How to Cut a Timber Frame Mortise & Tenon – Part 1

We use a variety of tools to see what works best for cutting Mortise & Tenon joint into some old timber beams.

I have been working on a building a new base for an old pool table to put in our basement. The table was picked up for free because the original base had been ruined. We decided to cut some timber frame beams and build a new base for it with Mortise & Tenon joints.

Step 1 – Measure & Mark the Tenon

Start by measuring and marking a line all the way around the beam for how long you want the Tenon to be. This will become the shoulder where the tenon starts.

Next, get a good measurement of both the height and width dimension on the end of the beam where you want the tenon to be.

Decide what you want your final tenon dimensions to be. Then for each dimension, subtract the tenon size from the beam measurement. this will tell us how much material we will need to remove from the beam. We then divide this by two in order to know how much we remove on each side of the tenon.

Using the measurements from the last step, mark the shoulder line on the beam at those points. Then using a square, use these points to draw cut lines on every face of the tenon. Also transfer these lines down across then end face of the timber.

When finished, you should have an outline of the Tenon, on the end face, and cutting guide lines on all 4 sides of the beam.

Step 2 – Cut the Tenon

In the video we experiment with several tools to see what works best for cutting the tenon. We start with the traditional hand tools that were used for constructing these joints in old timber frame barns and buildings. These include, hand saws, bow saws, chisels, and hatchets.

Then we move to using more modern power tools, to include a chainsaw, Skil Saw (circular saw), and a bandsaw. Any of these tools can do the job, but we compare the results and effort needed with each tool in the video.

Amazon links for the tools I used in this video: (Affiliate links)

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