The Stanley No. 4 is the most widespread and best-known metal smoothing plane in the history of woodworking. It was made for over a century with essentially the same core design, which makes it the ideal model for showing how Stanley's planes evolved. Collectors and restorers rely on the type study: a system of 20 manufacturing "types" from 1867 to 1967, where each type is identified by small production details.
For orientation: length about 9″ (≈ 230 mm), iron width 2″ (≈ 50 mm), weight around 1.7 kg (≈ 3¾ lb). Cast-iron body, early brass hardware, and a rosewood tote and knob.
How the type study works — and its limits
The type study dates a plane by construction details, not by a serial number. The type number (1–20) refers to a manufacturing generation, not to the model. A few things worth knowing before you pin down an exact year:
- The study is most accurate for the No. 4. For other sizes (and for Bedrock or transitional planes) it is only a rough guide.
- Harlequins. Many old planes are assembled from parts of different years. Date by the body (bottom casting); it changed the least.
- Changes overlapped. Stanley used up old parts stock, so transitional pieces combine features of two types. The war years (Type 17) are especially chaotic here.
- Date by a combination of features, not a single detail.
Quick tells
The checkpoints worth looking at first:
- Patent dates cast behind the frog: none → Type 1–8;
Mar-25-02 / Aug-19-02→ from Type 9;APR-19-10added → from Type 11;APR-19-10alone → Type 13; no patent info on the casting → Type 15 and later. - Lateral adjustment lever: first on Type 5. One-piece straight = Type 5; two-piece with a disc = Type 6 onward.
- Knob: the high knob arrives at Type 12; the raised receiving ring under the knob from Type 14.
- Frog adjustment screw: from Type 10.
- Hole in the lever cap: symmetrical "keyhole" up to Type 15; kidney-shaped from Type 16.
- Body finish: black japanning for over a century; blue paint only from Type 20.
Overview of Types 1–20
| Type | Period | Main identifying feature |
|---|---|---|
| 1 | 1867–1869 | Boston; balloon knob; "L. BAILEY'S PATENT" |
| 2 | 1869–1872 | Stanley; rectangular lever-cap spring |
| 3 | 1872–1873 | fragile reduced frog on a vertical rib |
| 4 | 1874–1884 | return of the robust frog; foundry number in the seat |
| 5 | 1885–1888 | debut of the lateral lever (one-piece, straight) |
| 6 | 1888–1892 | lateral lever with disc; round iron hole near the edge |
| 7 | 1893–1899 | spaced-out "No 4"; "S" in the casting |
| 8 | 1899–1902 | "B" in the casting; single date 7-24-88 |
| 9 | 1902–1907 | first patents behind the frog; "BAILEY" at the toe |
| 10 | 1907–1909 | frog adjustment screw |
| 11 | 1910–1918 | APR-19-10 added; V-shaped logo |
| 12 | 1919–1924 | high knob; sweetheart logo |
| 13 | 1925–1928 | APR-19-10 only; STANLEY on the lever cap |
| 14 | 1929–1930 | "MADE IN U.S.A." at the toe; ring under the knob |
| 15 | 1931–1932 | no patents; "BAILEY" and number swapped |
| 16 | 1933–1941 | kidney-shaped lever-cap hole; ogee frog |
| 17 | 1942–1945 | war production — variable, often substitutes |
| 18 | 1946–1947 | brass returns; lighter castings |
| 19 | 1948–1961 | Y-shaped frog seat; rosewood returns |
| 20 | 1962–1967 | blue body; pressed steel; end of the era |
Early types (1–4)
No patent dates behind the frog, scarce. Type 1 was still made in Boston (balloon knob, "L. BAILEY'S PATENT DEC. 24, 1867", I-shaped frog seat). Type 2 is already under Stanley. Type 3 is a short-lived, fragile frog on a vertical rib — often cracked. Type 4 brings back the robust frog and a broad rectangular seat.
Golden types (5–15)
The best balance for users and collectors alike. Type 5 debuts the lateral lever (one-piece, straight). Type 6 doubles the lever with a disc and moves the round iron hole toward the edge. Type 9 first casts patents behind the frog and "BAILEY" at the toe. Type 10 adds the frog adjustment screw. Type 11 is a widespread, well-liked user type. Type 12 introduces the high knob and the sweetheart logo. Type 14 adds the ring against knob splitting.
Later types (16–20)
Excellent tools, less sought by collectors. Type 16 introduces the kidney-shaped lever-cap hole and the ogee frog — pre-war quality. Type 17 is the hardest-to-date war production with substitute materials. Type 19 is recognised by its Y-shaped frog seat and the return of rosewood. Type 20 gets a blue body and cheaper pressed parts — the end of the classic era.
Rarity and value
The No. 4 was made in enormous numbers, so the vast majority of examples are common and inexpensive. The scarce ones are mainly the early types and pristine pre-war pieces.
- Scarce / collectible: Types 1–4 (especially 1–3), fine sweetheart pieces in top condition.
- Best quality-to-availability: Types 11–16 — a full lateral lever, good machining, rosewood, and still easy to find.
- Common but excellent tools: Types 18, 19.
- Least sought by collectors: Type 17 (war substitutes) and Type 20 (cheapened parts).
Rough values: user-grade around US$35–90, a nice pre-war piece US$60–125, early types in the hundreds. Value is raised by a low type number, rosewood, surviving japanning, an original iron, and the condition of the frog and sole.
A few extra notes
- English production. Stanley also made the No. 4 in the UK. The American type study does not apply to those; they are dated differently and are generally less prized by collectors — but they are usually fine as users.
- Corrugated sole (4C). Rather an exception on the No. 4; beware of later-cut grooves (originals should be parallel, sharp, evenly deep, and stop before the mouth).
- Date by the body. Parts are often mixed across years — what matters is the consistency of patina and wear across body, frog, lever and iron.
Sources: Patrick Leach (Blood & Gore / Hyperkitten type study), John Walter, Wood & Shop, Time Tested Tools.