Notes On Box Turning And Design

Beginning Box-Turner Common Problems

It has been my experience that turners learning to turn boxes all seem to experience the same problems to a greater or lesser degree depending upon their prior turning experience. And I will outline these problems below and offer some ways of practicing that should be helpful. I turn mostly boxes with over-fitting lids and the discussion that follows applies to them.

To turn boxes, a turner must have basic skills with gouges, skew chisels and scrapers. Assuming adequate skill with these tools, the problems most often experienced are the following:

• Hollowing the body
• Turning a true cylinder in the lid, which is absolutely essential
• Fitting the spigot to the lid so that the box can be turned as a whole
• Fitting a jam chuck to the body so that the bottom can be turned off.

There are several ways that one can hollow out the body. I use the back-hollowing technique and Richard Raffan gives a very good description in the afore-mentioned book of how this is done. This technique is very fast but takes time to learn. Another technique is to treat the box like a bowl and cut in with a gouge from the rim to center. This technique works, but it leaves a rough surface as you are always cutting into end grain. Roughness does not matter when roughing out a box but it matters a lot when finishing one. A third technique is to use the gouge as a drill and drill out the center of the body. Then, starting at the top, take a cut from center to the edge. This technique will give a smooth cut since you are cutting with the grain.

The back-hollowing technique is well worth the time required to become proficient with it. Boxes are hollowed in seconds not minutes and the cut is reasonably smooth. I always hollow my boxes in this manner. As you gain experience, you will want to try the many exotics that are available. Exotics are usually available in some state of air drying. That state varies from quite wet to quite dry. Burls are almost always sold as partially air dried and may be quite wet as well. Partly for this reason, I always rough out my boxes. The other reason is that even in bone dry wood when the insides are removed the wood will move a little. When turning wood known to be dry, I rough out the blanks and let them sit for a couple of hours minimum, but preferably over night, prior to completing them.

To practice hollowing, get some inexpensive scrap 2 or 3 inches square or round and rough out down to about 2 inches deep. I recommend a 1/2 inch gouge made from round high-speed steel rod for this operation. It is imperative that this gouge have a round fingernail shape and a long bevel. That is, the gouge must not be pointed and the bevel must not be steep. It should be possible to remove this waste in 10 to 20 seconds and 30 seconds at the outside. One must be careful when roughing out in this way not to turn a v-shape in the side of the box. It is easy to get the side too thin at the apex of the vee. The curve inside should be a nice flowing curve and the sides should be about 1/2 inch or so thick depending upon the species of wood and the degree of dryness. It is also important that the thickness be even all around including the bottom. Of course, there will be extra thickness where the curve sweeps around the bottom. i.e. the bottom will be thicker at the sides than in the middle because of the curvature. I have never had a problem due to this difference in thickness.

The lid spigot recess must be turned with parallel sides. If the recess is not a cylinder, then it will be very difficult and frustrating to get a decent fit between the lid and the body spigot. This is where things frequently go wrong. The tool that I use for this operation is a standard 1/2 inch flat scraper that has a sharp edge at the top on the left side. The front edge of the scraper is ground to about an 85 degree angle with the high point to the left. To maintain the sharp top edge, I use a coarse diamond hone; I do not grind the left edge after I create the sharp top corner. The way that I cut the recess is to push the scraper in to the required depth and then test the cylinder with a spring-loaded inside caliper with an adjustment wheel. These tools cost about $10 at a good hardware store. If the sides of the recess are parallel, the points of the caliper will just touch all the way along the side wall. And you will feel that the tension on the caliper as it is pushed in or removed is the same at every point along the wall. If the sides are not parallel, take off more wood where the caliper indicates the side requires trimming. I generally get this right in 3 tries. At first, it takes longer.

To practice turning a cylinder, get some inexpensive wood and try turning recesses 1/2 inch deep and 1 1/2 inches in diameter. A recess of these dimensions would be about right for a box 2 inches in diameter. Keep practicing until the operation does not seem so difficult, as it will as first. Poplar works well for practice as does scrap from the wood pile IF it is not split.

