Segmented bowl blanks are a new and popular product being sold through some wood turning supply vendors. Segmented pen blanks and even segmented pepper/salt mill blanks have been commercially available for some time now, but the segmented bowl blanks are a relative newcomer in commercial space. I came across a few of them on the website of a vendor that is relatively new to me, WoodTurningz. The price was reasonable and they had some other items I was interested in, so I decided to give a couple of them a try. For my first try with commercially prepared segmented blanks, I decided to go with a mixture of eastern Black Walnut (Juglans nigra) and Hard Maple (Acer saccharum). I have written about these woods extensively in the last two previous posts.
Past and Present Segmented Blanks
I have worked with segmented bowl blanks before but that was one that consisted of many small pieces from many different species, scraps essentially, that included voids and lots of epoxy visible throughout the blank. Those blanks are no longer sold commercially, but slightly similar blanks are available through WoodTurningz, although these blanks are composed of larger, but still varied, pieces. This blank, by contrast, was finely made and there is no visible glue or epoxy at all. There are six small thin pieces of Hard Maple and seven pieces of Black Walnut, four fairly large and three small and thin glued together to make the pattern. I did find it interesting that one of the larger pieces of Black Walnut was considerably more purplish in coloration than the other pieces, indicating that the pieces most likely did not come from the same tree or source.
Most often these blanks are constructed of two woods with highly contrasting coloration. Hard Maple is a commonly used wood because of its consistently pale color and ready availability at a reasonable price. Obviously, Black Walnut is a good choice for a darker wood but I have also seen Paduak and Purpleheart used as well, both woods with distinct coloration that provides high contrast to a wood like Hard Maple while still being reasonably priced and readily available in the American marketplace.
How To Make A Segmented Bowl Blank
I have read about, and seen video of, the making of these types of blanks, and provided that you have the correct equipment it wouldn’t likely be difficult to do. Once the wood is obtained, a sharp saw such as a miter or table saw is used to cut the pieces, which have been measured out to provide the specific design desired. Some segmented blanks are arranged like a butcher block, with all pieces evenly sized, while others, such as this, further play on the contrast between the woods by using different sized pieces to create a pleasing pattern.
Once the pieces are cut, it is absolutely essential to run the pieces through a jointer to ensure absolutely even and flat sides. Without perfectly smooth and flat sides the blank is likely to either fail completely or be esthetically unpleasing. The now smooth and flat sides are glued with wood glue or epoxy, thinly spread, and then firmly clamped together with wood clamps for the drying time, which is dependent on the adhesive used.
Once the adhesive is completely dry the entire blank is usually re-cut to perfect square in case any of the pieces were not sized exactly. Then, the blank is run through a planer to remove excess glue and ensure completely flat surfaces. The blank may also be run through a jointer again to also removed excess glue and again ensure completely flat and smooth sides. These re-cutting, planing and jointing operations are probably not truly necessary because the bowl blank will be cut to round anyway before work begins, so any imperfections associated with glue drips or not absolutely perfectly square and flat sides would be rendered unimportant. However, for sheer visual appeal to the buyer, these steps are common performed by manufacturers prior to sale.
While I think making these blanks would be relatively easy, I don’t think that most wood turners, or at least not those who fairly exclusively do lathe work, like myself, are likely to have a jointer. Unfortunately, I just can’t imagine that it would be reasonably possible to achieve the level of smooth and flat surface required for gluing together blanks of this sort without first jointing the edges.
About the Blank I Turned and How I Did It
In my blank, the Black Walnut was of a nice even coloration although one piece was distinctly more purple than the others. There was no figure in the Black Walnut but it was still attractive and fine wood. There were, however, some small areas of figure in the small pieces of Hard Maple if one looks closely and knows what to look for. When combined, I thought the blank looked quite nice even if it was relatively small at no more than 6x6x3 inches. I would like, in the future, to have bigger segmented blanks to work with.
The segmented blank was mounted and turned as is standard for any bowl blank. I turned to round between centers and then mounted a face plate. Because this was a segmented blank it didn’t matter which side of the blank would become the top or the bottom, but in more traditional blanks I try to make the outside of the wood, as oriented during growth, the top of the bowl, so that would be where the face plate would be mounted. The blank was again turned to round to compensate for any slight shifting upon the application of the face plate and the divot for the Nova chuck was cut. I then turned and finished the bottom, including through 800 grit sand paper. The blank was reversed and mounted on the Nova chuck for the cutting of the interior. Once that was completed the piece was again sanded down to 800 grit.
The blank cut and sanded beautifully with Easy Wood Tools and Abranet. While it is true that Hard Maple is a bit harder than Black Walnut, the differences in hardness are not stark and both woods cut quite nicely, although the open porosity of Black Walnut almost always means that there is more end grain to contend with then in the very closed grain Hard Maple. However, both woods cut evenly and nicely with none of the cutting or sanding problems associated with woods of wildly different densities and hardness as in the segmented bowls made of many small pieces of various species.
For a finish, I chose to use Watco Danish Oil in Natural. I always use Watco Danish Oil with Walnut, of any species, because the oil doesn’t darken the natural color of the walnut in any considerable way and instead allows the natural beauty of the wood to shine through. Also, the open pores of Black Walnut were able to soak up the finish, which will harden over time both in and on the wood, providing excellent beauty and protection in an easy to apply finish. Hard Maple is fairly impervious to most any finish, so while it didn’t soak in much, if at all, it dried smooth and relatively clear on the Hard Maple without any tackiness. I wouldn’t likely use Watco Danish Oil on blank that was entirely Hard Maple, but for this segmented piece, that is mostly Black Walnut, it worked beautifully.
Overall, I was quite pleased with the experience of working with this commercially prepared segmented blank. It was easy to work with, easy to sand, and easy to finish. I greatly enjoy the unusual and striking visual appearance and appeal of the finished piece and my only regret is that the manufacturer doesn’t make blanks of this type in a larger, say up to 12x12x3 inch, size format. If they ever do and I can find one, I am quite likely to choose to buy it and enjoy turning it. I would encourage any wood turner to try out a segmented bowl blank of this type sometime soon.