the Carpentry Way: Mizuya (4)                                                          

Mizuya (4)

Now we come to a tricky part of the design: drawers. Now, drawers, per se, are not generally an inherently tricky thing, though getting a good fit can certainly be a challenge, and there are different ideas out there among the drawer making fanatics as to what constitutes a good fit. There are aesthetic factors to consider of course, whether to mold or bead the drawer front, what sort of pulls to fit, etc. Those are matters to work out to be sure in this build, but the tricky bit for me at this juncture concerns drawer construction.

I've set myself up to struggle in this cabinet build by trying to use glue and/or metal fasteners absolutely minimally, and as one commenter, given those constraints,  noted a few posts back that he'd,  " to see how you make drawers". Hah! I have been wondering much the same thing myself. This is not the first time I've pondered drawer construction in depth, though it has been a long time since I made a cabinet so drawer construction issues have been well on the back burner for some time now. Not any longer, so let's proceed....

At the outset, there is a fork in the road, design-wise: metal sliders or not. Metal sliders are strong and smooth, easy to install, and replaceable. They allow the drawer to be opened all the way for full access to the contents, and there are even fancy soft-close mechanisms for them. On the flip side, those metal mechanisms take up a certain amount of room, and that room has to be subtracted from the drawer itself. Drawers with metal slides have a drawer face which promises capaciousness, however it is not something that is delivered when the drawer is opened. Also, the construction of many drawers these days involves a box to which a face - a facade - is affixed, and this doubling of the front elements seems wasteful and the facade part does not appeal much, if simply on philosophical terms. But really, more than anything else, because this is a cabinet modeled on traditional lines - my interpretation of them at least - I really can't 'go there' with the metal drawer slides. So, my drawers will be all wood.

Going 'all wood' still leaves one with plenty of choices, and in fact there are possibilities to use wooden substitutes for the metal slides, like dovetailed side-mounted battens, and so forth. I gave those sorts of mechanisms some considerable thought, but I saw an issue in there, literally, with wooden drawer slide mechanisms, where the combination of dust and dirt, wearing surfaces, and shrinking/swelling materials tended to suggest to me that performance may not be great for much of the year. In other climates perhaps, but not around these parts where humidity cycles are vicious.

So, that would appear to, er, draw things down a bit, wouldn't it? Now all I need to worry about is how to put a drawer box together. Ignoring the quick and cheap options of biscuits and dowels, the typical way of joining the drawer sides, front, and back, together involves carcase joints - either finger joints, or dovetails. In western culture I observe a veritable fetish has developed around dovetailed drawers. Indeed, when I check out a cabinet, one of the first things I look at is the side of the drawer to see how it is attached. Dovetails, if well executed, are a good sign, but let's face it, there are only a sign and not the whole story. The larger furniture makers seem to know this piece well, as machined, gang-cut dovetails are fairly common on middle-grade furniture and up - at least on the joins between the sides and front of the drawer. The back of the drawer is often attached in an after-thought sort of manner, nail-gunned in there. A guess a lot of folks can't tell such a dovetail from a finely made one, or could care less anyhow. This is very similar to the bicycles one sees for sale in stores, where the manufacturers will often throw on a flashy handlebar and pimp rear derailleur, while skimping elsewhere in the important places where people just don't notice, like the spokes, bearings, hub spindles, etc. Just another aspect of our make-believe, stage-set material culture.

The typical well-constructed drawer will often be dovetailed at all corners. Vast battalions of woodchucks out there, obsessed with dovetailed drawer work, will hand cut the drawers so the pins are as slim as practicable, showing clearly, proudly and loudly, to a world that cares not, or is stubbornly unaware, that they cut their dovetails by hand. They may have machined the rest of the joints, but the dovetails are sacrosanct for some reason, and you're really letting the side down if you don't hand cut them. This is not something I believe personally. So long as the joint is well cut and fitted, and mechanically sound, that is that main thing to me, and if that result is obtained by many hours of contemplative sawing and chiseling, or blasted out with a Leigh jig, all good. Either way, the execution can range from 'flawless' to 'hack job'. I realize that for some out there these dovetail decisions are life-and-death, "I'll never speak to you again", sort of matters, but not here, where I have other obsessions, other fish to fry.

Dovetail variations include through-dovetails, blind dovetails, concealed mitered dovetails, and a few others. Often the sides of the drawer are made in a secondary wood like maple, oak, etc, which is light in color and given the darker wood for the drawer front provides maximal contrast to the dovetailed joint. This is to make extra certain that the world can see those dovetails - if they are paying any attention at all, which, most of the time, I would suspect they are not.

All that said - and I am poking a little bit of fun in my commentary above- a carcase dovetail is a strong and attractive joint. Well, it is if it is cut well. It is also a joint that, while having good mechanical interlock, is a glued connection. Indeed, given some of the popular practices of undercutting the iside faces of the tails and pins, the glue is often a large portion of the mechanical connection. 