To fit a spigot to a lid, I turn a shallow taper, using a skew chisel, on the spigot so that the lid just fits over it and makes a little rub mark about 1/16 inch from the end. This mark indicates where the lid fits exactly. I then use the chisel with a very light peeling cut to bring the diameter of the spigot down to that of the rub mark. We are talking very small differences here. I find that it helps to reduce the speed when finishing up a spigot. At a slower speed I am not taking off as much wood as I would be at a higher speed. If you have a variable speed lathe, by all means turn down the speed.

The fitting of the lid and spigot is done twice. The first time, the fit needs to be tight so that the lid and body can be turned to design as a unit ( but not so tight as to split the lid ). The second time, the initial fit must be eased so that the lid can be easily removed. I like a fit so that the box can be lifted by the lid without the lid coming off. I will accept a lid where the body slowly slides free of the lid as the box is gripped by the lid and raised from its table or shelf.

To practice fitting a spigot to a lid, you can drill out the lid using a Forstner bit. Then the lid will be sure to have parallel sides and you can experience the feel of a perfect cylinder when testing it with inside calipers. Or you can turn it if your skills are at a good level. Such a “lid” can be used for several practices. Once you can fit a spigot to a lid, you should have no problem fitting the body to a jam chuck. The procedure is the same.

It will pay large dividends later on if, in the beginning, you practice these techniques until you feel comfortable with them. Then I suggest starting with domestic woods that are easy to turn. Cherry, ash and genuine mahogany are all good choices.

How to Scale Designs Up or Down

From a photograph or a drawing take millimeter measurements of the major dimensions. (Scaling with millimeter measurements is much easier than using imperial measurements. Translate to imperial measurements later if you desire to do so.) These measurements are entered in the ‘Original Measurement' column in the table below. Next, select one of the dimensions as the base. For example select the diameter or the total height. Divide each measurement by the base and record the result, rounded to 3 decimal places, in the ratio column. The table below has two ratio columns. The first treats the diameter as the base; the second treats the total height as the base. I usually calculate height ratios only for height measurements and they are useful for assessing the protortions.

To create a new design, multiply all of the ratios by the new desired dimension. In the table below, a new diameter of 72mm was used. Scaling down works the same way.

WARNING:

Scaling designs this way is similar to scaling cooking recipes up or down; you always have to make small changes to the end result to get things to taste right. The same is true here. Take the new measurements and make a block drawing. Then make any changes that appear necessary. Then and only then turn an example. After that, you may want to make other changes …

Finally, realize that slavish adherence to measurements can result in a technically correct piece that is artistically dead. Keep measuring to a minimum and learn to trust your eye. You will be amazed at how quickly the eye becomes trained.

You can do this with a calculator (error prone) or you can do it with a spreadsheet program, such as Microsoft Excel, on a PC. I have provided such a spreadsheet (Excel) on the download page.

Turning a Good Fitting Lid and a Good Looking Join

In addition to turning a cylindrical recess for the spigot, it is necessary for the mating shoulders to slope away from each other. So, when completing the lid, turn a bevel of a few degrees on the end of the spigot recess where it mates with the shoulder at the base of the spigot. Do this on the shoulder at the base of the spigot ( on the body ) as well. This will ensure that the two pieces fit together with no unsightly gaps. If you fail to do this, then there will be a gap that will open and close with the seasons.

Do not be fooled into thinking that you can turn the join perfectly smooth and have it stay that way; it will not. In even the most stable woods, the lid and the body will move relative to each other. This may take a few days or it may take a few weeks, but it will happen. Because of this inevitable movement, you need an obvious break of some sort to soften or disguise the fact that there is a slight diameter mismatch at the join. On my boxes, I most often use a pair of beads, but sometimes I just use one or more v-grooves. I adopted the two bead solution from Richard Raffan and I use it a lot. But a single bead will do, and it can be on either the lid or the body. And a single bead at the join can also help if the proportions are not quite as you would like. If the body looks too tall in relation to the lid, try a single bead on the body at the join. Similarly, if the lid looks too tall, a bead on the lid at the join may help.

