In our case work we many times use veneered
plywood for structural pieces. It is
available from ¼” to ¾” in birch, cherry, red/white oak, maple, mahogany,
pine, walnut, teak and a few other veneers by special order.
When you use plywood, the dilemma is always what to do with the exposed laminated edge. Everyone’s goal is to make the edge look like
the continuation of the veneered surface. You
can do this with veneer tape or more complex edge treatments that will require different
joining techniques.
We use the four following techniques for different applications in our shop…
IRON ON VENEER TAPE
Veneer tape, also called edge tape is 13/16” wide and will cover
all ¾” plywood. It is sold in rolls
from 25’ for small shops to 250’ for production edge banders. It is available in a number of wood species to fit
almost any project. Because it is so thin it
isn’t suitable for edges that will receive hard use.
But once applied properly the seams are virtually invisible.
A standard household iron is the tool of choice to apply the banding. Set the iron on medium heat. While it is heating up cut the lengths of banding
to size and allow a bit extra to overhang. Move
the iron slowly back and forth applying a steady pressure until the heat sensitive glue
melts and bonds to the plywood edge. The glue
needs to cool, before trimming and a good spring loaded edge trimmer does a great job
trimming the edges.
SOLID CAP EDGE
Solid caps will allow thicker edges. Most time a ¼” thick strip will work well. We use a 50-tooth carbide blade to rip material. Before ripping the next piece join the edge and be sure to use a push stick to prevent the thin strips from becoming trapped between the blade and the fence.
We use 3M clear plastic strapping tape 2” wide to join the cap to the edge. This tape has a lot of stretch and will do a much better job of holding the strip to the plywood than masking tape. After the glue has dried, trim the edges with a block plane and a cabinet scraper. Use care with the block plane, as the veneer is very thin. An alternative method to the plane is to use a small laminate router with a flush cutting bit with a bearing. This assures a very smooth edge and eliminates the risk of nicking the thin veneer of the plywood.
TONGUE & GROOVE EDGE
This edge can be a bit of a challenge to cut because of the setup time needed to center the groove in the plywood and cut the tongue to fit properly. One of the great advantages of this cap is that it will allow you to add detail to the edge such as a bevel, bullnose or an ogee detail. Start by plowing the groove in the plywood using a stacked dadoe blade set. Most ¾” plywood is not ¾” and plowing the groove from both sides of the board assures that it will be properly centered
The hardwood cap should have the shoulders cut with the edge of the stock flat on the tablesaw. Then turn the stock to the vertical position and run it through the blade again to cut the tongue to size. Because of the length of the cap, secure it either with the strapping tape or clamps as needed. Trim the edges as needed when the cap is dry.
THE CLASSIC “V” EDGE
This is the perfect edge for all fine furniture as it has an almost invisible seam, and the center offers more support than a solid edge. Machine the solid wood first to fit the thickness of the plywood. Mark the exact center of the solid material and then transfer that mark to a sacrificial plywood fence on your table saw. Set the blade angle to 25 degrees and set up the fence so that the spinning blade moves into the fence just below the marked line that you transferred from the solid material.
To cut the V shape in the plywood leave the blade at the 25 degree and shift the plywood fence to the other side of the blade. As with any setup that needs adjustment to fit, start with a scrap piece until the cut is aligned. When done, rip the cap off and use the packing tape to secure to the edge. This method makes a joint that shows very little hardwood at the edge where the veneer meets.