Scrub Plane

identity

• name: Scrub plane — a hand plane for coarse stock removal, commonly short-bodied, with a relatively narrow, strongly cambered (convex-radiused) cutter and a wide-open mouth, used to remove large amounts of stock fast from rough-sawn or misshapen lumber before any truing plane touches the board [SP1][SP6]. Older/regional English alternate names, none in wide modern use: Hunter, Scud/Scudding, Scurf/Scurfing, Cow plane ("a 'cow cut' is an old country term for a radical haircut") [SP1][SP3].
• family / category: Bench planes — the roughing/dimensioning branch. In a modern multi-plane workflow a dedicated scrub may precede a jack/fore and a try/jointer; in traditional English/American practice, a cambered fore or jack commonly combined roughing and preliminary flattening. Continental traditions include shorter dedicated roughing planes. Makers market different sequences, and a user need not own both a scrub and a cambered fore/jack [SP5][SP18].
• one-line: A short, narrow-cutter, strongly cambered roughing plane built to remove stock by the shaving-inch rather than to certify a flat surface; it can bring high spots down under measurement, but it does not leave a reference-ready face [SP1][SP5][SP6].
• naming note — genuinely contested, not settled: a forum assertion (Warren Mickley, Sawmill Creek) holds that the term "scrub plane" entered English around 1890, with "Stanley developed the plane for carpenters. The jack plane was the traditional roughing plane in the English and American shops" [SP2]. That is an attributed hypothesis, not a dated-dictionary finding. Paul Sellers asserts the underlying tool predates Stanley's metal version by a long margin [SP3] but offers no primary citation, so it is his assertion. A German-origin theory for the English name ("Schrupp," as in schrupp das Deck, + Hobel) is reported but unconfirmed against a primary etymological source [see open gaps].

✦ how NOT to use it

• not-for:
  • Work that needs a smooth, straight, glue-ready or reference-flat surface at that stage. Wonkee Donkee: "Because of the scrub plane's length (relatively short compared with jack, fore and jointer planes) it is not suited to straightening up wood, as its short sole is likely to follow any undulations" [SP1]. That describes the lack of automatic long-span registration, not an inability to remove marked high spots.
  • Routine full-width shaving at aggressive projection: force rises sharply, though actual feasibility depends on projection, species, grain, sharpness and shaving width. It is generally undesirable, not physically impossible.
• dangerous: (rebuilt; "no injury account was found" is a research result, not a risk assessment.) A scrub is driven with heavier force than a fine-set smoother and carries a deeply projected cambered edge. Hazards and controls, from Fine Woodworking's hand-plane safety guidance (read this pass [SP25]), the Veritas instructions as relayed by the reviewer, and the reviewer's safety notes:
  • Workholding: secure and support the stock so it cannot rock or slide, with a vise, clamps, bench stop, dogs, wedges or shims appropriate to the work [SP25]. Avoid clamping force that bows the board while you check flatness [manual, relayed].
  • Hands and the mouth: keep hands on the tote and knob or designated grips, and fingers clear of the mouth and cutter, especially while sighting, installing, removing or sharpening the iron; if planing a small piece with the plane upside down, keep fingers clear of the blade [SP25].
  • Sharp, securely clamped cutter: a sharp iron needs less pushing force, so less chance of a slip or sudden run-off [SP25]. Use a cutter clamped as the maker directs.
  • Loose blade handling: the Veritas instructions warn that careless blade handling can cause serious injury [manual, relayed]. Set and remove the iron on a stable wooden surface, and protect hands and feet when handling the loose blade. A reader comment on the Fine Woodworking page advises never sharpening or removing a blade in open-toed shoes, sandals or bare feet, since a falling blade can injure an exposed foot [SP25].
  • Footing, bench height and stroke end: stable footing and a bench height that allows controlled force (Fine Woodworking: with the arm hanging straight, the bench surface level with the fingertips [SP25]). Plan the end of each stroke so hands and plane do not collide with clamps, bench hardware or the unsupported far edge; stop before the plane runs off an unsupported end [manual, relayed].
  • Lever cap and wedge: follow the maker's exact adjustment method. Veritas notes only modest lever-cap torque is needed and that overtightening the knob can damage the plane [manual, relayed]. That is tool damage, not injury; the two are separate risks.
  • Grinding a conversion iron: use the grinder, tool-rest and eye-protection controls for the machine in use, and do not overheat the cutting edge [manual, relayed].
  • Storage: store the plane and blade so the edge cannot cut a hand or be damaged, and do not leave a loose cutter where it can fall [manual, relayed].
  • Material: reclaimed or found stock is gated under matching above.
  • This is AI-derived corpus guidance and does not replace the maker's manual for the exact plane.
• damaging:
  • Using the scrub with the grain rather than diagonally across it on reversing or figured grain causes deep tearout. Walter Egon: working with the grain is possible only "so long as you can live with the atrocious tear-out" [SP9].
  • On a wooden Continental-style scrub, overtightening the wedge is a commonly named mistake, risking a cracked body or misaligned iron [SP9].
  • Hitting embedded metal in reclaimed stock can chip the cutter (see matching).
• beginner-trap:
  • Forcing a full-width shaving. Jim Koepke: "When using my scrub plane, it is seldom if ever set to take a full width shaving... In use my shavings are an inch wide at most" [SP10]. The sagitta values in the Petroski note show why a wide cutter at a tight radius takes an extreme full-chord bite.
  • Confusing a deliberately rough, scalloped result with a failed cut: the scrub is supposed to leave an uneven surface; that is the tool's job, not a mistake [SP1][SP12].
• lineage-misuse:
  • Treating the scrub as the only tool that can flatten, or as unable to contribute at all. The Guidice claim that a scrub is the only tool that can truly flatten a board is wrong because of the word only; practitioners flatten with a cambered jack (Oppenheimer [SP2]; Woodcraft's author [SP24]). The opposite overcorrection, that a scrub cannot participate in flattening, is also wrong: with winding sticks, straightedges and frequent checking it can remove marked high spots and bring a face out of wind, after which a longer plane gives long-range registration. Schwarz found his jack more reliable for truing a face "because of its longer sole" [SP5].
  • Confusing the scrub with the jack plane. The Jack Plane entry: "Jack over-cambered into a scrub (or a scrub under-cambered into a jack) — the scrub is shorter and narrower on purpose... Keep them distinct" [SP18].
  • Confusing the scrub with Stanley's No. 340 furring plane. Both are cast-iron Stanley products for rough surface work, but the No. 340's patent targets floor-smoothing in place [SP8].
  • Converting a plane without thinking it through. A 2-inch versus an 8-inch radius produces radically different projection and effort, and moving a frog or filing a casting is not an equivalent step on every plane. Grinding adds wheel, tool-rest, heat-treatment and edge-handling hazards, and a wide converted body can take more force than a purpose-built narrow scrub. Choose a sound, non-collectible donor; decide whether the goal is a mild fore/jack camber or a true scrub cutter; grind without overheating the edge; confirm the shaving path clears without weakening the sole or frog; keep the cutter securely supported; test at shallow projection on scrap. No universal radius or mouth-filing step is prescribed here (review Fix 12).

