The availability of such dense wood varies from region to region. One might be considered lucky, in some respects, to live in the deciduous forests east of the Mississippi.
Unfortunately, the very best sounding woods are also those which are the
Included is a list of the woods the author has used for bullroarers. This is a mere smattering of the woods available. Starred woods are those that have proven most successful so far.
Apricot Balu *
Black locust Desert holly
Juniper Freemont's cottonwood
Mango Gambles oak *
Mesquite Mountain mahogany **
Palo verde Osage orange *
Purple heart *River Hawthorne
2x4 pine/fir White pine
Wood lathe
hardest to work. One gains new appreciation for the reverence attributed to an aboriginal bullroarer when one starts to shape a section of Mountain mahogany with an incisor-tooth scraper.
Tools
The level of technology in producing a bullroarer is purelyone of personal choice. Scrapers of various lithic and tooth derivation would have been the norm in pre-history, and in some cultures are still in use today. The tools of choice in a more modern context are the machete, hatchet and wood rasp. In addition, an occasional belt sander or band saw should not be discriminated against. A small blade of some sort is also useful for the final touches, as well as some type of sanding tool; paper, rock, etc.
Design
An ongoing study of the design, weight, dimensional ratios and sound, of (as of now) about forty separate bullroarers, has suggested a general shape and mass as outlined below. Again, it must be emphasized that virtually anything tied to the end of a string and swung around ones head will make a sound. The data here presents one way in which to shape a bullroarer.
Start with a dry relatively knot-free section of wood from forty to fifty centimeters (For an excellent reference on drying times of suitable woods see Time Baker's article in BPT #2). Green wood will work but without the ease of dry wood. In addition a dry blank of wood should not offer as many splitting surprises.
Split the log or branch in half. If the halves of the once whole log are thicker than five centimeters split one of the halves again. Always split the section you are working on at the center of the mass. Trying to split the edge of a section will only result in "grain run-out", making the piece more difficult to work.
Using the tool of choice thin the blank evenly on both sides. Look for the straight longitudinal plane within the wood and then use this straight plane as the center-line of the blank. Thin on either side of the center-line so that the distance from the center-line to the outer edge of the blank is even on each side.
The straight plane is as critical in this early stage as it is in the final stages of finish work. Establish this midline for both side to side, and top to bottom. The center-line plane is the reference for all subsequent shaping throughout the making of the bullroarer. It is the baseline, and must be established early on.
Continue thinning the blank to about one and a half centimeters then start thinking about the shaping. At this point the blank should roughly resemble a rather thin rectangle.
The surest way to shape and avoid any unfortunate shaping errors, is via modified thinning. This is accomplished by working the thinning tool at an initial angle of approx. 45 degrees to the center-line. Thus shaving down the edges of the rectangle from a squared edge to a convex surface. The angle of work allows the scraper to across grain ends ratherthan "catching" an end and diving into the work surface or tearing off an edge grain.
The convex-convex, or lenticular shape of the board is the basic design essential to the finished bullroarer.
The final thinning and shaping can now be done. A template of a selected shape may transfered to the board, or a freehand outline can be applied. As you can see from the photo, the variety of design varies within certain limitations. See the drawings * to get a feel for the overall shape.
In general:
1. Leave distal end thicker than the proximal end.
2. The proximal half should taper in thickness from the center ofthe bullroarer to the thinnest section at the base.
3. The center-line and margins of the biface bullroarer should be straight as an arrow.
4. The bevel from edge to the midpoint of the bullroarer should be equal at all points.
5. An overall shape of 3 or 4 to 1 (length to width) is generally acceptable for best results.
String
Intrinsic to the propulsion of the bullroarer is the string and the hole the string is attached to. The average distance from the base to the center of the hole on the bullroarers under study is 0.9 cm. The placement of the hole is exceedingly important. For the bullroarer to spin without fluttering the string should be an extension of the midline of the bullroarer. Therefore proper centering of the hole for the string is paramount. One easy and safe knot for string attachment is the girth hitch.
Traditionally, the string for the bullroarer was madefrom flax and various other plant fibers, rawhide, and even human hair (refer). Their lengths were as varied as the cultures they came from. A manageable length is about 180 cm, just longer than the fingertip to fingertip distance on outstretched arms.
The string can greatly effect bullroarer performance. Because the actual physics behind the motion of the bullroarer are partially dependant on string performance, the intrinsic values of various strings can make or break the bullroarer's roar. For a prehis-torically correct (PC) string, rawhide or buckskin is recommended. Fora really high performance bullroarer use the modern day artificial sinew. Artificial sinew is a waxed nylon which lends itself nicely to bullroarer performance. A small stickor hide handle on the handheld end of the string can be useful in avoiding blisters and raw fingers. In some cases a long stick may be added to the string to produce extra force in the spinning of small specimens.
