One of the fun things about making this set of stoppers was that I utilized several new materials, or at least materials that I had either not used before or about which I have not posted an entry. From left to right, the materials pictured first are: tulipwood, stabilized redwood burl (2-5), Mopani, American Cherry, Cocobolo, and malachite acrylic.
Tulipwood is one of my absolute favorite woods without question. I love its appearance with cream and pink striping and I even like the smell of its shavings when turning it. This northeastern Brazilian wood should not be confused with its American cousin, also called Tulip Poplar or Yellow Poplar; this is a true rosewood of the Dalbergia genus, decipularis species although some also use the species frutescens. Tulipwood is a costly favorite as it is in relatively short supply and tends to be expensive. Generally only small pieces are available because while the tree can reach 20-30 feet in height, it is rarely more than 1 foot in diameter and many specimens would be more appropriately described as shrubs as opposed to true trees. This means in practice that it is rare to find bowl blank sizes but instead spindle pieces of 1-2” square with various lengths up to 12+”. This means in practice that most tulipwood is used for spindle applications such as bottle stoppers, pens, knife blanks, and inlay work. The wood is quite hard and will dull tools so frequent sharpening is important during the turning process. The hard nature of the wood also means that great care must be taken to avoid breakage during roughing down the blank or during drilling. Some people have experienced difficulty in gluing the wood since it has a fairly high amount of natural oils, although I have never had trouble gluing tulipwood pen blanks with cyanoacrylate. The high oil content also means that the wood takes a high shine easily.
Stabilized Redwood Burls
The stabilized redwood burls were a new product being offered by Woodcraft in not only bottle stopper blanks sizes, but also pen blank and knife scale sizes, and I was eager to try them. I have written about stabilized wood products elsewhere but I have not commented on redwood itself. Of course these blanks are actually burls which are quite different from redwood timber itself. Burls are the result of injury or infection to the tree and they may occur above or below the soil surface. They almost always demonstrate elaborate figure with whorls and curls which make them popular for decorative purposes. Since any one tree cannot be guaranteed to have formed a burl, although the older the tree the greater the likelihood, burl wood is valued as relatively rare and uncommon. Many times, burl wood is brittle, powdery, or otherwise unstable due to its wild figure and lack of consistent grain or cellular structure, making it difficult or impossible to work with. As it is, redwood is a relatively soft wood, although very resistant to rot and insect infestation, and the burls are relatively soft as well. The stabilization process of injecting dyes and resins makes these types of wood easier, or possible, to work with turning and other methods. Sequoia sempervirens trees’ native habitat is only in the Northern California coastal forests ecoregion, on the Northern California Coast and several miles into Oregon. All three species of Sequoia are considered endangered flora, with the two species native to California being classified as vulnerable and the very rare species native to only the mountains of remote Hubei province in China being classified as critically endangered and in fact were believed to be extinct until they were rediscovered in 1948. The Chinese species has even been listed on the International Union for Conservation of Nature (IUCN) Red List based on its high potential for extinction. Large stands and especially large specimens of the California species have been protected in state and national parks, but commercial logging of these species continues on privately owned land, although this practice remains the subject of vigorous debate and protest. The wood is prized for its decorative and endurance qualities especially for decking, siding, and fencing.
Mopani was a wood I had never worked with before and the only pieces I have are intended and sized strictly for bottle stopper turning. Wood suppliers mostly stock spindle pieces although for some considerable dollars, one can obtain bowl blanks specimens. Mopani, also known as mopane, is known scientifically as Colophospermum mopane. It only grows in hot, dry, low-lying areas located in the far northern parts of southern Africa, including parts of South Africa, Zimbabwe, Mozambique, Botswana, Zambia, Namibia, Angola and Malawi.
