The Modern Equivalent & Cheatsheet

You already own the machine that made this one obsolete. This closing volume is the practical payoff: how you would actually reproduce a gunstock in your shop today, where a cheap middle path fits, whether building a Blanchard-principle copier is worth your bench time, and a laminate-ready cheatsheet that compresses the whole series onto one page.

9.1 The CNC Route — What Modern Stock-Makers Actually Do

The direct modern descendant of the Blanchard operation is a 4-axis (rotary A-axis) CNC setup, and it mirrors the original’s kinematics almost one-to-one: the workpiece rotates while a cutter traverses its length, except the “master” is now a digital model instead of an iron pattern. The workflow:

1. Get the model. Either 3D-scan a donor/reference stock (photogrammetry or a hobby-grade structured-light/laser scanner) or model one from scratch in CAD (Fusion 360 or equivalent). The digital model is Blanchard’s iron master — with the enormous advantage that you can copy, edit, and version it freely, which is the single biggest thing the original could not do.
2. Fixture on the 4th axis. Mount the blank between a rotary indexer (A-axis) and a tailstock so the CAM system can rotate it under the cutter — exactly the rotating-work geometry of the original.
3. Rough with a ballnose or bull-nose end mill, stepping down in Z and indexing in A. Irregular organic 3D forms like a stock rough well with a ballnose and a rotary/parallel strategy; this is your roughing pass, and it is the analog of Blanchard’s single roughing traverse.
4. Finish with a smaller ballnose to bring the scallop height down, then hand-sand to close the last bit. This is the same “machine to near-net, hand-finish the surface” division of labor the Blanchard line ran — just with vastly better as-cut tolerance and a far smaller finishing burden.

This is not theoretical: it is what real manufacturers do. Both McMillan and Boyds run CNC inletting/profiling programs keyed to specific action/barrel/stock combinations with a technician overseeing the cut.¹² The router-with-4th-axis is the most direct, practical path for a one-off “Blanchard-style” duplication in a shop like yours; a mill would also work, but a router’s work envelope and speed usually suit wood better.

9.2 The Cheap Middle Path — Router Pantograph Duplicators

Between the CNC route and building your own machine sits a genuinely useful commercial tool: the router-based pantograph gunstock duplicator, e.g. the Gemini Universal / Gunstock Carver. It is a router-mounted rotary-fixture duplicator sized for gunstocks: a stylus/pattern-follower traces a master stock and guides a hand-fed router bit (roughly a 1¾-hp router, 3/4” carbide bit) over the blank, working in birch, maple, walnut, or laminate.³ Mechanically it is a true pantograph linkage rather than Blanchard’s swing frame, but in spirit it is the same trace-and-copy concept, and it is the direct commercial descendant of the idea. If you want to copy an existing stock without touching CAD, this is the low-friction option — cheaper than tooling up a CNC job for a single copy, and hands-on in a way some builders prefer.

9.3 Should You Build an Actual Blanchard-Principle Copier?

Straight answer: yes as a historical demonstrator, no as a production method.

The mechanism is genuinely approachable for your shop — two same-diameter wheels on a common pivoted arm, a means to synchronize model and blank rotation (shared shaft with belts or a timing arrangement), and a traversing carriage. The wheels, arm, bearings, and carriage are all mill-and-router work; nothing about it needs a capability you lack. As a working scale/historical recreation it would be a rewarding, instructive build and a great demonstration of why the thing works — which is squarely in the spirit of a deep dive about how machines functioned.

But be honest about the purpose. Against the CNC router and pantograph duplicator you already have (or can buy cheaply), a home-built Blanchard copier would be strictly worse for actually producing a stock: worse tolerance, worse finish, one physical master per design, an unguarded high-speed cutter to engineer around, and no ability to change the design without re-cutting the master. Build it because it is a beautiful mechanism you want to understand with your hands — not because it will make you a better stock than the machines that replaced it. Frame the project as “a working historical demonstrator,” and it is a great idea; frame it as “my new stock-making method,” and it is not.