Matt Immergut doin' the bullroarer shuffle at Rabbitstick.
The actual swinging of the bullroarer is fundamentally easy. Hold the string high above the head and swing the bullroarer in a plane horizontal to the ground. Take note of the changing pitch and frequency of the sound and its relation to the string action.
A note of caution. Bullroarers build up significant centrifugal force and when unintentionally released (or strings break) can cause serious damage or pain to those around. Please use two strings of artificial sinew, or two strands of rawhide, and experiment with any PC method alone before amazing you friends. Let me know what you discover! Send any new design ideas, comments on performance, records on ethnographic uses, etc. to me c/o BOSS. A study investigating the actual physics of the bullroarer and what's behind the sound is currently in progress.
Carving Green Wood and Curing Wood Carvings
By Gregg Blomberg
Green wood is readily available and inexpensive or free. Beautiful local woods can be found almost everywhere in the US. Salvaging and using this material can be more satisfying than buying some exotic piece at a high price from the lumber yard. All the fruit and nut woods I know of are quite suitable, as are many other species. Here in the Northwest, red alder is our "trash" deciduous, growing rapidly to over two foot in diameter. The wood is splendid for carving green, and if cured correctly is quite beautiful. Another advantage of green wood is that green wood of most species is considerably easier to carve than the same wood fully cured. Some woods, once fully cured, do not carve well at all.
This discussion assumes the carver is working with hand, not power, tools. When working with power tools, there are some advantages to working with fully cured wood. Besides the curing method here described, the use of PEG (polyethelyne glycol) can eliminate checking problems. Although in some cases PEG and/or power carving may be necessary or desirable, I usually try to preserve the quiet and simplicity of carving.
Many carvers stay away from carving green wood because they are worried about the problem of checking. Curing a carvi
ng without checking is always an important consideration for a carver. It is more difficult to successfully cure a carving that has the core or heart of the tree in it, since that is the concentrated center to which all checks run. In some woods, the heart itself is so full of stress that checks can begin there.
Checking is of course due to stress in wood. The crack opens up to release the stress. Stress increases with squirrely grain, knots and other irregularities. The checking that happens as a carving is drying is usually the result of unevenness in the drying process. If the wood on the outside of a carving is quite dry while the inside is still damp, the outside wood will not have enough elasticity to absorb the internal movement and must release it with a check.
An examination of early Northwest coast work shows the aboriginal carvers understood their medium well. Most Northwest coast work is hollowed out: bowls, masks, rattles, canoes even the backs of poles. This hollowing allowed for a uniform thickness and thus even and unstressful drying. In some cases, carvings were pierced and relieved in what would otherwise be a heavier area hard to cure without checks. These relieved areas were integrated into the carvings to enhance the design.
If you are carving solid work, is it possible to relieve the carving by hollowing out the bottom, running a drill up through it and/or piercing the heavier areas? If not, you may need to work with fully cured wood and probably should avoid the heart as well.
If you procure a piece of green wood and are not able to proceed with carving it right away, it will be important to preserve it from checking. When curing in the round, checks may start on the ends of the log but they will usually run into the block only to the place at which the moisture transmission through the bark equals that through the log ends. Try to obtain the log with extra length. Painting the ends while leaving the bark on will usually contain the checking. Bruce Harvy of Orcas Island cures a lot of wood for instrument making using a mix of half paraffin and half paint thinner to coat the log ends. Any material that slows down the movement of moisture will help. Wood prepared in this way should be stored in the shade in a cool place. It will take years for most wood so stored to fully cure.
Another way to preserve wet wood for a short time is float it in a rain barrel or some such. Wood saturated with moisture will take up color from minerals if they are present in the water, and once it is removed it must be carved in a fairly short period of time. The loss of this artificially-induced moisture seems to take place more rapidly than the loss of the original tree sap would.
Yet another way to hold green wood for a short time is by placing it in a plastic bag or wrapping it in damp moss. Alder and many other woods are quite prone to rapid spalting and break down under these conditions. Likewise they cannot for any length of time be cured in the round as described above. A month or two will be the maximum you can hold most wood species under these conditions. To lengthen this time, remove the wood from the bag for an hour or two every few days and turn the bag inside out each time you wrap it back up. In other words start a slow cure.
When carving green, the carver does everything the same as with dry. The difference is that in-between carving sessions, the carving is kept in a plastic bag. Upon completion, the carving is treated to longer periods of time outside the bag. Each time it is replaced in the bag the moisture in the piece is equalized, as is the stress brought on by unequal drying. I usually leave the bag open a crack in between as well. Depending on the carving, it will take a week or two to fully cure the piece. I do all but the final strokes, mostly cure the work and then finish it.
