior sign - 750x600mm.
I have been supplied the wood in the correct size but it’s green oak and 30mm thick. I’ve never used green oak and not done any outdoor signs before.
It’s made up of 3 horizontal planks glued up and is slightly cupped. I could surface the piece before engraving but will it last long outdoors before cracking/warping bearing in mind the Uk climate?
I have lots of flat 20mm white pine untreated furniture board (more in my comfort zone working wise) I could use but I know pine isn’t great outdoors unless there’s a super coating I could use. Thanks for any ideas.
There is not really a super coating that I know of. Most people will use a material commonly used for fence building: Cedar or PVC for exterior signage. . . Or CoraFoam or a High Density Urethane material which handle better in those environmental conditions than most other options.
I would avoid the pine unless you’re painting the whole thing and the owner intends to have it repainted annually.
Unfortunately I’m not familiar with Green Oak, but I would be weary of a panel glue up that I didn’t do myself as you wouldn’t really know if it was done right, whether its a basic edge glue, what type of glue was used, whether there are dominoes in it or not.
Not a ton of help, but someone elses opinion to think about. 
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it would be a mistake using green oak or fresh sawn oak under 18 months.
I would recommend white oak or go the extra mile and use teak.
only drawback would be, is that teak will put a big dent in your wallet.
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Thanks Guys! I’ll rethink this one! Good to get straight talking advice as always.
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Any green wood will warp and/or split when drying. Even while carving the heat of carving may make it move and vcarving could problematic.
It takes about 2 years to air dry 30mm oak. Using green wood will turn into a disaster. You can dry it some if it fits in a microwave oven or even a conventional oven but it is risky.
Hey guys, I think there might be a little confusion. Garry’s in the UK where there is actually a species of oak called “Evergreen Oak” this is a bit different than the “green” that we often refer to when speaking of freshly sawn wood.
So Maybe Garry can clarify is this “Green Oak” is actually a specific species name or if it’s actually freshly sawn oak, with a high moisture content 
Really appreciate the info here guys. Seth - thanks for taking the time to go into detail - it really helps. I’m still learning the cnc process which includes learning about wood types and their properties. I should’ve been more specific. In my case I’m referring to green as in, not fully dried. It’s probably cut 6 months ago and kept in aside a timber merchants store. I have a moisture meter and it reads 26% and is commonly used over here in outdoor construction projects in the garden for example. It’s too big for me to dry quickly. Sounds like trying to carve an outdoor sign out of this would result in some unusual curved lines of text after a while :-).
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Thanks for clarifying that! Yeah I wouldn’t suggest using it either not for an outdoor sign, the cut ends will most certainly split/check as it dries out especially with a panel glue up.
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