How to cut tight fitting Dovetail joints. (Recycled Jarrah Cabinet, Part 3).
The big recycled jarrah cabinet continues to take shape. The top sections of the cabinet will primarily be used for the housing and displaying of ceramic art pieces. The bottom sections of the cabinet will house some serious HIFI and media gear, plus as many LPs, CDs & amps; DVDs and as muchother technology as we can creatively fit within the space available.
I am currently working on the lower section of the cabinet. The longer section is quite deep, and the return is very shallow in depth. In this shallow section, behind the pair of doors, will be two storage bins for good old-fashioned vinyls - LP Records. In an effort to maximise the space available, I have been making another pair of bins to hold as many audio CDs as possible. The space left over will be divided into small shelves to hold more CDs. The bins will be hinged to fold outward in order to access their contents, and these bins will be held together by dovetail joints, with Half-blind Dovetails at the front and Through Dovetails at the back.
Marking out and cutting the dovetail joints.
With the sides, ends and faces of the boxes a consistent thickness, marking out the Through dovetail joints requires the use of only one marking gauge setting - approx 1.0mm wider than the thickness of the material. This leaves a tiny bit to clean off after the glue has dried. I am one of those "tails first" woodworkers.
Marking out the Half-blind dovetail joints, two marking gauge settings are required. One will be as above, about 1.0mm wider than the thickness of the material. The other will be the length of the tails - in this case 3.0mm less than the material thickness of 14mm. These tails will be 11mm long.
The tails are always cut in the sides of drawers and containers. With use of marking gauge, sliding bevel, rule and marking knife, the tails are marked out. In this case, there is a difference in the marking out on each side piece, as the front joints will be half-blind dovetails and the back joints will be through dovetails. Regardless, all the tails are cut first. When doing the marking out, the only pencil lines needed are on the ends and one one face. Note on the pic below that the pencil lines off the sliding bevel are marking the tails deliberately longer than required, extending well below the scribe line which marks the base line of the tails. These long pencil lines make it easier to make sure the saw follows the correct angle. No lines re needed on the other side of the piece. The bevel was set at 1:6.
| A side piece held in the vice ready to do the first set of cuts. |
| A nice little dovetail saw makes the cuts with ease and makes a very tiny kerf. |
| Main cuts for the tails completed, down to the scribed base line. |
| Use a coping saw to remove the waste down close to the scribed base line. |
| Sneak up to the base line with the chisel. The last vertical cut is done with the chisel sitting right in the scribe line. |
| All tails cut and ready for the next stage - to transfer the lines over to mark and cut the pins. |
| Transferring the tails to mark the pin positions - half blind dovetails. |
| Extending the pin marking lines downwards to assist accurate cutting. |
| Cutting the pins for the half-blind dovetails means cutting down to the two base lines. |
| First stage of the waste removal, sneaking up until you can chop right on the scribed base line. |
| Second stage: Waste between the pins best removed with the piece held vertically with support behind. |
| Sneaking up on the other scribe line of the half-blind dovetail joints. |
| Job done. Waste removed between the pins for the Half-blind dovetail joints. |
| The moment of truth! Hammering the two components together for the first time. |
| Not bad. You can see where a small amount of paring to the top shoulder, to the tail base line, will bring a tight fit on the end of the adjacent tail end. |
| Line up the tail base line with the inner face of the other piece, and mark the pin positions with a marking knife. |
| Marking knife marks show pin positions for the Through dovetail joints. |
| Extend the lines down and cut the pins, on the waste side of the lines. |
| Using a coping saw to remove most of the waste between the pins. |
| Most of the waste removed, ready for the chisels to do their work. |
| Waste chopped out. Torn out fibres are not unusual where the chopping meets from each side. |
| Another moment of truth. Hammering the joint together for the test fit. |
| Nice fit! No paring or trimming required. Tight, clean and accurate. Yippee! |
| Prepare purpose built clamping blocks will help pull up the joint during gluing. |
| There's nothing like a bit of squeeze-out from nice tight-fitting joints. Beaudy. |
With vertical space within the cabinet at a premium, I opted to fit the bases in a way that took up the least amount of space. I rebated the base of each box after assembly, with a router, cleaning out and squaring the corners with a sharp chisel. Ply bottoms 1/4" thick were glued and screwed into the bottoms of the 4 boxes.
Fitting the storage bins into the cabinet.
The storage bins for vinyl LP records, the storage bins for CDs and the little CD shelves taking up the remaining space, will all be housed behind a pair of doors.
The two LP bins I have opted to hinge from the front, using "Florentine Bronze" flavoured piano hinge. I only needed just under 900mm (3 ft) of it, but had to buy in in a 3.6m (12 ft) length. The other option was to buy it in a 35m (115 ft ) roll!! ...I settled for a 12 foot length. To prevent the bins from emptying their contents onto the floor, a stop was fitted for each bin.
Fitting the CD bins above these was tricky, due to the limited space. After some planning and experimentation, I have fitted sliding pins which I made specifically for the purpose.
| LP bins and CD Bins will be behind doors. The plinth is sitting on top of the cabinet. |
| One of the two CD bins in the dropped-down open position. |
| One of the four pins I made from a piece of M10 threaded rod. |
| One of the two LP bins in open position. It's hinged on piano hinge at the bottom. |
The whole cabinet will be sitting on a 4" (100mm) plinth. When making up the plinth, I opted to do half-blind dovetails on the two external corners. Not what I would normally do, it looks pretty good I reckon. I have seen it before in some antiques furniture, and given this cabinet is being made to fit in alongside other antiques, it is a small detail which will work well - if anybody notices!
| Gluing up the plinth. You can never have too many cramps - or straightedges... |
| One of two dovetailed corners on the plinth. |
There is a lot written and said about dovetail joints. These days we give them an importance and mystique which would have seemed very strange in days gone by. In the past these joints were just a practical way of creating a strong joint between two pieces of wood at right angles to each other, without the use of metal fixings. That's just what I did for the joints in the plinth, really. It is also a good way to build strong corners in the 4 bins/boxes referred to in this post.
Sure, you can make pretty flash dovetail joints with screaming routers, fancy jigs, and all that. For me, though, the real satisfaction comes from confidently making these joints by hand - and using no filler. It's just good honest old-fashioned hand tool woodworking. Sensual and satisfying.
The other thing I really enjoy is feeling a sense of connection to past generations of craftspeople who have come before me. In fact, that beautiful little dovetail saw I used has the name of a previous owner stamped in the handle. His perspiration and mine mingle in the patina of the handle. I wonder what he made all those years ago as he toiled at his bench with that saw. I share in the legacy of those who came before me. I am but a custodian, of both tools and knowledge - but also of the simple joy to be found working wood by hand. As a custodian, I also have a responsability to pass all this richness to the coming generations of woodworkers. My hope is that you found the info in this story helpful.
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