FreeMDO Plywood: Medium Density Overlay for Paint
MDO plywood, medium density overlay, is exterior plywood with a resin-impregnated paper face bonded to one or both sides. The overlay is smooth, grain-free and stable, so paint goes on as flat as on MDF, but the sheet underneath is real exterior plywood with waterproof glue. It is the classic board for signs, painted outdoor furniture and painted cabinets.
Sizes and thicknesses
MDO plywood is sold in 4 × 8 ft sheets, overlaid on one side (MDO 1S) or both (MDO 2S), in 3/8, 1/2, 5/8 and 3/4 in thicknesses. Two-sided MDO is the choice for signs and panels seen from both sides.
Advantages
- Paints perfectly smooth, with no grain showing through
- Exterior glue: works outdoors when painted
- Lighter and stronger than MDF, holds screws like plywood
- Stays flat and does not check or crack
Drawbacks
- More expensive than plain exterior plywood
- Must be painted: the overlay is not a finish
- Edges show plywood layers and must be filled and sealed
- Not always stocked by small yards
What it is used for
- Signs and outdoor painted panels
- Painted cabinets and built-ins
- Outdoor furniture and planters that will be painted
- Cornhole boards and game boards
Tips for working with MDO plywood
- Prime with a good exterior primer, then two coats of paint.
- Fill and seal every edge before painting, especially outdoors.
- Cut with a fine blade; the overlay chips less than veneer.
Frequently asked questions
What is the difference between MDO and MDF?
MDO is plywood with a paper face and waterproof glue; MDF is fibreboard all the way through and swells when wet. Both paint smoothly, but only MDO works outdoors.
What is the difference between MDO and HDO plywood?
HDO (high density overlay) has a harder, heavier resin face that sheds concrete and water: it is used for concrete forms. MDO has a paintable face.
Is MDO plywood good for cornhole boards?
Yes: its face is smooth and flat, takes paint and decals well and stands up to being outdoors once painted and sealed.
Furniture plans to build
All plans →
Related guides
Cornhole Board DimensionsOfficial cornhole board dimensions: 24 × 48 in, a 6 in hole 9 in from the top, 12 in high at the back. Plus court distances, bag size and how to build the boards.How to Paint MDFHow to paint MDF for a smooth finish: seal the thirsty edges, use the right primer (not water-based on raw MDF), sand between coats and paint cabinets and furniture.