Mopane wood is one of southern Africa’s heaviest and hardest timber woods and this can make it difficult to work with, but it also is a prime reason that is prized for turning work, an application where hard woods tend to perform better. The wood is highly termite resistant, at least in part due to its hardness, so it has long been used for building such things as houses, fences, and railway carriages. The rich, reddish coloring also make it popular for flooring and of course contributes to its popularity as a turning wood although it has also found use outside of Africa for such diverse purposes as aquarium ornaments, bases for lamps or sculptures, and garden accents. Mopani is also being increasingly used as a replacement tonewood as suitable supplies of quality African blackwood, another true rosewood of the Dalbergia genus (Dalbergia melanoxylon) becomes harder to obtain. Mopani is especially being used for the construction of high-end clarinets in which it is said to produce a warm and rich tone.
Interestingly, the twigs from this tree are also traditionally chewed as toothbrushes! Additionally, the bark may also be used to make twine or used as a hide tanning ingredient, while the leaves are thought to be useful for healing wounds. It may also be used for cooking in the form of charcoal.
In a completely unexpected twist, the tree is also a major source of ingestible food protein since the leaves are a major food source for the mopane worm, the caterpillar of the moth Imbrasia belina. These caterpillars, rich in protein, are widely eaten by local people, and the sale of roasted or dried mopane worms can contribute significantly to rural economies in areas where the trees grow. Finally, in yet another example of non-timber usefulness, Mopani trees are a food plant for the wild silk moth, Gonometa rufobrunnea. Cocoons of the moth are harvested as a source of wild silk that is used to make cloth!
American Black Cherry
American Black Cherry is scientifically known as Prunus serotina. Trees of this type are naturally found in zone ranging from southern Quebec and Ontario to Texas and central Florida. There are also isolated populations in Arizona, New Mexico, Mexico, and Guatemala.
This type of cherry is not the same as that which produces edible fruits. The fruit produced by this type of cherry is generally found to be bitter. Small quantities are however used in flavorings and for cooking. The pits should never be consumed. Branches, leaves, and fruits should be removed the reach of livestock because after ingestion these tree parts release hydrogen cyanide gas, which can severely sicken or even kill livestock.
Black cherry timber is highly valued in the United States and is considered by some to be the premier cabinetry timber produced in the US. The strong red color for which the wood is known will develop over the course of one year after the wood is harvested and worked. Newly made items will appear lighter than those that have been in existence for a longer time. The wood is also used for cooking and smoking foods, where it imparts a unique flavor. The small piece that I utilized had interesting insect damage and one small knot, which adds to the interest of the finished piece although it did complicate turning since it made the piece less structurally stable.
I have written about using acrylic elsewhere, but having reviewed that piece, I feel that I should add some information. I had a MUCH simpler time using acrylic bottle stopper blanks than I have experienced with pen blanks, but that may also be due to the fact that I have more practice and different tools. While I used to use a sharp skew chisel I have switched to the Easy Wood Tools system and find that all I needed to create really stunning bottle stoppers from acrylic was the Easy Rougher! I can’t praise Easy Wood Tools enough and they are my absolute number one go-to tool, often to the total exclusion of any other tool in my shop. I only wish they had been developed before I had invested in all the other items!
Acrylic is hard enough to hold threads and didn’t spin out on the mandrel, so I was able to completely remove the tail stock and finish the top of the stopper without having to part off anything, which meant that I was able to achieve a very nicely rounded top instead of a sheared off flat surface like most of the wood stoppers require. I had no need to sand down the edges first because of the superior performance of the Easy Wood Tools. Heat was certainly still generated and the tool actually became hot, but I had no trouble with melting or marring at all. Instead of sanding with traditional sandpaper, I used newly acquired Abranet manufactured in Finland by the Mirka Company but sold by US distributors. Since the material is actually a net, it has very low potential for loading and can even be washed out and/or used for wet sanding, which works very well with acrylic. This low loading nature and washability gives the material an incredibly long life, justifying its admittedly high cost (about $17-$20 for a pack of five strips measuring approximately 3”x12”). This material is my new favorite go-to for an abrasive and reaches down as low as 600 grit which is more than adequate for any wood material. For the acrylic however, I did use the micro fine sanding pad system (now also available in sheets) down to 12,000 grit for the best possible polish, and finally finished with the HUT Poly Gem as previously noted.