I've been thinking about whether there might be another way to put a drawer together, but before I get into that I wanted to look at another aspect of drawer construction which is fairly significant - the floors, and how they connect to the rest of the drawer. The first choice is between solid wood floors and plywood floors. I'm going for solid floors. Plywood floors are very practical, easy to make, etc.,  a perfect compliment for the metal drawer slides - and I have similar reservations about how appropriate they might be to a 'traditional' piece. In order to deal with the solid wood movement issue, the drawer bottoms will be quartersawn material, and they will be attached to the rest of the drawer so that there is build-in accommodation for movement.

And how does one attach drawer bottoms to the rest of the drawer? Well, there are three methods I'm aware of:

  1. Nail and/or glue the drawer to the bottom of the drawer carcase.
  2. Cut a dado in the drawer side and front, cut a tongue on the panel, and slide it into position.
  3. Use a dadoed drawer slip.
Method 1 is commonly seen on Japanese tansu, affixed crosswise to the run of the drawer, and I just don't think it is a good way to do things. Usually the 'nails' are actually wooden pegs, other times, on cheaper pieces, they are metal. One advantage to this simple attachment method is that it maximizes available interior drawer space. Against that, however, even if one employs floor panels which do not move too much seasonally and cause a problem, eventually the nails corrode a bit, the glue bonds start to fail, and then the connection between floor and carcase weakens. One day you open the drawer and the bottom is starting to spearate away, with bits and piece getting jammed in the crevice. The owner then attempts to repair the floor separation with more glue and metal nails, often splitting the boards as they are driven in, and if these bits of metal stick out they can trash the runners inside the cabinet. Finally, the entire drawer runs in and out of the cabinet on its floor, which is a lot of surface area and friction. The drawers are typically quite light in weight so this friction is not a huge problem, but in a heavy wood it would be. I'll give that construction method a pass.

Method 2 is quite a common one, and a method I have used in the past. It can provide a strong connection between the floor and the rest of the drawer, and allows for wood movement, however it is not without its defects. The two principal defects are this: the dado in the drawer side weakens the lower portion of the drawer side significantly; and the raising of the floor panel up to fit in a dado means that a certain amount of potential interior space is surrendered.  One solution to the weakening of the drawer side from dadoing is to simply make the drawer side thicker, but in most cases one could anticipate a drawer side having to be in the range of 0.625"~0.75" to remain adequately strong, and that incurs a drawback of making the drawer heavier, both in actual weight and in visual terms, and the thicker sides mean potential interior space gets gobbled up. Many drawers built with dadoed floor panels also feature triangular glue blocks on the underside to reinforce a vulnerable area. You'll find these many years later sitting in the drawer below, having fallen off from one moisture cycle too many.

Another drawback to the commonly seen method of dadoing in the floor panel into the sides and front of the drawer is that the drawer then runs in and out of the cabinet on the surfaces of the drawer side lower edges alone. Taking a drawer in and out thousands of times, particularly if it gets loaded up heavily, entails all the wear and tear being concentrated on these relatively narrow strips, and something has to give in either the drawer's lower edge or the cabinets drawer runners, whichever is softer yielding soonest. Given the dado already weakening the lower portion of the drawer side as an issue, add in the wearing of that lower edge making the remaining mean left below the dado thinner and thinner, which means weaker and weaker.

A solution seen, as it turns out, in English high class cabinetry, is our number 3, drawer slips. Drawer slips are a piece of wood, dadoed to accept the floor panel, which are glued to the lower inside face of the drawer side. Here's an example a couple of different drawer slips, in cross-section view:

Some slips have an upper edge flush to the drawer floor, others are done so that the slip is proud of the floor. In either case, it is possible to profile the slip if so desired. 

A view of a slip attached to the inside of a drawer, all fitted together:

I trolled the internet for pictures of drawer slips, and found a short article on them on Popular Woodworking's website, which is where the above image originates.

Slips solve a lot of problems just by gluing a little strip into place. The eliminate the problem of weakening the drawer side from dadoing, and, because the dado is no longer in the drawer side, related problems with dovetail placement on the lower portion of the side are solved. The applied slips widen the effective lower edge of the drawer, and that means that the load is spread out over a greater area and thus wear and tear issues are greatly ameliorated. It's a clever solution.

The drawer slips are typically attached to the drawer sides, though some also affix a slip to the drawer front, which means that the slips could meet one another at a miter if so desired, perfect for those nosy house guests who not only want to inspect your drawer dovetails but want to pull the drawers out and examine the bottom as well.

I really like the drawer slip method, and if I were not so concerned with the glue minimization issue - if I wasn't so otaku about that - I imagine I would be perfectly happy making dovetailed drawers with mitered slips. I've been tossing and turning and scheming however to see if I could put a drawer together without using glue, with solid wood, and with joinery, and I think I may have hit upon a solution. I may also be barking mad - jury is out still. I'll share the delirium with you in the next post in this thread.

Thanks for coming by the Carpentry Way. I hope to see you next time 'round. On to post 5

Labels: , ,