Welcome back. I'd like to begin this second installment in this series of blog posts on tinsmithing with Bill McMillen with a bit of information about the tin canister and the tinplate and patterns from which it is made.
Almost all tinplate in early to mid 19th century America was imported from the United Kingdom, and in particular from Wales. A detailed history of the development of the tinplate industry in Europe and the US was published in 1915 by D. E. Dunbar, titled The Tin-Plate Industry: a comparative study of its growth in the United States and in Wales. A link to it was given in Part 1 of this blog. Another excellent source of information that is available online for free was published in 1880 in London by Philip William Flower and is titled A History of the Trade in Tin, and it can be accessed through this link.
Bill's Canister is a standard quart and a half size and it makes efficient use of one standard 10" x 14" piece of tinplate. Here is an example of one such piece:
Standard 10" x 14" tin plate
This was perhaps the most common size of tinplate, and tinsmiths would have tried to use it in the most efficient manner to minimize waste. In the case of our canister, one half of the plate, or a 5 " x 14" piece constitutes the body of the cylinder and the other pieces, including a flat round bottom, a cone-shaped piece constituting the neck of the cylinder, and the several pieces that make up the mouth were all made from the remaining 1/2 sheet. The pattern pieces that were used to assemble the piece are shown in the photo at the beginning of this blog. A tinsmith would have patterns such as these prepared for many of the articles and he or she produced on a regular basis. They enabled the smith to quickly trace the pattern onto a new piece of tin and then cut out the individual parts without having to "reinvent the wheel" by redrawing each piece every time a particular article was needed.
Vosburgh's The Tinsmith's Helper and Pattern Book, published in 1912, and referenced in Part 1 of this blog, contains a chart showing the various types of tin ware available: Vosburgh chart of tinplate. In this chart, the standard 10" x 14" is shown in the column headed IC (or "1 common") in the top row titled "trade name." According to this chart, a box of this weight and size of tin contained 225 sheets and weighed 107 pounds. The tin was supplied in wooden boxes made, I believe, from elm. And of course it almost certainly came from Wales, at least until the latter part of the 19th century.
Bill McMillen's first step in constructing this canister consisted of separating the various patterns from their wire hanger. You'll notice on the photo at the top of this installment that each piece has a small punched hole. This allows all the patterns for a particular piece to be kept together on a wire to prevent any from being misplaced. Bill then placed the 10" x 14" piece of tin onto a non-abrasive piece of material to prevent unnecessary scratches that might be visible on the finished piece. The largest piece of the patterns for the canister is the one for the body itself, taking up almost one full half of the whole sheet, and he placed this pattern first on top of the sheet and traced the outline of the pattern onto the underlying sheet using a scratch awl.
Scribing the canister body pattern onto the full sheet using a scratch awl
This awl is made from iron, and most of them have a twist in the center to aid in holding it securely, along with one or two sharp ends that are used to produce narrow scratches on the plate where cuts will be made with tinsnips. The particular awl that Bill is using here has a hook at the top so that it can be hung in a known location and not misplaced (I'm particularly attuned to this attribute because I'm constantly hunting around for things that I've misplaced!) The scratches on the underlying sheet will be followed in cutting the piece for the new canister out of the full sheet. Bill did this by hand using tinsnips as he works primarily with earlier technology.
Using shears (snips) to separate body pattern from the full sheet
Tinsmiths working with techniques common in the mid to late 19th century might use a bench shear to cut straight lines such as this. Most curved lines were cut using hand shears (tinsnips), even later on in the 19th century, although machines or shears capable of cutting curved lines did exist. Snips came in a wide variety of sizes and also in shapes. Here are two that Bill uses. Note the scratch awl on the upper right:
Two old style shears that Bill uses
Now that the piece for the body, representing almost 1/2 of the full sheet has been cut away, the remaining pattern pieces are positioned onto the remaining half of the full sheet so as to most efficiently use the materials.
Positioning remaining pattern pieces onto remaining half of sheet
Bill then traces these patterns onto the sheet using his scratch awl, and cuts the sheet into multiple pieces using hand shears, avoiding cutting along any of the scribe lines. Each piece needs to be individually trimmed to the scribe lines by hand once the section of tin on which it has been scribed is cut away from the full sheet. Note that the pattern on the lower right is rectangular. This pattern will actually be scribed onto the sheet twice, one for the top rim of the canister, and another for the rim of the lid that will encircle the top rim of the canister when the top is in place. These rectangular pieces are fairly easy to cut by hand using tinsnips. Note, however, that several of the pattern pieces have curved edges. The pattern for the bottom of the canister is a circle, and another one for the shoulder of the canister has one concave and one convex edge. These must be cut carefully so as not to warp them. Bill carefully cuts away the excess tin from around each curved edge without actually contacting the scribed line. Once this has been done, he then carefully cuts along the scribed line and the waste piece curves and twists away from the blades of the shear, while the desired piece is not warped.
Excess tin has been cut away close to the scribe lines
Excess material trimmed away; ready for final trim
Trimming along the scribed lines to produce the desired piece:
Final trim of the bottom
Bill did not cut out all of the pieces at once before proceeding to shape any of the canister. Instead he worked to assemble the first two pieces, the cylindrical body secured by a lap joint, and then the bottom with an upward burred edge that slips over the bottom of the body cylinder. Other pieces will be cut and trimmed after the first two pieces have been assembled. This allows for more flexibility as the process of hand making the piece continues. Depending on how the assembly of the cylindrical body with the round bottom turns out, subtle changes can be made to subsequent piece dimensions to ensure tight fits at all joints.
As I just mentioned, the body piece of the canister will be formed into a cylinder with a simple soldered lap joint along its short edge. Before the cylinder is formed a line is inscribed along one short edge of the piece to show the depth of the intended lap. Bill uses a tin gauge with pre-cut notches of known depth to scribe the appropriate line. In this case, the line is inscribed 9/64ths of an inch in from the edge. The pattern pieces have been produced to fit on the resulting cylinder. If you were to change the width of the lap joint, for instance making the scribed line closer to the edge, then the resulting cylinder would have a larger diameter and the round bottom piece would need a narrower burr in order to slip over the bottom of the cylinder body.
Scribing the burr line:
Scribing line for lap joint using gauge
The piece for the bottom disc and the rectangular piece for the body are now ready for assembly. I'm going to close Part 2 at this point. The next installment will begin to describe the various steps in the forming, joining and soldering of the canister. But to keep us oriented, here's a sneak peek at what we're aiming for:
The completed McMillen canister: this will be the end result
I'll be back soon with more.........
If you'd like to read other installments in this series you can read them here.