How To Save Some Money

When you start using expensive exotics, which are in the $20 per board foot range and up (mostly up) minimizing waste becomes an issue. Consider an example: Suppose I make boxes using a technique where the waste is 3/4 inch each. If I can cut that down to 3/8 inch, I can save some serious money. Here are the numbers. Suppose that I make 100 boxes. Further suppose that I save 3/8 inch on each one by reducing my waste. That results in 37 1/2 inches in wood that can be made into boxes that would otherwise have ended up in the trash bin as waste. If my boxes require a blank 4 inches in length, then I gain an extra 9 boxes. If I wholesale my boxes for $50 each, I gain an extra $450 in income – not too shabby.

The way that I reduce waste is to use a scroll chuck for roughing out my boxes instead of mounting between centers. When mounting a box blank between centers, both the driving center and the tailstock center will damage the end grain. At the headstock you may loose 1/4 to 3/8 inch and at the tailstock typically 1/8 to 1/4 inch. My designs call for a 1/8 inch chucking spigot at the top of the lid and at the base of the body. If I use a thin parting tool to make the parting cut, then there will be 1/8 inch of waste there. But the chucking spigots are not necessarily wasted! At the lid, the chucking spigot can provide material for a little pavilion or it can provide material for beads. At the body end, depending upon the design, the chucking spigot may be usable as well. So, with the right design I can have as little as 1/8 inch of waste. I find it interesting and challenging to try and come up with designs with as little waste as possible. It is not possible to get waste down to zero, but as you have seen above you can get close.

When mounting box blanks for roughing out as I have described above, it is safer to use the tailstock for support. I have been hit in the head several times by box blanks that came out of the lathe and I am glad that I always wear an Airmate with a hard hat and a face shield. The revolving center that I own (see photo) is one that has interchangeable points plus a little plate to which I can attach scraps of wood. Using one of these plates, I have made a center out of wood with a leather washer glued to the end which contacts the wood. This way, I can support the box blank in the chuck without damaging it at all. If you do not have such a revolving center, then make a wooden piece that fits over the cup center -- and insure that the grain runs along the lathe axis.

Observations And Comments On Design

Design is an intensely personal activity and is a difficult subject to teach. Both Richard Raffan and Ray Key have written about box design in their books and elsewhere. See “Turning Boxes with Richard Raffan” and “Woodturning & Design” by Ray Key for their views. Chris Stott has written a book, “50 Designs for Boxes” where he presents some of his designs. The views that follow are some of my own thoughts on the subject.

Let's begin with a story:

In the late 80's I attended a weekend woodturning event where Del Stubbs was the featured demonstrator. During this time, I was struggling with design issues as they relate to boxes. During a question and answer session I asked “If one uses the 2/5 to 3/5 rule for proportioning the height of a box, what is the design rule for determining the diameter?” Before Del could answer, another professional turner said “There are no rules when it comes to design.” That comment would have been OK if he had left it there. He is, after all, entitled to his opinion. But he went on to say – in Latin – “Only a moron would ask such a thing.” He must have thought that I could not speak Latin; I can. I felt the color rising and started standing up with a sound thrashing in mind. My wife stopped me and said, “Let it pass.” which I did. (But I still owe that guy a good thrashing.)

Let's consider the premise “There are no rules when it comes to design”. It takes only one counter-example to dispel an assertion, but I will give several. Have you ever ridden in an automobile? Probably you have. Did you notice that the wheels and tires are circular? Have you noticed that cars with square wheels and tires are not selling well this year?

Then we could state that it is a design rule that automobiles shall have wheels that are circular.

You probably eat your meal while sitting at a table. How many tables have you seen where the top surface is 6 feet above the floor?

We could state that it is a design rule that the surface of a table shall be about 30 inches above the floor.

The point is this: the objects we make must accommodate human beings and human beings are the object or our marketing efforts. (I have never sold an item to an extraterrestrial.) Human beings exist within a set of pretty well defined limits. The tallest adults are less than about 7 feet tall and the shortest adults are more than about 3 feet tall. Near the middle of this range is what is taken as “normal”. And so our objects are usually made to accommodate a “normal” human being. Because of this, there are design rules. People that design furniture have numerous rules-of-thumb, or design rules, that they follow, as do artists who draw, paint and sculpt the human form.

