Scarfing, oh the joys of joining two long pieces of wood into an even longer piece of wood. There are many methods to scarfing plywood; The traditional, hand plane method, the Belt Sander method, the circular-saw-on-a-jig method, and the Router Jig method. We’ve tried them all. With the wood layers as a guide, all work, though some more labor intensive than others. We’ve just recently acquired a new Shaper Origin, which is a Hand Held CNC router and when it comes to our next scarf, we’ll try that method. The goal of a good scarf is a nice, even slope that will match the other piece of wood you intend to join. The more gradual the slope, the more contact area for a theoretically stronger joint. It’s recommended to have your scarf taper at at least an 8 to 1 ratio of wood thickness and sometimes even a 12 to 1. We use the 8 to 1 ratio and haven’t had any issues.
This is an example of an 8 to 1 ratio laid out on two ½” sheets of Hydrotek Meranti plywood we’ll be using for the bottom panel of the boat we’re working on now.
As mentioned previously, the Hand Plane method yields good result. Just use the plywood layers as a guide and keep everything nice and even. Once you’re just about to your mark, switch to a sander to help even things up.
All done. the layers are nice and even, and a little sanding with the block sander evened it out nice.
With the Hand Router Scarfing Sled from Woodhaven we’re now able to scarf all the sheets for one boat. Set up with an 8 to 1 ration and a 2 ½” Planer Bit the scarfing jig makes nice scarfs. There is still some cleanup work to be done with a sander, but it sure is a time saver.
So, there you have it. While we can achieve outstanding results using the Hand Plane or the Scarfing jig, we are anxiously awaiting our next scarf and using the Shaper Origin for a precise CNC Lap joint and smooth finish.
Keep checking back for more of our journey building our Drift Boat company.