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Lie-Nielsen Toolworks

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Gluing up the carcass of a project is a major project milestone in my mind. It marks the transition from preparing and milling stock to trimming and finishing. More importantly it gives me the first look at shape and size. I create my working drawings in 3D, which has many advantages, but one disadvantage over a mockup is that you are never really sure about the overall look until glue-up.

I Always Dry Fit Before A Glue Up Like most woodworkers I never glue-up a piece without first dry fitting it. This accomplishes a number of things. First it lets me know if I need to trim a joint for fit. Second, it gives me a chance to practice the steps I will use in the glue-up, which uncovers all the tools and aids I will need, saving me from hunting down something while glue is setting up. Lastly, and most importantly, it helps me develop a glue-up strategy and sequence. Without this dry run a merely stressful step becomes a disastrous and disheartening one.

While Inspecting The Dovetail Joints I Look For Proper SeatingMost of the joints in this carcass are dovetails. I like to inspect them for tightness and gaps. I also check to be sure they seat completely. Dovetails will almost always go together smoothly if the pencil marks that mark the transfer of the tails to the pins are still visible. This is a check that can be made before the dry fit but it never hurts to double check.

Dovetailed carcasses are unique in that, while clamps are useful, and sometimes necessary to seat all the joints, clamps can be immediately removed. The dovetails are enough to hold the carcass while the glue sets up. This allows for easy checking and correcting for square.

I Use Clamps To Seat The Joints But Remove Them For Dovetail Joinery Even with all this checking and dry fitting mistakes can still be made. After I glued up this carcass I noticed one. I have marked the outline where a hole is supposed to be in the picture at right below. This hole is intended to allow the pendulum and weight chains to drop from the clockworks compartment to the pendulum compartment. I should have milled this hole before glue-up. Fortunately, while more difficult, it is still doable after the glue sets overnight.

Oops! I Should Have Milled That Hole Before Glue Up Next I will mill the clockworks and pendulum compartment backs, sand the carcass and backs, and permanently install the lower back before moving on to the doors. Stay tuned for more updates on this project.

SketchUp Drawing Of Seatboard With Dimensions One of the more important components in a clock case is the seatboard. The seatboard is the board on which the clockworks is mounted and secured. Its placement determines the vertical and horizontal centering of the hour and minute shaft relative to the clock face. It also determines the clearance, or depth of the shaft relative to the clock face.

Drilling Large Chain Holes With Forstner BitThe seatboard consists of a number of holes that must be accurately placed. Two small holes are for threaded pins that secure the works to the seatboard. When installed in the clock the seatboard itself is fixed (no mechanism for adjustment). The positioning of the works on the seatboard directly affects all positioning mentioned in the previous paragraph. So these holes too must be accurate.

Roughing Out The Pendulum Rectangle With A Sabre Saw Since this is a chain driven clock there are four larger holes that allow the chains to move freely and hang in the pendulum cabinet (lower section of the clock). These holes need to be large enough to permit “pulling” the weights once a week for winding and to ensure no interference as the weights slowly drop while driving the clock.

Scrap Wood And Double Sided Sticky Tape Form A Template One rectangular hole is needed to allow the pendulum to pass through and swing. This hole does not require critical dimensions, simply enough room for clearance.

If you have been following this project on my blog, you know that the clock works for this project came with no documentation. I had to reverse engineer the seatboard design by taking very careful and difficult measurements of small, and deeply imbedded parts in the clockworks. I am sure you are asking yourself, “How can this be difficult? After all, there are only four holes we are talking about”. Well, let me assure you that positioning a 6” steel pocket rule inside the delicate works of a chain driven clock to make accurate measurements is all but impossible.

The Finished SeatboardI meticulously took measurements and used them to create shop drawings. After milling my first seatboard and mounting the works, I made further measurements to test whether alignment in the final clock would be correct. This resulted in changing the position of three out of six holes.

A Test Mount Of The Clockworks On The Seatboard I corrected the shop drawings, milled another seatboard and tested again. This time everything worked out perfectly.

Milling this component provided the first opportunity for me to use my new Supreme Drill Press Table purchase from Peachtree Woodworking Supply, Inc. It worked like a charm, allowing me to quickly, accurately and repeatedly drill the holes. For the larger holes I used a Forstner bit with a backing board to ensure no tear out of the opposite side.

