Saturday, December 30, 2006

Night stand - parts and pieces (post five)

I cut a lot of various parts today and used mortise and tenons joints, but you've seen that so I'll skip the boring details. However, I did stray from traditional joinery this afternoon so I'll introduce that technique.

The furniture I'm patterning my design from both have an "under-top". It isn't a full piece of wood like the top is; it is just a frame that appears to be a base for the top. I milled the pieces for this "skirt". It is pictured to the right. This goes just under the top surface of the night stand, but it is slightly smaller.

Wood can be glued edge to edge and "top" to "top", but it can not be glued on the end grain so I have to fasten the pieces together using some mechanical method. More on that later, but now notice the groove or dado on the inside. I will use this dado to attach the top allowing for the top to move. I will show this when I get to it, but for now remember the groove.

A biscuit is a handy European invention that is now widely used to fasten this kind of butt joint. You can see it to the left along with the biscuits. These are small pressed pieces of wood in the shape of football. They come in various sizes for different applications. I am using the largest size. The idea is simple - a small blade cuts half-a football shaped groove in the end of the wood. Insert the biscuit and join a matching piece of wood; cut the same way in just the right spot, both up and down and left to right, to the first piece of wood. The biscuits expand, the glue drys and you have a very strong and simple joint.



Here is a biscuit in a joint. You can also see where I stopped the dado so as to not interfere with the butt joint. I wasn't precise with this cut and just make a rough mark. By the way, this dado is done on the table saw with a very wide blade that is adjustable in width. It is called a dado stack. I could have also accomplished it with a router, but it is harder to set up - the table saw is quick and easy.




























Here is the assembled piece. I will glue this overnight and use a router tomorrow to profile the edge. This actually is the first piece I have glued. I still am not going to assemble the entire stand,but I will start with some of the parts - I have to - there are almost 50 pieces stacked and taking up room!


















I also glued up some panels for the bottom, or "floor" of the stand. These boards are simply glued together on each edge after being joined on the joiner. A glued joint like this will crack and split the wood before it will break. This is in contrast to the end grain I just wrote about.


The Snow Storm

Well, here's the final damage. It may be hard to get an idea of exactly how deep. The largest piles are just slightly taller than I am. On the level the snow is just about waist high. We were spared from the last final one to two foot. The forecasters were calling for a second storm followed closely on the heals of the first. I'm not sure what happened, but it never materialized.


Friday, December 29, 2006

Night stand - the carcass comes together (post four)


The next items to make are the stretchers for the front. These separate the two drawers and the area with the doors. In modern furniture it is typical to have one at the top too, but the Victorian pieces have no top stretcher so I will not use one either. Mortises are first cut into each leg. This is accomplished on, of all things, a mortiser. Basically, this is a drill that cuts a square hold. Set-up takes a while, but once you get it going the holes go quickly. The depth of each mortise should be slightly deeper than the tenon. If you call it too close the shoulder won't sit tight against other member. This also leaves a small space of the extra glue that will be pushed in at assembly.






























Once the square mortises are cut they are then cleaned with a sharp chisel in preparation to receive the tenons. Next, I mill up the stretchers and cut the tenons on each end. The bottom stretcher is larger as a design element. This gives the base a sturdy feel and supports the wood on the bottom.
Although, it may look like I use only machines every piece get tuned by some quick hand work. These pictures show trimming the tenon so that it is just the right size and flushing the shoulder so it sets perfectly flush. I set the plane blade to remove .002 with each pass. Obviously, it is better to make the parts slightly oversize and then fit them. It is kind of hard to add once cut!






































WOOPS! I'm always ripping myself up with the hand tools!

















Now to check it out. This is the basic carcass hastily assembled without glue. That will be later.



Night stand - the start (post three)

THE WOOD

It took about an hour to select the wood. You might imagine picking boards off of a pile, but it isn't that simple. Wood, when cut, tends to bend and twist if it isn't carefully selected, so I'm looking at the grain for many characteristics so the table doesn't tie itself in knots when complete. It is advantageous to select boards from one tree, but I don't have that luxury so I have to look at color and grain too. All kinds of different grain will look odd and tend to break-up the overall look calling attention to each individual piece of wood.


Here's the stack. It doesn't look like much - yet. Now, I have to go through and mark each cut so as to plan the use of the wood effectively. Again, I want the the quartersawn pieces in certain places and certain grain in other pieces.

THE CUTTING

I am using 1/2, 3/4, 1, and 1-1/2 inch pieces. Each piece will be milled to thickness using a planner, then joined on one edge so as to have one straight edge to begin ripping on the tablesaw. This process actually takes a quite a bit of time. Once complete I start cutting the individual parts. This is a few of the parts for each of the side where I will start. Next, I start milling the tenons on the parts that need them.













The requires a lot of work on the tablesaw. First I set-up a machine that holds the wood so I can mill the cheeks of each tenon. You can see the first two cuts on the end of the one of the side pieces. Two more cuts complete this operation. Each tenon must be very precise so the glue is not squeezed out, or the fit too loose. It is common to work at tolerances of .01.


















Next, I cut the shoulder of the tenons. As you can see the tenons are smaller than both the width and depth of each piece. This makes for a clean look when assembled. If the mortise was cut to the full size of the board a ragged edge would show and it would be difficult to control the width when clamping.



















Next a grove gets milled in each leg to accept the tenon and the 1/2 inch panels that go between each rail. This picture show some of the pieces after finishing this phase.


