correct use

• what it's genuinely good at: removing large amounts of material fast from rough-sawn, cupped, twisted or bowed stock, in short, choppy strokes rather than long continuous passes — Schwarz's tested technique, working at 30° or more to the grain rather than parallel to it [SP5][SP13].
• a modern workflow it fits into: scrub for coarse removal → jack/fore (bridges the scrub's furrows) → try/jointer (trues over length) → smoother if the surface must be finish-ready [SP12][SP13][SP14][SP15][SP18]. This is how current makers describe it, not proof of historical descent or universal shop practice.
• in flattening: a scrub can be used with winding sticks, straightedges and frequent checking to bring high areas into the same plane, but its short sole and deep narrow cut do not reliably certify long-range flatness or leave a reference-ready surface. Follow with a fore/jack/jointer as the work and tolerance require. Woodcraft's flattening guide (read this pass) describes a scrub as "a narrow-bodied plane with a heavily cambered blade designed to remove large scallops of wood," notes some woodworkers use it to remove high spots quickly, and has the author prefer a cambered #5 jack as "a bit too aggressive" a scrub for most purposes; winding sticks are rechecked during planing, and a #6 or #7 with a lightly cambered blade takes the remaining scallops [SP24]. The reviewer reports Popular Woodworking likewise shows a scrub removing marked high spots to bring a board out of wind, and Infinity markets its scrub for removing twist and cup [manual, relayed].
• on stock too wide for a machine: Cohen: even in a shop with a powered jointer/planer, a scrub remains useful on boards wider than the machine's capacity [SP16].
• a legitimate finish choice: Lie-Nielsen's copy names deliberately leaving the scalloped surface as "an interesting textured feature" [SP12]; Veritas sells a texturing blade [SP13].