The rectangular hole was a three step process. First I drilled two holes, near each end and inside the rectangle, and large enough to accommodate a sabre saw. Second, I used the sabre saw to rough out the rectangle. Lastly I used scrap wood pieces and double sided tape to form a a template for a template router bit to follow. The completed seatboard is shown above.

All Pieces Of Stock Are Marked For Orientation & Exposed Face My current project is a Tall Shaker Wall Clock. It is a gift for my daughter upon her graduation from law school. She graduated a year ago and this gift is a little late. But hey, I’m not getting paid to do this ya know! Anyway, I just stared by preparing stock for the sides, top and bottom. I cut all pieces to final overall dimensions including thickness. When building a carcass using hand cut dovetail joinery it is especially important that all mirrored pieces (right and left side for example) are precisely the same size and perfectly square. Next I carefully choose the surfaces I want exposed and then mark the material to be sure they go together correctly. Carpenter’s Crayon is perfect for this purpose.

My Tools Of Choice For Hand Cutting DovetailsA hand cut dovetail joint requires quality hand tools. Like all woodworkers who work with hand tools I have my favorites and will stack them up against anyone else’s favorites. It’s kind of a religious thing. My choices appear in the picture at left. The dovetail saw, chisel and dovetail marker are all Lie-Nielsen. The dovetail saw is the progressive pitch model; it has fine teeth in the front for easy starting and more aggressive teeth in the back for rapid cutting. The dovetail marker has a 7:1 pitch (or approximately 8 degrees) which I use for hardwoods, and also serves as a square to mark vertical line for half pins. The chisels are just the right length and well balanced. Their weight is on the light side so that your fingers do not tire after hours of dovetailing and unlike Japanese chisels whose triangular top edge cuts into your fingers, the flat top edge of the Lie-Nielsen does not.

The Dividers Are Set For The Width Of A Tail Plus A PinI like a light, hard rock maple wooden mallet. This one was recommended by and purchased from Nora Hall’s website. Nora Hall, if you don’t know, is an expert on carving. A small engineer’s square is ideal for marking the top edge with tail and half-pin spacing. I cut tails first and cutting perpendicular to the board face is critical for good fitting dovetails. The dividers are Groz with sharp points and are used to layout the pin and tail spacing by setting them to the width of one tail plus one pin and stepping the divider across the ends. Setting the dividers and marking other critical dimensions is accomplished with an accurate scale. I use the Incra Tiny T Rule which marks to 1/64″. The Lee Valley Veritas marking gauge makes quick and accurate work of scribing the pin and tail depth across the grain. And finally a well sharpened pencil with lead on the soft side for marking completes the tool set.

A Stool Comes In Handy To Provide Sufficient Elevation To Saw The Tails

The sides of this clock are 51″ long. Cutting tails on this length piece can be quite a challenge. In the past I would have used my adjustable height bench raised to its maximum height to secure the board to eliminate chatter while sawing. With my new Lie-Nielsen bench I find the face vice holds the piece securely and its size and mass all but eliminate chatter making tail sawing easy. I still needed to stand on something for elevation. One of the stools I wrote about crafting as Christmas gifts for our grandchildren came in handy for this purpose. I reposition it frequently so that my stance and arm are appropriately aligned to make the cuts. I use this stool again when removing the waste between the tails with the fret saw as shown at left.

There are two aspects of cutting tails that is critical to good joinery. The first I mentioned earlier is cutting perpendicular to the face of the board. Failing to do so will leave unsightly gaps, poor glue joints and weak mechanical joints. The second aspect is to stop the cut at the scribe line. Going past this point will show and leave a sloppy appearance, not one a craftsman wants to project.

There are a few aspects of tail cuts that are not critical. The angle of the cut is nominally 8 degrees from vertical, but this is not critical. Neither is the width of the gap (pin width). Machine cut dovetails would all be perfectly angled and spaced, but then they would look machine cut. The human is not a machine. Hand cut dovetails are beautiful precisely because they don’t look machine cut; they are all slightly different, adding to the beauty of the piece.

