When sawing panels to size, handle the sheets in a way that splintering occurs on the back face only. Using a handsaw this is attained by working with the good face up. When cutting on a circular bench or table saw, the good face must also be up. However, when using a portable circular saw or with an overhead radial arm saw the good face should always be down because the teeth cut from the opposite direction.
When it is crucial to get a clean cut on the back side as well as on the face, splintering can be brought downby first scoring deeply on the line of cut, with a sharp knife or a chisel. A different way to minimize splintering is to back up the sheet on the line of cut by clamping or temporarily nailing on a scrap piece of plywood or other lumber. You can then cut through both at once. Splintering would occur on the scrap lumber rather than on the back side of the plywood panel.
Irrespective of the type of saw being used (hand or power), a sharp blade having teeth with as little set as possible must be used. For hand sawing, select a crosscut saw with fine teeth and hold it at a low angle to the surface. Power saw blades must be of the combination type, while hollow-ground blades testament give the smoothest cut of all. For best results, set the depth of a circular saw blade so that it just projects through the thickness of the plywood.
To minimize splitting when drilling holes, back up plywood panels using scrap pieces of lumber wherever possible. This scrap must be clamped or nailed tightly to the back side of the panel. It allows the cutting bit to pull clear through the plywood without splintering on the back. Any splintering that occurs will happen on the scrap lumber instead.
To minimize chipping when edges should be planed, always work from both ends in towards
To minimize the problem of finishing or otherwise treating plywood edges, units must be made so that edges are hidden wherever possible. Mitered joints or rabbeted joints will do the trick, but both these techniques require power tools and careful fitting. An easier method consists of creating a simple butt joint (glue should be used together with the nails or screws), then covering the exposed edge using a thin wood veneer. This can be bought in flexible tape form, and it can just be glued onto the edge of the plywood with contact cement or other adhesive.
Another simple way to conceal edges if paint will be used for a final finish is to fill the exposed end grain using putty or spackling compound. These are available in both ready-mixed and powder form. Smear them on generously and allow to dry, then sand smooth using fine sandpaper.
Edges can also be hidden effectively with moldings or solid wood strips that are nailed and glued into place. Even simpler to utilize are the special veneer-faced aluminum moldings which allow joining of panels either at right angles or end-to-end without edges becoming visible. Primarily made for use with hardwood paneling, these moldings are nailed directly to the supporting studs or framework. They hold panels securely by locking onto the edges. They eliminate virtually all need for nailing through the edges, and hence save on the job of countersinking and puttying.