Round Leg Dowelling Jig
Fixing round legs to an item can really enhance its looks, especially if the legs penetrate the edges of the top as they do in the chopping board and small desk I made earlier. To attach them securely, dowels are great, but you'll need to be spot-on when drilling for them. Two simple jigs will help you do this.
I'll be describing how to make and use the two jigs that I used to join the legs to the cutting board and small desk you can see in the photo's.
Supplies
Hardwood, such as maple or beech will be ideal, and should last a few projects (If you have the facilities, then steel would be longer lasting).
The Jigs
The two jigs are shown in the photo, and are made as follows:
Leg Jig
Bore a hole through a thick block of hardwood, the diameter of the round legs to be used.
Bore two through holes perpendicular to the leg hole, one either side, and sized to take the steel rod.
Next to the rod holes, bore two clearance holes for screws halfway through the block, and then swap to a pilot bit to continue the holes. Size the clearance holes and pilot holes to two large wood screws.
Saw the block in half, perpendicular to the rod and screw holes, opening the leg hole in its length.
Cut two pieces of steel rod just longer than the block. These will act as alignment rods.
Put the two halves together and press the rods into their holes.
Install two wood screws, and draw the two together. Now slacken off enough so that a leg can be inserted.
Non-Leg Jig (The jig for whatever you wish to join the leg to)
Turn a length of hardwood into a cylinder with a square head. The diameter should match that of the legs and the bit used to cut the open socket for the leg.
Completing both Jigs
Install the non-leg jig into the leg jig, and tighten up the screws.
Using the same bit you intend to make the dowel holes with, bore two (or more) holes through the two jigs, so that they pass across the centre of the leg hole. A drill press is ideal for this, but they can be bored freehand with care.
Your jigs are now complete!
The top of the leg jig, and the underside of the square head of the non-leg jig, are the reference planes for aligning the dowel holes, so you may wish to make a few large washers to help off-set the dowel holes, if you wish to have the legs proud of, or just below, the top of the item you're attaching them to.
Using
Hole for the leg & dowel holes
Bore the half circle socket into the item. It can be less than half a circle, but not more, as the leg needs to be inserted from the side. The photo is of me boring the socket in the cutting board.
Add the dowel holes using the jig, clamped in place and aligned so that the dowel holes lay in the centre of the socket. You can see that I used the square head to orient the jig.
Install the dowels.
You can also see me making the dowel holes for the small desk in the other photo.
Leg Dowel Holes
Insert the legs, one at a time, into the leg jig, and bore the dowel holes, using the jig holes as a guide for the bit.
If the legs aren't symmetrical, such as those on my small desk which are octagonal and tapered on two sides, then align them appropriately in the jig before clamping with the screws.
Example
You can see the chopping board being made using the jigs in the video.
Thanks for reading the instructable