|Forum topic by Randy Woodworker||posted 09-09-2015 02:00 PM||697 views||1 time favorited||8 replies|
09-09-2015 02:00 PM
Here’s how I make half-blind DT’s without a jig. It is based on a 3/4” thick drawer front and 1/2” thick drawer side. This method can be modified to suit any configuration you want.
It starts with a template made from 1/4” plywood as shown. The depth of the template openings are fine tuned to accommodate the 1/2” tail board thickness exactly when the template fingers are clamped flush with the sides of the pin board.
For this method to work, the thickness of the plywood template must be the same thickness as the amount of material left below the pin socket. The reason for this will be evident later on.
The template is clamped to the underside of the pin board.
A router with guide bushing and dovetail bit is required. There is no real requirement for any particular size or type of bushing or bit. You just cut the template taking these various dimensions into account.
The pin sockets are then routed.
Now we use the pin sockets to mark the tail board.
To get consistent alignment I made a simple jig that serves two purposes in this process. The first is to help align the pin and tail boards for making the tails.
The spacer is made from the same material as the pin template and offsets the tail board exactly the right amount for marking the tails.
I then use a marking gauge to scribe along the bottom of the tails on both sides of the tail board. This gives a good registration mark for chisel placement when trimming later on. This scribe line must be precise.
After that I cut the lines for the tails on the bandsaw being careful to cut on the waste side of the lines.
I then use the other side of my little jig to back cut the tails at the same angle as the pins. The amount that the 1/4” plywood protrudes over the tail board thickness is fine tuned so that the router bit barely touches the top of the tails. Once again the plywood on the jig is the same material as the template used to route the pin sockets. Keeping all the offsets the same thickness as the template material means all router cuts can be done with the same bit extension. No router adjustments necessary after initial setup.
Then I finish the cuts on the bandsaw.
Some trimming with a chisel and I knock off the back corners to fit the sockets.
Not a bad fit.
I have made better ones, like shown here.
This method requires some skill with hand tools, but uses power tools to take some of the hardest work out of it and provide some consistency. The templates are made from scraps and you can make as many as you need for any situation. Not the best if you need to crank out twenty drawers for a kitchen or bedroom set and you are on a schedule (get a good jig for that) but it is an economical and practical method for a few onesies and twosies.