The Deep Through Mortise

Ordinarily, a through mortise can be routed using the approach described above. But every once in a while, the demands of a mortise go beyond the reach of even the longest of router bits.Thc right template setup can extend rour router's reach.

An example is a knockdown sawbuck tabic I made a couple of years ago.'ITic underpinnings were two sawbuck leg assemblies joined by a stretcher. Each pair of legs was joined in a crosslap.A tenon on the stretcher passed through a mortise in the legs and was locked in place with a removable wedge or key. as shown in the drawing Sawbuck Leg Assembly. Since the legs were 2-V» inches thick, the through mortise was beyond the reach of my longest bit.

By fitting the template with identical positioning blocks on both faces. I was able to do the mortise. The hidden problem here is alignment. If. in shifting the template from one face of the work to the other, you turn over the work or you turn over the template, the template likely wfl he misaligned. What you have to do is move the tem-phte just as though it was a playing card you were moving frum the top of the deck to the bottom. After you have moved and reclamped the template, turn the whole works over so you can continue routing.

I made the mortising template as shown in the drawing Sawbuck U>g Mortising Template. I laid out and cut the window in the center of the template stock—a piece of V* inch birch plywood. The mortise window was scaled to wort: with a '/>inch bit/Vinch guide bushing combination.

When the template was ready. 1 laid out the mortise on ooe leg assembly. Next I cut two triangular positioning blocks to fit into the crotch of the legs, tight against Ixnh legs. Now I was ready. I centered the template over the


Routing a deep through mortise calls for a mortising template with positioning blocks on both faces. The two blocks allow you to reference the same edges of the workpiece for position when moving the template from one face of the assembly to the other. Here I have routed as deep as I can into a nearly 3-inch-thick ieg assembly. The template design allows me to move it underneath the assembly, keeping its orientation essentially unchanged. Then I can turn the whole works over and rout from the second side to complete the mortise.

layout and clamped it to the leg assembly. 1 next fit a positioning block firmly against the legs, then drove screws through the template into this block. I turned the template over and attached the second bl<x:k, very carefully aligning it with the first positioning block. Then I trimmed the tips off the blocks to provide clearance for the router.

With the plunge router fitted with the appropriate bit and guide, I started routing the mortise. After cutting approximately halfway through the assembly, I undamped the template, shifted it to the other side of the assembly, nirncd the leg assembly and template over, and reclamped the template. Finally. I completed the mortise.

Tills approach won't work for every extremely deep mortise you must rout. The project must present a couple of reference edges that will enable you to switch the template from one face to the other and maintain proper alignment. And if it does, this approach may save your day.

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Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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  • katie-leigh
    How deep can router go?
    9 years ago
  • Neive
    How do you router a mortise with a template bit ?
    9 years ago

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