The way that human beings perceive objects is a result of how the human brain works. Have you ever gone outside on a warm summer day and lay on your back and watched the clouds move across the sky? If you have, then you will have noticed that if you look at a cloud for a while it starts to look like something familiar. The brain is trying to relate a new shape to something it has seen before. Because of the way our brains perceive images we tend to prefer the proportions that we do. Consider having a print matted for framing. The mat will be a bit thicker at the bottom than at the top and sides. This is because if it is the same all round, the brain will perceive the mat to be too thin at the bottom. We could state this as a design rule. Tall columns are usually larger in diameter in the middle than at the top and bottom. This is because if they are exactly straight, then they will look thinner in the middle. And so on.

If you look at objects from antiquity through the present, you will see the same proportions used. Styles come and go, but the underlying proportions remain the same. Humans from antiquity were still human and they had the same brains that we have and they perceived form the same way that we do today. If you ever travel to England, try to visit the Birmingham Museum and Art Gallery, home of the Pinto Collection of treen. There are 6 thousand older items, many turned, on display for you to study.

Because the owners and users of our boxes are human beings, it must be possible for a human to get the lid off. Most of the boxes that I sell are purchased by or for women. Women tend to have smaller hands than men and they are not as strong. So, for boxes four inches in diameter or more you may want to consider loose or nearly loose lids. For two and three inch diameter boxes the lids can have a soft suction fit and most people will have no difficulty getting them off.

The box block diagrams that I have published on the download page and on the box designs page illustrate various schemes for designing a box. You can look at these and decide which ones you like. These examples show that there are several ways to get at essentially the same result. Most of those boxes use the golden mean (0.618) as a proportioning scheme. But the squat or short ones use 4/9 for proportioning. That is, the lid is 4 parts the body is 5 parts and the height is 9 parts. Both of these methods work well and the end result looks good to me. Another proportioning scheme that works well for short boxes is ¾. In that method, the lid is 3 parts the body is 4 parts and the whole is 7 parts. Some turners also use 1/3 for proportioning. In this scheme, the lid is 1 part the body is 2 parts and the whole is three parts. It is my view that the 1/3 scheme is the lower limit for acceptable proportions; I think that a lid less than 1/3 the height looks too short and stingy. Stay away from ½. An object divided into two equal parts will look unsettling and top-heavy. Like the bottom part of a picture-frame mat, the bottom portion will look too thin if parts are the same height. The only exception to this statement that I have seen is the mosque box that Richard Raffan used to make. These boxes look fine if the lid and body are the same height. The reason is that the major mass of the dome occupies about 2/3 of the height of the lid with the remainder of the dome sweeping in to a narrow finial at the top. The lid has the illusion of being shorter than the body.

I like my box lids to be a bit shorter than the golden mean specification (38 percent) calls for. So, when I am designing, I use 36 percent of the total height for the lids and 64 percent for the bodies. This will make little difference in short boxes but will add a few millimeters in the taller ones and I like the result.

When I have a new idea for a box, I will make a pencil sketch of a half-profile -- to scale -- on graph paper. I will then make any adjustments that I think are needed and I will indicate the major dimensions. Following the sketching, I will scan the drawing into a graphics package on my computer. A simple package such as Microsoft Paint, supplied with Windows, will do nicely. I then make a copy of the sketch and rotate it so that it is a mirror image of the original. I then put the two images together to get a full two-dimensional rendering of my idea. The two-dimensional image may need other changes to make it look like the picture in my mind. Once this is done, I may clean up the drawing using the editing capabilities of the paint package. I will then print out the drawing and take that to the workshop. All of this may take one hour from start to finish. In the workshop I will turn a prototype and see if it needs further changes. If it does, I will turn another item with the changes incorporated. I will then continue this process until I get what I want. When satisfied with the result, I update the drawing – on the computer – for future reference. All of the box diagrams that I have placed on the two pages for your reference have been around for at least 10 years and it is due to my saving and documenting them that they are available today. I think that it is worth the effort to preserve your designs especially if you turn boxes only sporadically.

