Many mortises are made with a router which creates rounded ends. Tenons cut using power equipment and/or hand saws create squared ends. The options are to square up the mortises with a chisel or round over the tenons using rasp and chisel. Or buy yourself a Festool Domino. The last option is not for me. So, which option do I choose?
Depends. Mostly on the mood as I find each approach takes about the same amount of effort, skill and time. I use either approach without pondering the implications…until my latest build, a book cabinet.
The doors have rather unusual joinery (or more like unusual combinations) which make sequencing for glue up significant. Note the sliding dovetail lower right of this door. Fun.
With all this asymmetry and my own humanity, the joints closed up nicely and it looked pretty good … BUT … things were not quite perpendicular where I wished them to be. I was shocked at how many of the joints needed tweaking. Fix one joint and it impacts another.
Being a woodworker who has had to “fix” a mortise and tenon joint before this was not a big deal. But, wait, square mortise and tenons allow you to cut/patch either the mortise or the tenon without too much creativity. Altering rounded mortises and tenons, as I used this time, are not so straightforward.
So when you know you going to mess up, perhaps square joinery has an advantage over rounded. This discovery may not alter my future decisions, but the next time I am bitten by the need to alter a rounded M&T joint, I shall think of this blog post, shake my head and go have a drink.
In the two part half-blind demo post, I created the sockets entirely with the chisels. However, I will often use a back saw to define the edges of the sockets. Because this is not a through cut, you will only go down roughly half way. When dealing with tough stock such as bubinga or the highly-figured mahogany shown here, I will also scoop out part of the material using my bowsaw. That saves a bit of wear and tear on the chisel edges and the aging operator’s joints.
Note: In the next post I show a few additional steps commonly used when creating the sockets. See extra.
I now prepare the sockets in the pin board which typically is a drawer front or case top and bottoms. I alternate vertical cuts with horizontal cuts to pop out waste, staying away from marks until the bulk of the waste is removed. The outside half pins can be quite fragile so it is good to reinforce them with clamps [see photos].
Some people will use a trim router for this task. That helps give uniform floor for the socket. Another approach is to use a Forstner bit in the drill press to achieve the same result. I am attracted to using the chisel approach. One drawback is the possibility of the horizontal chisel cuts diving downwards following grain direction. I try to be careful and save the final “horizontal” cuts for when I place the board vertically in my Moxon vise.
After the bulk of socket waste is removed, I chop down the knife line. Then placing the board in the Moxon vise I make the half-blind cuts and make other refinements which are easier to see in this orientation.
I test the fit further refinement as necessary. I leave the clamp in place for the fitting if possible.
This demo was made with two test boards. At a later date I’ll post some pix of this same procedure with a real project. I am currently working on a book cabinet which has a nice drawer. Stay tuned.
A visitor to my shop was asking about techniques to create half-blind dovetails so I took photos of the step-by-step. There are many ways to achieve that joint. This is just one approach.
A shallow (<1/16 inch) rabbet is cut at router table. The push rig allows safe handling and to keep a narrow workpiece perpendicular to the fence. An extra waste board is used here because the rig is pretty well chewed up. The pin board is then placed tightly against the rabbet and length of tail marked with knife. After marking the side opposite the rabbet with marking gauge, the tails are drawn with a shop-made template. Usually I use a bevel gauge for this. The template used in the photo is 14 degrees, which is greater than typically used for drawer construction.
A backsaw cuts along those lines down to the knifed line. With the board in the Moxon vise, a chisel creates a small notch to guide the backsaw. The bowsaw with thin blade is used to remove interior waste, staying away from the knife marks. Chisel to the marks and place the tailboard against the pin board for marking with a knife.
Pencil marks indicate material to be removed. With larger projects it is easy to become confused so I am in the habit of using a large X to indicate waste.