gluing up a KDAT slab?

[Garrick]

I'm making a couple of 10 foot long wooden slab tables for a restaurant patio. They will be subjected to heavy use and the elements. 

I was thinking of using biscuits and gluing up the slabs out of Kild Dried After Treatment PT lumber.  Does anyone have experience and advice for trying this?

[jteneyck]

Why glue them up at all?  Kiln dried pressure treated lumber isn't really dry, but it is better than the sopping wet stuff.  Still, if you glue the boards together there is going to be a lot of shrinkage as it eventually dries.  If you want to use KDAT lumber I would consider building the tops like a picnic table with 1/8" gaps between the boards.  If you want a higher end look or a truly solid, glued up top then I would use white oak, cypress, larch, cedar, or some other inherently rot resistant and kiln dried wood. 

If you do decide to glue up the KDAT boards you will need to use Gorilla Glue or some other glue that bonds to wet wood.  If you use any of the other truly kiln dried woods then you could use any exterior rated glue, like Titebond III, Gorilla Glue, or epoxy.   

John

[Garrick]

I was considering white oak as my other option. In the past I've made oak slabs for restaurants and no matter how much I emphasize that exterior wood surfaces will need some upkeep, the tables get neglected and suffer from the elements and the heavy usage in a restaurant environment. 

I guess I was hoping I could "fake" the higher end seamless slab look with the KDAT lumber and hopefully wind up with a table that's maybe not quite as pretty but could withstand some abuse and neglect. I'm not sure if shrinking/movement would lead to the table being just a little wonky (acceptable) or disastrous (less acceptable.)

If I do go this route I'll definitely go with Gorilla Glue. Brain keeps switching back and forth.

[jteneyck]

I was considering white oak as my other option. In the past I've made oak slabs for restaurants and no matter how much I emphasize that exterior wood surfaces will need some upkeep, the tables get neglected and suffer from the elements and the heavy usage in a restaurant environment. 

I guess I was hoping I could "fake" the higher end seamless slab look with the KDAT lumber and hopefully wind up with a table that's maybe not quite as pretty but could withstand some abuse and neglect. I'm not sure if shrinking/movement would lead to the table being just a little wonky (acceptable) or disastrous (less acceptable.)

If I do go this route I'll definitely go with Gorilla Glue. Brain keeps switching back and forth.

No wood does well outdoors w/o some regular maintenance.  Even pressure treated will look poor without regular cleaning, as a minimum.  And you are right about white oak; it can turn into a black moldy mess if it's not cleaned regularly.  Wood outdoors and no maintenance is an oxymoron.  

John

[Arlin Eastman]

glue up with epoxy and use the same for all the rest including the bottom and sides.  nice to look at and water proof

[jteneyck]

glue up with epoxy and use the same for all the rest including the bottom and sides.  nice to look at and water proof

Most epoxies will not bond to wet wood.  System Three makes one that will, IIRC. 

John

[kurt18947]

Is there any concern about using P.T. wood for a table top for food? I know there's not as much arsenic in P.T. wood as there used to be but still. Certainly for the structure P.T. would be fine and yes food would not be placed directly on the table top, just thinking out loud.

[K. L. McReynolds]

Using PT lumber anywhere close to constant human contact(bare skin) is not a good idea and around food even less so. The chemicals used in modern PT wood are less immediately harmful to humans, but allergies can be a problem. There are chemicals that are harmful to insects, for instance.

White oak is an option, but does need some maintenance. Splinters could also be a problem.

 How about cedar? Rounding over all edges would minimize any splinter problem and much less maintenance would be necessary.

Not a good idea to edge join planks of any wood that is used outside in the weather in my experience.