Some checks do not detract from the value of a carving, but if checks do start to open up that threaten to compromise the value of your work, try stabilizing them with super glue. Super glue has very low viscosity so it can penetrate deeply. I have used it quite successfully in wood, bone and other materials.
Once I needed a mask in a hurry. I had but three days to work with. To my dismay I didn't even have a block of wood to use, so I cut down a green alder (June). I carved the mask to about 3/8" to 7/16" thickness. To cure, I left the mask on the table and, examining it hourly, patted water on to the end grain where the checks were wanting to open up. Overnight I placed it in a plastic bag. By the third day I had it fully cured and painted (acrylic of course). To this day the piece hasn't checked. From growing tree to cured carving in three days!
Making A Northwest Coast Ladle
Text and Illustrations By Gregg Blomberg ©1987
A Northwest Coast spoon or ladle is a useful and fun carving project, simple enough for the novice and interesting enough for a seasoned carver. Carving a ladle is certainly a useful introduction to work in the third dimension.
To make a ladle I would use a marks-on-wet-wood pencil, a small hatchet and a crooked knife. A shaping adze would also be very helpful to start the hollow and shape down close to the drawn line.
Traditionally these ladles were made from a round of wood just large enough for the object. The advantages are obvious- a small round of wood is easy to come by and there is minimum waste wood to remove. The large ladle in the drawing will require a round of wood 12" long by about 3.5" in diameter (after removal of the bark). Don't hesitate to make your own templates if you have a different size block of wood.
I recommend using red alder and carving it as green and fresh as possible. In other areas, birch, beech or other woods may be more available. Examine your round foe flaws. Often you can lay out so as to evade problems with knots, etc. To avoid checking, keep the carving in a plastic bag between carving sessions. Carving through the center of the block will rarely cause any special checking problems if the methods used are correct (see "Curing and Carving Green Wood", this page).
Begin by peeling the bark off with the crooked knife and lay out the top view of the template with the pencil. Cut out the templates and center the top view template on the blank wood. Draw the line freehand while "eyeballing" where it should be on the round (If you fold the template, you will have a different shape). Do it as neatly as you can, keeping the ladle centered. Afterthe initial drawing, refine the land freehand. Then waste the excess wood with a hatchet or adze. Keep cuts square and parallel with each other. After roughing the first dimension, carve right down to the lines with the crooked knife. Next, lay out the side view template. Hold the template flat and eyeball the lines onto the block. This really isn't difficult, and you continually take every opportunity to refine the work. The carving doesn't have to be exactly like the template to be correct. Waste the wood in the second dimension, then carve the hollow and round off the back.
Leave a crooked knife texture on the piece and finish with mineral oil. Look in museums and books on the Northwest Coast for other ideas and variations. Good luck and have fun.
OBSERVATIONS ON A HAFTED ADZE
By George Price
I carve a lot of soapstone sculpture, pipes, containers, etc. Usually I rough out the piece with a hatchet and finish with a rasp and sandpaper. Recently, while chopping out a bowl, I ran into a problem. The hatchet head wouldn't reach into the deepening bowl cavity. I needed an adze. I had lots of raw material but I chose some tough Morrow Mountain rhyolite, thinking harder to make, harder to break. I modeled my adze roughly after pictures I had seen of Dalton adzes, small, thick, parallel-sided oval bifaces. My adze was also planoconvex in cross section, the flat bottom would seal firmly against the haft element of the handle with the distal end buttressed. See illustration. The handle was made from a fork in a dogwood branch. The head was lashed on with a single strip of soaked rawhide 1/ 2 inch thick. The rawhide shrunk around the contours of the blade. No adhesive was used nor was it needed. This tool has been through some rigorous pounding and the haft has held firm.
This is a very effective tool for gouging out soap-stone bowls and for finer shaping on sculpture because it gets into tight places that a hatchet can't reach. Its main advantage is that the blades are readily interchangeable. Just soak the business end in water for about two hours and unwi
nd the lashing, haft the new blade, let the rawhide lashing dry overnight and the tool is ready to use. No messy adhesive.
I have two blades for my adze. The small rhyolite blade, which is good for late stage bowl manufacture such as thinning walls and final shaping, and a larger blade made of Fort Payne chert. It is heavier and packs more of a wallop making it preferable for early stage roughing out and shaping, like an axe instead of a hatchet for chopping wood. The blades have taken on the characteristic adze wear pattern, polished bit with micro step fractures. The more vitreous chert adze is more prone to step fractures and occasionally large spalls fly off which effectively resharpens the blade in use. You can't get that with a metal tool The smaller rhyolite adze does not have this feature which renders it less effective in terms of time spent resharpening the tool. It is a very difficult tool to resharpen because of the angle of the haft. I could not resharpen the rounded bit of the rhyolite adze using an antler tine but again it can be unhafted and resharpened. The cost being the extra time spent.
Primitive Technology Page 21