Monday Woodworking 101 - Hand Cutting Half Blind Dovetails
In this 101 I'm going to detail how I hand cut half-blind dovetails. A half blind dovetail means the joint is only visible on one corner. This is used primarily in drawer fronts or when there is a groove that needs to be hidden.
This was a learning experience for me as well. I have not cut many half-blind dovetails, and when I did, they were just to practice sawing or layout. These are "honest" pictures. There are some little imperfections, but with a little glue and sawdust, these joints would look perfect.
The joint is dead square and the sides are square - that's the important thing here
I've got a piece of walnut and a piece of cherry that I ripped to the same size. The walnut is roughly 1 1/8" thick and the cherry is about 3/8" thick.
Bonus tip - this is why I generally cut around knots. This knot has so much tension that the board just continues to bow even after jointing.
Not a lot - and I could have gotten away with even less. Dovetails do not require a lot of tools. Having two marking gauges is very helpful.
It's really important the edges are square, so I take them to the shooting board after cross cutting. Details on the shooting board here
I milled this piece of scrap to about 1/4". I am using this to layout the line for the half blind pins. You will see way I do this in later steps
I set my gauge to the pencil line and reinforce it and make it permenant
I then use that gauge to mark the baseline for my tails on the cherry - all 4 sides
I take the second gauge and set the pin to the thickness of the tail board
and transfer that to the face of my pin board. The outside face only
I then layout my dovetails. I used my typical 14 degree maker and uniform spacing. I walked out the tail locations with a compass. I then cut the tails and remove the waste as detailed in this project
To remove the waste from the edges (where the half-pins will go) I first make a ledge for the saw to ride against with a sharp wide chisel
Then carefully saw right up to the baseline
Once complete, I reinforce my gauge line with a knife only on the portions I am removing
I start paring the waste from the front and work my way toward the baseline. This prevents the chisel's tendency to act as a wedge and push back the baseline - causing gaps
Once at the baseline, I chisel half way
Then flip to finish it
Sharp chisels make all the difference. I strop my chisels before getting started and keep stropping them often
Now time to transfer the alignment. I have an alignment board in the vise that helps support the work.
During this step, I line up the baseline of the tail board (cherry) to the edge of the pin board (walnut), and make sure the edges of the boards line up.
I use a marking knife to transfer the tails to the walnut pin board
I use my dovetail marker to transfer the vertical lines down the face of the pin board
And I mark the waste
My usual dovetail mantra is "sawn not carved". However this joint is carved. The sawing portion is not even necessary but chiseling would be really difficult without it. Try to stay well inside the waste here
Cut just to the inside of the waste on an angle. I try not to go over either line. I broke one of my own rules here and I used a saw I don't normally use. It actually worked really well, but I did overshoot my baselines
Now for the carving. I have the piece in a bench hook ready to remove the waste with a chisel. You can really see where I overshot my baselines. If this were an actual piece and not practice, I would have scrapped it.
Like with the tails in the cherry, I reinforced my gauge line with a knife. I chisel into the knife line to remove a bit of material
Then chop straight down a bit
Then I chop into the end grain
The result is this. Chips ready to pry out. I proceed until I get close to the baseline, then move onto the next. Chop down vertically, then chop into the end grain
Be careful when removing the chips. As you can see there, they are the same shape as the dovetail. Levering them out will cause bruising. push them out from the back
Done with the rough removal. Ugly, I know, but I'm away from all my lines and can clean it up now
Remember that scrap I used to layout the baseline? Well this is why I used it. It provides a guide for my chisel. I place the chisel on the scrap piece and pare straight into the socket. Perfectly square and even baselines this way
I learned another trick recently too - the router plane
Used this on the last pin. I like this method a lot and would recommend it if you have a router plane and either a spearpoint cutter or a very narrow one as shown here
Now to clean up the mess on the inside. When sawing on an angle, the saw doesn't get inside the corner. I carefully pare this away with a chisel
I also make sure the sockets are square
All cleaned up. I did use a set of skew chisels after this to get into the corner. I would definitely recommend a pair for anyone who does a lot of half blind dovetails.
Good fit! I am pretty happy with this. The pins are just slightly proud, but everything is snug and square
After planing it looks good. There are some gaps where I bruised the walnut a bit with the chisel, but once glued together and sanded while the glue is wet, they would become unnoticeable.