Which Chuck Should I Buy?

For several years I used collet chucks from Craft Supplies UK plus a Raffan chuck. These were all supplanted by the Nova chuck, a scroll chuck, after a couple years. The Nova is still available and I still use mine. For the last 15 years or so I have had an Axminster Precision Chuck. Until recently I used that chuck for 95% of the work that I do, and I do a wide range of work. Recently I purchased a Vicmarc 300 lathe from Australia and I included in the purchase a Vicmarc scroll chuck of the type with Tommy bars. I use this chuck whenever I need a very wide range of adjustment in the jaws. The Tommy bars make adjusting the jaws in or out a very quick process – unlike the keyed type. The Vicmarc chuck with the “shark jaws” attached is unsurpassed for roughing out boxes. It has a wide range of adjustment and the deep jaws minimize the likelihood that a blank will get ripped from its grip by a catch. But I still use the tailstock for support for blanks 3 inches or more square. I also like the other jaws that are available for the Vicmarc – I have them all – and I find myself using this chuck more and more.

The Axminster chuck is my favorite for finish-turning boxes, especially small ones. The Axminster has available jaw-sets specifically designed for turning boxes. These jaws are available in 1 inch, 1 ½ inch and 2 inch nominal diameters and they are shaped so as to present a minimal danger to ones hands and fingers while in use. The 1-inch jaws are also useful for gripping wood dowels or metal or nylon rods for use as mandrels. I have heard some professional woodturners state that the Axminster chuck is “a dangerous chuck”. Their reasoning is that because it does not have a pin to prevent the jaws from being wound out, it is dangerous. It is true that the Axminster lacks such a limiting pin. But I have used one for at least 15 years and have never had an accident. But I have cultivated the habit of always checking that the number 4 jaw is gripped by the scroll before switching on. I think it is much more likely that one will unintentionally leave a key or Tommy bar in a chuck and switch the lathe on. And I have never done that either. I think that each individual needs to understand what the risks are with each piece of equipment that they use and make a decision about what is acceptable and what is not. All powered machinery has the potential to cause injury and chucks mounted to a lathe are no exception.

So, what do I recommend? If you are turning only bowls I recommend the Vicmarc with either Tommy bars or a key. The Vicmarc has bowl-gripping jaws up to 8 inches in diameter and is ideal for bowl turning. If you are turning mostly boxes, I recommend the Axminster. One advantage of the Axminster is that interchangeable sets of jaw slides are available to which each set of jaws can be attached. This makes changing jaws quick and easy. But the jaw slides are not cheap. Ideally you will eventually have both chucks as I do. Professional turners will have many chucks with a particular jaw set attached to each. This way, they never have to stop production to change jaw sets.

There are several other brands of high quality scroll chucks available commercially that I have not mentioned. That is because I have no experience with them and so cannot comment about them. You should not interpret their absence here to be negative.

References

There are not many books and videos about the design and turning of boxes. The ones that I know about are given below.

Books

I have read these books and can recommend them highly. The book by Chris Stott presents the designs with little discussion about the designs.

"Turning Boxes With Richard Raffan” by Richard Raffan, 1998, The Taunton Press

"Woodturning And Design" by Ray Key, 1985, B. T. Bratsford Ltd.

"Turned Boxes 50 Designs" by Chris Stott, 2002, The Guild of Master Craftsmen Publications Ltd.

Videos

I have these videos and can recommend them highly.

"Turning Boxes With Richard Raffan” companion video to book above

"The Basic Box" by Ray key

"The Finial Box" by Ray Key

"The Capsule Box" by Ray Key

The following videos are available but I have not viewed them. Chris Stott is a highly competent English woodturner. Bonnie Klein is a very talanted Amrican turner.

"Turning a Box with a Fitted Lid" by Richard Raffan

"Turning Boxes" by Chris Stott

"Inlaid and Novelty Boxes" by Chris Stott

"Turning Boxes with Threaded Lids" by Bonnie Klein