ATF's Gorton 3-B Pantograph

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1. Solid Brass Plate Working Pattern Method

In the 1941-1948 period, ATF temporarily abandoned the wax plate methods of working pattern production that it had used since 1905 and adopted a method of cutting working patterns out of brass plate using an industrial pantograph. [1] This method is the one documented in ATF's 1948 film Type Speaks! [2]

See also the Chronology of ATF's Methods.

2. Identifying the ATF Gorton 3-B

This machine is illustrated in use in a 1945 photograph by ATF reprinted in Rehak's Practical Typecasting. A right-reading drawing is being used to engrave a right-reading intaglio working pattern at a reduction of about 3:1 (just eyeballing it). The operator is shown tracing the drawing freehand, without a french curve in sight. Rehak identifies this machine as a Gorton "#3-U engraver," but this is not correct (see below).

It was also shown in Type Speaks! Here are three frames of it from that film:

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Other shots in the film show the pattern blank being mounted and the engraving process itself. As with the still photograph in Rehak, a right-reading finished drawing is traced freehand to produce a right-reading intaglio pattern.

I'm not at all sure I believe that they did this freehand, but if in fact this was "just for publicity shots" and they did use straightedges and French curves in regular practice, [3] I don't understand why they hid them. While there is a tradition of type designers scoffing at the "French curve men" of the drawing office, French curves are shown in use in the drawing office in the scene just prior to this one in Type Speaks!

The machine shown in these ATF sources is a George Gorton Company model 3-B three-dimensional pantograph engraving machine stripped of most of its three-dimensional apparatus and used as a two-dimensional machine. Here is a 3-B as shown in the Gorton company's 1950 pantograph manual: [4] [5]

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Rehak refers to the ATF machine as a "#3-U," but it is not. The 3-U is a much lighter machine which is based around the Taylor-Hobson system of separating the support of the cutting spindle from the pantograph mechanism itself (in a heavy-duty machine such as the 3-B, the pantograph supports the cutting spindle directly). Here is a photograph of a 3-U from the Gorton literature. [6] It is clearly quite unlike the ATF machine.

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Gorton's pantograph designs evolved into a quite rational lineup of multiple ranges of machines produced in multiple sizes. So in the 1930s and 1940s the produced a few small and/or special models, a mid-range series of two-dimensional models (the 3-U and the larger 3-Z), and a heavy range of three-dimensional machines (the 3-B and the larger 3-L). [7] To securely identify the ATF pantograph as a 3-B, we need to look at its big brother, the 3-L: [4]

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This is not the same machine shown at ATF. In particular, look at the way in which the top of the main machine casting on the 3-B (and the ATF machine) expands to the left to accomodate the ratiobar mechanism while the equivalent part of the larger 3-L is straight.

3. Notes

1. See Rehak, Theo. Rehak, Theo Practical Typecasting. (New Castle, DE: Oak Knoll Books, 1993) , p. 133.

2. American Type Founders. Type Speaks! Elizabeth, NJ: American Type Founders Sales Co., 1948.

3. Just a few years later, The Monotype Corp. Ltd. showed their pantograph operators using straightedges and French curves (in a wax plate method). See 'Making Sure' At the Monotype Works: Type Faces In the Making (The Monotype Corp. Ltd., 1956)

4. Pantograph Instruction Book and Parts Catalog: For All Pantograph Engraving Machines (Racine, WI: George Gorton Machine Co., 1950) This is also Gorton Form 1385-E.

5. The three-dimensional apparatus is based around the prominant horizontal bar lightened with circular cutouts which appears near the top of the machine in the Gorton photograph. This has been removed in the ATF machine. Gorton employed the trade name "ratiobar" for their three-dimensional mechanism. Other pantographs achieved three-dimensional movement by pivoting the entire pantograph mechanism. This results in some parallax error, of course. (My 1960s vintage Deckel GK-21, a fine machine, is built in this manner.) The Gorton mechanism is more sophisticated: both the tracing spindle and the cutting spindle move vertically in their mountings, and their vertical motion relative to each other is controlled by the perforated "ratiobar." None of this is necessary for engraving two-dimensional working patterns, of course.

6. Pantograph Instruction Book and Parts Catalog: For All Pantograph Engraving Machines (Racine, WI: George Gorton Machine Co., 1935) This is also Gorton Form 1385 [no letter suffix; this is the original edition].

7. Gorton machine numbers in the 1930s and 1940s are very confusing. In addition to the machines noted, they also produced the 3-F (a small-capacity version of the 3-U), the "Large Gap 3-U," the magnificent 3-K Precision Matrix Machine, and the 3-S Die Cutting and Profiling Machine. Note that the '3' in these designations does not mean 3-dimensional.

In the 1950s they rationalized much of this with a system of designations of the "Pm-n" format. They also re-engineered the machines to be much heavier. 'P' meant pantomill (by then their pantograph engravers were heavy enough to be considered milling machines). The 'm' was the size within the range. The '-n' was 1 or 2 for 1-dimensional or 2-dimensional. So the very common 3-U became the P1-2 (that is, the smallest 2-dimensional machine), while the 3-Z became the P2-2 (a really hefty P3-2 was later introduced). In the 3-dimensional lineup, the 3-B didn't have an exact successor (the P1-3 differed substantially from it). The 3-L evolved, more or less, into the P2-3.

To simplify all of this for the practical matrix maker:

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