Plywood is an extremely common timber material and one that is found in heavy use across industries. The relatively low cost of production, and the high yield rate in production, make it a cheap material for its remarkable durability. But there are many one-of-a-kind of plywood, as well as unique thicknesses and finishes. What are some of the extra typically used sorts of plywood?
The most commonplace varieties of plywood are created from sheets of softwood – commonly pine, but also other coniferous woods along with spruce or fir. These plywoods, due to the relative abundance of softwood, are reasonably priced to provide and cheap to shop for; due to their structural energy and inexpensiveness, they may be often used in construction.
Lower-grade softwood plywood is used for temporary concrete formworks in construction scenarios, as a strong and stable mold for concrete to fill. They can also be used for temporary structures and storage, and as packing in larger-scale manufacturing scenarios. Higher-grade SPF (Spruce-Pine-Fir) plywood is used for builds in production, such as with decking or subflooring in domestic creation.
Hardwood plywood is constructed from plies of deciduous woods, at the side of ash, oak, maple, beech, mahogany, and birch. Hardwood plywood is typically extra long-lasting than softwood plywood and is used accordingly – within the creation of fixtures and fittings.
Birch plywood is unique, though, in that it is much lighter than most other hardwoods and much easier to manipulate and form. Thin birch ply is commonly chosen for steam-bending and used to make furniture or finishings accordingly.
Marine plywood is a hardwearing material designed for use in humid or water-rich environments. Contrary to common assumptions, marine plywood is not a treated material; rather, thick hardwood plies are cross-laminated and heat-pressed, and adhered to one another using a waterproof adhesive. The result is a water-resistant (as opposed to waterproof) wood product that can be used in boatbuilding, particularly the building of decks.
MDO and HDO
MDO and HDO stand for medium-density overlay and high-density overlay respectively. The overlay is a phenolic fibrous resin, applied to the back and face of a given plywood sheet. MDO plywood has a waterproof but rough resinous surface, which can accept paint and prints; this is used commonly for all-weather signage. HDO plywood has a smoother, slick surface; this makes it an ideal material for reusable concrete formworks, owing to the ease of removal after the concrete has dried as well as the smooth surface it leaves behind.