After a long hiatus, I came back to this project, picking right up to clean the tenons and then cutting the double-shoulder tenons for the single bottom rail. From there, on to lay out for the stand. In order to be level, the mortises have to line up precisely with their opposite numbers, and the top pair have to be perfectly in line. Fortunately, Roy's article is quite detailed here in setting out a lay out method. I spent more time than I normally do carefully setting down lines, then marking them. From there, it was time to start the mortises.
In doing so, I realized I have made my first significant mistake, and a minor one. I have learned several times over that when doing a mortise and tenon joint, one's life is far simple if you size against the chisel you are going to use. Forgetting to do that was the minor mistake. Checking what to do instead revealed the significant one - I have somehow undersized the tenons for the bottom rail, they are not 1" thick but around 3/4". I may live to regret it, but I am going to adjust to use what I have.
The through mortises are somewhat scary, even though I used the same gauge to layout each face it won't take much to make a mess of one side or the other. There is an inconvenient knot on one of them, so I am going to start with the other. Following the instructions, I trench one face, using a chisel to define the edges and then a series of chisel cuts to remove about 1/4" deep. Then I flip over the board and hope for the best.
The photo shows the series of cuts to develop the trench. Some authors seem to prefer to use just a chisel to clear out a mortise, but Roy's article calls for an auger in a brace. I am going to stray from his instructions just a little, because I don't have quite the same confidence in using a brace - I will use a 13/16" bit, even if that means I have a little more clean up work.
Despite the fact that these bits have not been sharpened properly for probably at least forty years (a subject of a future post...), the auger makes short work of the spruce. I drill to roughly halfway from one face, then flip the board over. The board is upright in the bench vise, on a foot rest for support so the boring is at a comfortable height.
The next mortise is going to be interesting - the knot is outside the area of the mortise on one face, but half inside on the other. That will be next session.
Somehow the edges of this face are better defined down to 1/4", but I have more material to clean out. The good news is the two holes are meeting. It will take a little while to clean up with chisels, and I think I will be a little braver for the next one and use a larger bit.
As a result of not using a chisel to size the tenons, I have had to use a gauge to define the mortise. It is just a shade smaller than my 26mm Narex chisel. so I have to use my 20mm, effectively doubling the number of cuts. For cleaning up the sides, I used the 40mm, and for finishing off the mortise I used a 1/2" mortise chisel to do the hard work. But I pleased with the result. The two faces lined up, the inside surfaces are fairly smooth. I will need to clean them up a little, but there are only a couple of minor blemishes to the show faces which I can probably clean up if they bother me.
Next session I will start on the adjacent mortise, and if time permits on to the mortise for the bottom rail.
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