finish MDO edge?

[bob]

I am building a cubbyhole cabinet with my daughter for a Girl Scout project. The cabinet will always be outdoors so we are building it out of MDO. I'm wondering if I need to put some edging over the exposed edges of the plywood (perhaps an "outdoor" wood like mahogany) or if I can just prime and paint. We'd like the cabinet to last many years without deteriorating too much. I'm located in the Deep South (Alabama) where the summers are hot and humid and the winters are mild - rain, cold temps to 20's, but no snow.

Thoughts - edging or not?

Thanks.

[Ron Magen]

Bob, MDO is simply a 'sophisticated plywood'.

While designed for outdoor 'signage', it has also developed a following with wooden boat builders. As with any plywood, the exposed edge is the most vulnerable.

The most preferred approach is to seal it by applying at two coats of 'unfilled' epoxy. This is then followed by two coats of paint to protect the epoxy from 'UV' degradation.

In your case, if the surface doesn't have to be perfectly smooth, treat it like any 'new' wood. A couple of coats of exterior primer {KILZ 2 - for water based} - lightly sand between coats. Then follow with a couple of coats of exterior finish.

Did a Rose Arbor for Joanne a couple of years ago - Western Red Cedar. 3 coats of primer & 3 of White finish - HD's 'house brand' Acrylic. Still looks new.

Regards & Good Luck, Ron Magen Backyard Boatshop