The particular stone and acrylic resin used is sold under the name of Tru-Stone and is manufactured from up to 85% actual stone, in this case malachite and a red stone (in the second photo) that I am not familiar with. I have, in the long distant past, worked in a shop that sold actual malachite pieces and I can attest that the look is pretty near flawless although the feel is of course quite different from real stone, but the look can’t be beaten.
The materials in the second photo are from left to right, stabilized redwood burl, discussed above, rengas tiger, a very soft wood I believe is known as randadillo, and acrylic. The only two materials not discussed are of course the randadillo and rengas.
Randadillo (Mystery Wood)
Randadillo, if I am even correct in identifying this piece as that type of wood, was very soft, which made it difficult to achieve a fine finish with turning tools, but very easy to sand. Whatever it is, I didn’t particularly enjoy working with it and I found the finished wood to be pretty plain. I am completely unable to find ANY information about this wood, and quite likely it is also known by another name with which I am unfamiliar. The exotic wood suppliers I use make no mention of this wood and the only references I can find are from Penn State Industries (which is where I believe this blank came from) and sellers on Etsy who claim to have used it to make, you guessed it, bottle stoppers. If anyone out there knows about randadillo, please let me know! I may be wrong in my identification altogether although I am certain that somewhere in my shop I have wood sold to me as randadillo.
Rengas wood, also known as Rengas Tiger or Borneo Rosewood, (properly known as either Gluta spp. and Melanorrhoea spp, so not a true rosewood of the Dalbergia genus) due to the stripes in the heartwood and/or for its location of origin, is a wood that originates in the Indo-Malaysian region of Southeast Asia. The wood is relatively soft but can dull tools due its unusually high silica content; however it is otherwise easy to work with in my limited experience. Rengas has been used for cabinetry and turning purposes but many people avoid it because of its high potential for causing, occasionally severe, allergic reactions upon exposure to its sap. These reactions are said to be similar to those produced by poison ivy, resulting in blisters and sores, as well as constitutional effects like fever and difficulty breathing in some sensitive individuals. Because of this, foresters are likely to avoid harvesting this wood since green wood has the highest concentration of sap. Dried samples are less likely to cause these hypersensitivity reactions although it is possible. I was lucky and had not issues whatsoever, but I was warned by a large sticker on the blank that listed possible allergic reactions, a notice that was NOT provided by the seller, in this case Penn State Industries, prior to sale. Yet another reason to not use that company… When and where available, it is priced in the medium or moderate range, not cheap but not as costly as some woods.
Suppliers, Finishes, and the End
And by the way, if you are looking for exotic lumber and/or turning stock, I highly recommend both Bell Forest Products in Michigan and West Penn Hardwoods in upstate New York. Both offer excellent products, fair prices, and a WIDE selection of woods coupled with excellent customer service. West Penn Hardwoods often has massive sales on quantity purchases and Bell also runs occasional specials available to former customers or those who register on their website.
All stoppers, except the acrylics of course, were sanded to 600 grit and finished with a two-step process utilizing u’Beaut Polishes EEE-Ultra Shine followed with Shellawax Cream. This is my most commonly used finish process for spindle work since it gives a nice polish and nice color to most any wood without being overly shiny and plastic looking. This is an Australian product but it is sold by US suppliers.
Not only did making these stoppers give me a chance to experiment with new techniques in parting off and spindle turning, but I was also able to play with a wide variety of materials both new, familiar but never written about, and familiar but more workable based on experience and tool selection. I had an overall good experience and I recommend that every wood turner try making bottle stoppers as a relatively quick and fun project.