The next picture shows the end of an assembled panel. I won't glue this until much later - it is just stuck together for now. Look closely and you can see that each thin panel (1/2 inch) can move in the space between each rail. Also you can see the tenons of each rail even with the panels which will fit into a groove on each leg.


















I then mill a grove in the legs to accept the rails and panels. The first parts, the sides, are now complete. This is how the sides will look - two on each stand. I still have work to do to the legs, but the side panels (after final fitting by hand) are ready to assemble. The back of each stand is made the same way, with poplar though. Poplar is cheaper and backs won't show and poplar was customarily used in this period. In cabinetry, this is called a secondary wood.

Thursday, December 28, 2006

Night stand - wood movement, joinery (post two)


When assembling anything out of solid wood (vs. plywood) one has to consider wood movement. Wood will move - it cannot be stopped. And, if it is held tightly it will crack, split, push, and otherwise create havoc. So, either design it to move, or watch it slowly tear it self apart. As I said, wood is anisotropic - it moves in different directions depending on grain direction and it moves with changes in humidity.

A board has three dimensions - length, width, and depth. But, grain direction is dependent on how a board is sawn. Wood moves least in length, and for practical purposes the amount is insignificant and in furniture construction almost ignored. It moves least tagentently to the grain - as in the quartered board in the diagram. This is called quartersawn or rift sawn lumber. It move most in the flat sawn dimension, or as woodworkers say, "across the grain". (It also tends to cup because of the differences in expansion and skrinkage - the two opposing forces working in opposite directions.)

So, what does this mean for our night stand? It must be designed for the movement of the wood. The best way to illustrate this is to look or think about a door panel. Most likely there is one in your kitchen. A typical door has rails (on the top and bottom) and stiles on the sides that frame the panel. The panel is not fixed, but floats within the four sides. This is called frame and panel construction or a floating panel. If the panel were fixed the panel would crack (during low humidity) or push apart the stiles (during high humidity).
There are many ways to accommodate wood movement and the selected method is a factor of many considerations. I will use the floating panel on the sides, but the panel won't be raised, but flat fit into a grove along the legs and the intermediate horizontal sections. Each panel will fit loosely and thus not push upon the other panels.

In addition to the wood's movement there is joint strength to consider. Wood can be joined from anything like a simple screw or dowel to dovetails and tenons and everything in between. As with most things, the most difficult is most often the best. That is why modern furniture is seldom made with traditional methods (or traditional materials like solid wood - plywoods and particle board can't even be joined by traditional methods.)

Most of the wood joints in these two stands will be mortise and tenon. Basically, a tongue is formed on one board and then fit into a square hole in the adjoining board. Usually, one piece is fit perpendicular to the other similar the the diagram of the rails and stiles above.

After basic design I need to write down the size of every piece of wood and how many I will need and then go to the lumber yard and try to find the sizes I need. This process is very much like a big puzzle - there are somewhere around 100 pieces of various sizes and thicknesses which will be sawn from various size boards. The object is not to have too much waste. Oak is about $4.00 a board foot and waste gets expensive fast. (a board foot is a piece of wood 12 inches wide, 12 inches long, and 1 inch thick).

To the lumber yard.

Night stand - design (post one)

One of the problems with an antique country Victorian bedroom set is that there simply aren't any night stands of the era - let alone something that might match what we have. We have used various stands beside the bed, but nothing looked very good, and we usually only had one so one person had the light and the clock. Now, we have a king size bed that is so tall it takes a running leap just to get in bed and everything is now too short. So, I'm going to make two matching night stands and I thought some of you might be interested in the process. I will start with the design, discuss the joinery, show the construction, assembly, and finishing. I will finish with a picture of Tammi, freshly torn from slumber, frantically beating the alarm clock against the top.

I am going to match these...









































Both are oak and although similar, not exactly alike and not a set; therefore, the design elements will have to be taken from both pieces. Of course, as I said, the Victorians didn't really have night stands. I guess the fact that they didn't have alarm clocks and lamps may have something to do with that. So, whatever I come up with won't really have existed in the period, but hopefully you won't be able to tell. After several rough sketches I began in CAD and I ended up with this drawing.


(I don't know if you'll be able to see this - try clicking on it to open it up full size) This drawing shows the basic design without the joinery. I used the principle of the golden rectangle to come up with the overall dimensions and the entire front is divided into roughly thirds. The proportions are very important to the success of the design. Two drawers are at the top- the smaller one is on the top with the larger one below. Drawers generally get bigger as they go down. Two large "posts" frame the piece - each 11/2 inch square. Most of the rest of the elements are undersized to emphasize the height and keep it lite and not bulky. The top with be somewhat thicker so as to finish off the stand as older furniture looks. You might notice that all of the horizontal elements are sized for their location - larger on the bottom, small in the middle, and middle-sized at the top so the top appears to be resting on something substantial, but not too big.

What isn't shown is the joinery. I will mostly use mortise and tenon construction with dovetailed drawers. The doors and sides will be frame and panel construction with flat panels. The most important consideration in the joinery is wood movement.

Wood is anisotropic: its material properties are different along different dimensions. It is strong when stressed along the grain (longitudinally), but weak across it (radially and tangentially). It expands and contracts in response to humidity. This change is very small longitudinally. It is considerable, but unequal, in the radial and tangential directions.

I will talk about this next post.

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