Template Routing
Template routing is a valuable skill that will take your routing skills to the next level. Using a template will allow you to create multiple identically shaped parts for a project with minimal effort. An accurate template that safely holds the work piece while routing is critical to successful template routing, so take the time to do it right. The parts created in this article will be used in a set of cedar Adirondack chairs. There are three stages in making and using the template to produce multiple parts: making the master template, making the working template and machining the parts.
Rough out the profile
Use a bandsaw or coping saw to rough the Master Template to shape.
Clean it up
Use hand and power tools to obtain an edge with the exact contour you’re looking for.
The master is the boss
Use the master template to mark the working template, then trim the working template to within 1/16" with the band saw.
Flush it up
With the master template secured in the working template a flush trim router bit does the fine work.
Easy marking
Use the working template to mark all the work pieces, then cut them on the bandsaw to rough shape.
A slight trim
The flush trim bit will shave the work pieces to final shape and size with ease.
Template
Laminate Flush Trim
Combination
Start with a Master Template
The master template will be used to determine the shape of the working template. It’s the foundation for the entire process, so make sure it’s the exact size and shape you need. It’s best to use a clear grained softwood like pine or cedar so the master template can be easily shaped to perfection.
I recommend you use a plan of the part, although you can free hand the shape of the master template if you like. Create a drawing or picture of the part required and glue it to a suitable piece of lumber, then cut the waste off, leaving about 1/32″ of the material on. Sand or use hand tools to create the exact shape you need and to smooth the surface of the template. If you’re cutting the profile without a plan, cut the edge to the shape required and smooth the edge. The curved edges do not need to be perfectly square to the face but should be close. The overall curve needs to be smooth and fair. Now the master template is ready to create the working template.
Produce the Working Template
When selecting material for the working template, it’s best to use a piece of ½” plywood. Plywood will provide a durable edge against which to run the router bit bearing. It also provides a stable surface with which to work. Be sure to leave enough extra material on the working template so you can attach cleats to it later. These cleats will position the work piece precisely on the working template and hold the work piece in place during machining.
To create the pattern, cut a suitable piece of plywood as shown and add cleats to locate the master as shown. A good grade of plywood is the best choice, although particle board or MDF will also work. Trace the shape of the master template to the working template and cut it on the bandsaw, leaving about 1/8″ for final shaping with a router. Using the master, either nailed or screwed to the template, route the working template using a bearing guided router bit to cut the template to the shape of the master template. Finally, check that the newly machined edge of the working template is smooth and ready to produce the work pieces.
Making the Finished Parts from the Working Template
Cut enough pieces of stock for all of the required parts; in this case, four arm brackets for two chairs. Make sure the machined surfaces are square and jointed as required. Using the template, trace the outline of the finished shape onto the work piece and use a bandsaw to rough it out. Be sure to leave ⅛” on the work piece. This extra material will be removed with a router and flush trim bit. Fasten a bandsawn workpiece to the template with brad nails, screws or clamps and cut the work piece to the finished size and shape. Be sure to avoid climb cutting while routing the work piece and be aware of where the flush trim bits at all times. The choice of fastening is dictated by exposure of the finished part; in this case, the tiny holes in the cedar will disappear during finishing. Clamps or double-sided tape will be required on some materials.
If you’ve never used a template for routing multiple parts, you will find this technique indispensable. Although I’ve demonstrated a simple way of using templates to produce identical pieces, there are a number of other, more complex ways of making multiple parts with router templates. Some parts need a slightly different approach to be made properly. It’s always smart to get comfortable with the basics before moving up to more advanced techniques.
Template Router Bits
There are three different types of router bits you can use for template routing. All are straight and have at least one bearing the exact same diameter as the cutter. “Template“ or “Pattern“ bits have the bearing between the cutter and the shank. “Laminate Flush Trim“ bits have the bearing near the end of the bit. The last type of bit is a combination of both these bits. They have two bearings and give you the ultimate in flexibility. See Issue #63 for a full description on the differences between these three router bits.