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Not many people know this, but this chair (which I own a reproduction of) was directly inspired by plywood whiskey barrels. (I qualify this assertion because it looks like its made from cut cross sections of plywood whiskey barrels)
I finally tracked down the IRS internal communication on aging whiskey for four years in plywood barrels [PDF] from 1950. There is still an eight year update that I haven’t been able to locate but I’m working on that. The four year paper was very tricky to find. It had a WorldCat entry unlike many of the other IRS internal communications, but it generated an error that could not locate the library that held the record. The trick was to contact WorldCat via their tool for correcting database errors. (I might have pretended to be my local library) and I asked them: if no library is listed as the record holder then who created the record in the first place?
I assumed the creator of the record would be the record holder. This information is not publicly displayed and WorldCat revealed the library to be the Forest Products Research Laboratory library which is a U.S. government organization. The library claimed they could not help non-employees but they were able to be sweet talked (saying #whiskey gets you really far these days!). Besides digitizing the paper, these wonderful people even went through the card catalog and gave me some great related citations to pursue down the road. It turns out a nice amount of work has been done on barrels made from veneers.
I have mentioned the plywood whiskey paper before and included drawings from a 1944 patent application to help people visualize the process of making the barrels (I have been assembling a team to produce some of the barrels!)
The paper is interesting and its scope is far more extensive than I would have guessed. The barrels of three different manufacturers were distributed among 13 participating distilleries for a total of 40 different plywood aged whiskeys. Two manufacturers used only oak while one manufacturer used a combination of oak and maple.
The results of the study are fairly easy to follow, but are not necessarily encouraging for the use of plywood barrels to create products resembling Bourbon which traditionally relies on the highest quality first use barrels. The manufacturer using maple produced significantly inferior results to the other two which used only oak and the 100% oak plywood barrels still produced much lighter and thus inferior results compared to staves. The problem might be the sourcing within the tree for the oak. If the veneers have to be the same quality as a stave, then why not just stick to staves?
The results do not nullify the use of plywood barrels. They just can’t be intended for first use scenarios like Bourbon but rather might be suitable for rum or gins perhaps with interesting aromatic veneers such as cedar. One issue the paper mentions is the adhesives used to affix the veneers. Leaching into the spirit was not a problem, but rather the issue was creating too much of an impermeable layer for the barrel to breath through sort of like how some barrels are lined with paraffin wax first (often grappa). Adhesion could probably be reconsidered with modern inert options and the possibility of creating channels of permeability so barrel breathing can be maximized.
If you want to get in on our test run of plywood barrels, please shoot me an email with your intended use, your concerns, your ideas, or anything relevant that is on your mind.