Commercial Segmented Bowl Blank
Some years ago, I had occasion to purchase some segmented bowl blanks from Penn State Industries. While this is not a vendor that I use routinely since I am not enamored of their shipping practices, I have on occasion purchased something from them that was unique. These segmented blanks, no longer available for purchase, were such a unique item.
The blanks were made by hand in the Philippines from small scrap pieces recovered from the processing of tropical hardwoods harvested either in the Philippine Islands themselves, or imported from neighboring countries for additional processing and shipping. The process of making these blanks must be labor intensive but it does represent a responsible and environmentally sound use of materials that would otherwise be considered and treated as waste material. The small pieces were epoxied together. Depending on what epoxy was used and how its waste is disposed of, the environmental benefit of using the waste wood might be compromised, but at least the intent was good. The segments were then sandwiched between thin sheets of cheap plywood material and compressed. I suspect that much larger blocks were created and then individual blanks cut from this larger block, but this is simply speculation.
Wood Species in the Blank
With the exception of paduak, which is obvious based on appearance and the distinctive sweet bubble-gum smell when turning it, it is not possible for me to identify which wood species were used to make this blank or others like it. I am guessing, again based on unique appearance and geographical location, that some pieces are black palm wood. But beyond the one certainty and the one really good guess, I have no idea what was used. Perhaps a specialist in tropical lumber could identify most, if not all, of the samples, but I am not sure there would be great value in the exercise.
Challenges in Turning
The blank presents some obvious challenges for the turner. The differing textures, porosities, and hardness of the woods used means that the character of the blank is constantly and rapidly changing. Also, the pieces are not perfectly mated and voids occur regularly, some of which are filled with epoxy, again a different hardness and texture itself, and some voids remain completely empty. This increases the likelihood of catches exponentially! The only solution is to be patient and as careful as possible while turning. I encountered no disasters with the piece. I have had experience with this material before and therefore knew some of what to expect.
Challenges in Sanding
Sanding the blank is an additional interesting challenge for the very same reasons as stated above. The different woods respond differently to sanding, some smooth easily, some are more difficult, the epoxy responds in its own unique ways, and the voids can catch the sanding discs. Finally, it is critical to very thoroughly use compressed air to blow away any and all dust which tends to collect in the voids while sanding prior to considering a finish process.
Finishing This Unique Piece
Because some of the woods were porous, and some not, and because of the voids, which I was certain would trap unsightly amounts of any wax or shellac based finish, I chose to use smooth flowing liquid polyurethane with a gloss finish produced by Minwax. It is also available in a matte finish. It is intended for use on materials such as decks and railings that will be exposed to weather, although it is also listed for furniture. It certainly isn’t food safe and the piece won’t be exposed to harsh use, but it was, I feel, the best choice for the unique circumstances. I applied three coats, with at least an hour drying time in between each coat and a light steel wool application between coats as well. If desired, one can use steel wool on the last layer, but this will de-gloss the finish, and I wanted a gloss effect. One problem the various woods introduced in the finish process was that different woods respond differently to the finish. Some took a gloss easily while other pieces, most notably the pale piece in the center of the inside bottom, didn’t take the finish at all, apparently, and seem to be unfinished despite multiple direct applications. But, this is part of the expected unique aspect of using such a blank and the final user will hopefully be aware of these unique circumstances and will value the piece the more for it instead of being critical.
Overall I am pleased with the outcome of working again with this type of blank. It is truly unique and not like any other material I have ever worked with or even seen. I am slightly saddened that these blanks are no longer available, but it does make the pieces I produce with the ones I have even more unique and special than they already are.