9.4 Cheatsheet — The Whole Series on One Page

Timeline

Table 1 — Timeline

Date	Event
1788	Thomas Blanchard born, Sutton, MA
~1806-1817	Tack machine (patent X0003010, 1817); dates conflict, unresolved
~1817-1818	Gun-barrel lathe for Asa Waters, Millbury MA
~1818	Gunstock lathe conceived/prototyped (reported, not certain)
1819-09-06	Patent X3,131, “Turning Irregular Forms,” granted (Millbury, MA)
1820-01-20	Patent withdrawn and reissued by act of Congress
~1822	Surviving/refined example built (the machine at Springfield NHS)
1834	Congressional patent extension (well-attested)
1840 or 1848	Further extension(s) — reported inconsistently; not resolved
1851-52	Bessey’s guidebook: 14 machines, 20 men in the stocking room
1864	Blanchard dies, Springfield MA
1998	Reinhart Fajen (first CNC gunstocks) suspends manufacturing — the type is gone

Spec / fact table

Table 2 — Spec / fact table

Item	Value	Confidence
Patent	US X3,131, “Turning Irregular Forms”	Verified
Granted	1819-09-06, to Thomas Blanchard of Millbury, MA	Verified
Patent status	Restored pre-1836 X-patent (Patent Office fire, Dec 15 1836)	Verified
Copy ratio	1:1	Inferred from mechanism, not directly sourced
Machine type	Copying “lathe” — technically a shaper (rotating cutter)	Verified (NPS)
Stocking line	14 machines (lathe + 13), 20 men	Verified, two sources
Royalty	9¢ per gunstock, to Blanchard, at Springfield & Harpers Ferry	Verified (Iles)
What the lathe cut	Exterior profile only; inletting done by separate machines	Verified
Surface left	Rippled/faceted; hand-finished with scrapers & sandpaper	Verified (NPS)
Drive	Water power → line shaft → belts	Verified
Feeds/speeds/DOC	Unknown — no source found; not invented here	Gap
Surviving original	Springfield Armory NHS, 1822, SPAR 5550, ~2.5 m	Verified
Build year 1818/1819/1822	Conflicting; 1819 = patent, 1822 = survivor	Flagged

Do NOT confuse with: the Blanchard grinder — a vertical-spindle rotary surface grinder by Winslow Blanchard (Blanchard Machine Co.), first built 1909, still in production use. Different machine, different man, coincidental surname.

Source URLs

• Patent record (DATAMP): https://www.datamp.org/patents/displayPatent.php?pn=X3131&id=5435
• NPS, “Thomas Blanchard and His Lathe”: https://www.nps.gov/spar/learn/historyculture/thomas-blanchard-and-his-lathe.htm
• NPS, “Woodworking at Springfield Armory”: https://www.nps.gov/spar/learn/historyculture/sa-woodworking.htm
• National Inventors Hall of Fame: https://www.invent.org/inductees/thomas-blanchard
• Iles, Leading American Inventors (1912): https://todayinsci.com/B/Blanchard_Thomas/BlanchardThomas-LeadingAmInv.htm
• Gemini Gunstock Carver (router duplicator): https://www.wood-carver.com/gunstock.html
• Best modern scholarly source (un-fetched): Carolyn C. Cooper, Shaping Invention — via https://muse.jhu.edu/article/888479/summary

9.5 Bibliography

Footnotes

1. McMillan Fiberglass Stocks, CNC inletting process (search-synthesized). ↩

2. Boyds Hardwood Gunstocks, company history. https://www.boydsgunstocks.com/content/resource-center/about-boyds ↩

3. wood-carver.com, “Gunstock Carving and Duplication” (Gemini Universal/Gunstock Carver). https://www.wood-carver.com/gunstock.html ↩