Trace The Pins From The Tail Board And Make Sure To Mark The Waste Area

The pins are a little more difficult. First, the pins are traced from the tails by laying the tail board on the pin board, aligning them perfectly perpendicular and at the correct depth and tracing the pins from the tails with a sharp pencil or knife. I prefer a pencil because I want to saw on the waste side of the pencil marks, that is, leaving the pencil mark which is actually part of the pin. This I can see clearly with pencil marks. However, a knife mark tends to draw the saw blade into its kerf leaving me less control. I complete the layout using the dovetail marker being sure to mark the waste area with Xs as shown at right.

Cut The Pins By Sawing On The Waste Side Leaving The Pencil Marks

There are critical aspects of pin cuts that must be adhered to. Cut on the waste side of the pencil mark, but aligned as closely to it, and along it as possible. Cut straight down using the vertical lines as a guide. Stop at the scribe line on both sides of the board. Paying close attention to these will assure snug fitting joinery – assuming you also cut the tails correctly. The trick to hand cut dovetails is being able to cut vertically and to follow a line. Once those two skills are mastered you can hand cut dovetails that go together the first time, every time.

It helps to cut vertically if your piece is mounted in the vice plumb. The shoulder vise on my Lie-Nielsen lets me quickly accomplish this by holding the piece flush against the vice as I tighten it.

The Majority Of The Waste Is Removed With A Fret Saw

After making all the vertical cuts I am ready to remove the waste. This is done in two steps. First, clear the majority of the waste from the pins by cutting it away with a fret (or coping) saw. I twist the blade in my fret saw to about forty five degrees with pliers. This allows the saws frame to clear the board as I cut. Turning it ninety degrees to the frame would make starting the cut near impossible. When sawing I try to stay as close as I dear to the scribe line leaving just enough to support the chisel cleanup that will follow. How much you leave depends on your experience and courage. If you are just starting out stay at least an eighth of an inch from the scribe line. Be sure you cut evenly front to back. You don’t want to cut close to the scribe line in front and below the scribe line in back. Judge this carefully. After a while it becomes natural and requires no special attention.

Cleanup Of The Waste Is Performed With A Sharp Chisel

The second step in clearing the waste is to clean up the material left by the fret saw. I perform this step with a very sharp chisel. Depending on how close I cut to the scribe line will determine how many cuts along the scribe line I will need to take. If you are doing this and you leave a quarter of an inch for example, you will want to make at least three passes as you approach the scribe line. The last pass should be no more than one eighth inch. Less is better. I hold the chisel slightly passed vertical such that the waste is cut angled into the board. The end grain serves no purpose in the joinery; only the faces of the pins and tails are used to form both the mechanical and glue joint. I check with a small engineer’s square that the material is removed such that the scribe line on each face is unimpeded by material that might project passed them.

The Pins And Tails That Join The Four Sides Of The Clock Carcass

The final joinery set is shown at right. Note that you can still see the pencil marks on the pins. As mentioned above they are part of the pin material since the tail was used as the mask to form the pins. Also note that the tails are cut perpendicular to the face of the tail board and the pins are cut straight down – that is vertical to the board. These pins will go together for the first time during glue-up with no dry fit required.

I have a confession to make. You can see that some of the end grain in the pin boards was chipped out. If my chisel were as sharp as it should have been this would not have happened. My chisel was sharp when I started out on the tail boards and I should have stopped to sharpen it for the pin boards. However it was close to dinner time and I was almost done so I plugged along. The small white sin here is that the end grain does not play a part in the joinery and will not be seen. So I can be forgiven, though it is not my usual practice. There, I feel so much better now that I got that off my chest.

If you are just starting out with hand cut dovetails, or haven’t yet started but would like to, I would highly recommend purchasing Rob Cosman’s series of video tutorials. I have been cutting hand dovetails for ten years now and consider myself experienced. But I still purchase nearly every tutorial I can to see how the masters do it so that I can learn and improve. Frank Klausz is probably the dovetail king with Rob Cosman a very close second, but Rob’s videos I find to be the best tutorials on the market. Don’t shy away from hand cut dovetails. Innate skill is not required. Anyone willing to practice sawing vertically and to a line can master them.

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