✦ matching — for the app's read

• does: removes bulk material locally via a strongly cambered, narrow cutter taking deep narrow cuts, typically at 30°+ to the grain; reduces cup, twist and high spots under straightedge and winding-stick control; works toward gauge lines for hand thicknessing; roughs irregular backs or wall-fitting mouldings; can leave deliberate scalloped texture.
• suits: first-pass dimensioning of rough-sawn lumber by hand, ahead of a jack/jointer/smoother; knocking down a cupped or twisted board before finer tools true it; stock wider than a benchtop power jointer/planer can handle; a small or no-power-tool shop's rough pass [SP16].
• reclaimed, found or salvaged stock — a project/material gate, not a footnote. The original entry matched the tool to "reclaimed lumber of unpredictable dimension (firewood-grade stock, salvaged beams)" with no controls. Reclaimed or found stock may contain nails, screws, staples, wire, grit, coatings, lead paint, preservatives, rot or insect damage. Even with a hand plane, hidden metal can chip the cutter, stop the stroke abruptly, damage the work and cause a loss of control; the No. 340's own catalog copy names grit removal as a rough-surface job [SP8]. Before planing reclaimed or found stock: identify its provenance; inspect and scan for embedded metal; remove hardware and surface grit; evaluate coatings and treated wood and biological damage; reject material that cannot be made safe for the intended use. Do not assume "hand tool" means contaminants are harmless, and do not treat "found" or "firewood-grade" as evidence of structural soundness or chemical safety (review Fix 11). The living-tool accounts in the human-side section (salvaged beams, subfloors) are accounts of use, not clearance.
• kit-fit:
  • pairs with: straightedge, winding sticks and a marking gauge; secure bench workholding; then a fore/jack/jointer/smoother or a thickness planer once a safe reference face exists.
  • substitutes for: the local high-spot-removal stage of face preparation, including stock too wide for a machine jointer [SP16]. A cambered fore or jack can often substitute for a dedicated scrub. An electric hand planer used carefully can substitute for scrub-plane slab work [SP22].
  • cannot by itself guarantee: a smooth, glue-ready, straight or dimensionally verified reference face; those need measurement and usually later tools and passes.
• not-for (project-keyed): surfaces that must be smooth, straight, glue-ready or reference-flat at this stage; joinery reference faces or precision edges unless later truing removes the scallops; contaminated or embedded-metal stock until inspected and cleared. It can be used deliberately for a scalloped rustic texture where that surface is the design intent [SP1][SP12][SP13].
• access: controls are simple, but effective use takes reading cup and twist, secure workholding, controlled deep cuts, and sharpening a pronounced camber. The original "no barrier to entry" line is withdrawn. Sharpening the deep camber freehand is named by experienced users as a real skill, more so at scrub radii than at a jack's gentler 8–10" [SP10]. Both views are in the record; neither is settled.
• revival: fast hand-tool stock prep without a jointer or planer [SP16][SP17]; its marketed second life as a texturing tool [SP12]; Cohen's account of visible, rapid material removal [SP16].

anatomy

• the iron — on purpose-built Stanley, Lie-Nielsen and Veritas models, a stout single iron ground to a pronounced convex camber; the current Veritas and Lie-Nielsen patterns are single-iron [manual, relayed]. Camber radius is a load-bearing spec: 1½" on an original Stanley No. 40 (Cohen's measurement), 3" on both the Lie-Nielsen and Veritas remakes [SP12][SP13][SP16]. Blades run heavier than an ordinary bench-plane iron: Cohen measured Stanley bench-plane irons at 1/16"–5/64" versus the No. 40's 1/8"; Lie-Nielsen and Veritas spec 3/16" [SP16][SP12][SP13].
• chipbreaker: common to omit, not universal. Many purpose-built scrub planes, including the current Veritas and Lie-Nielsen patterns, use a single iron without a chipbreaker (Veritas: "This is a single-iron tool, meaning there is no cap iron or chip breaker" [SP13]). Some current wooden scrub planes are available with a double iron: The reviewer reports Ulmia's catalog lists HW5D-33 with a 33 mm double iron and chipbreaker [manual, relayed], and converted jack or smoother planes may keep their cap iron. The defining geometry is the strongly cambered roughing cutter and open shaving path, not a universal absence of a cap iron. The cutter is not "unsupported" without one: the bed, wedge or lever cap, and body still support and clamp it. The original entry's "single clearest anatomical difference from the jack plane" and "confirmed across every maker" are withdrawn.
• the mouth and adjustment — wide open by design. Adjustment varies by model: Lie-Nielsen and Veritas omit a feed adjuster and set the cutter manually (Lie-Nielsen: "Sight down the sole to set the depth of cut — practice will tell you the amount of exposure needed for the job" [SP12]); ECE uses hammer adjustment [SP14]; some current wooden models, including Infinity's, use a Norris-style mechanical depth/lateral adjuster [manual, relayed] [SP15]. Conversions may retain bench-plane hardware.
• body and grip — metal production scrubs (Stanley, Lie-Nielsen, Veritas) carry a front knob and full rear tote; traditional wooden Continental scrubs (ECE's Schrupphobel) use a front horn [SP14]. Open gap: no source found confirms a traditional wooden scrub that historically had no rear handle at all [see open gaps].
• length — short relative to a jack: Stanley No. 40 = 9½"; No. 40½ = 10½"; a No. 5 jack runs 14" [SP6]. A short sole reduces automatic bridging over length, but technique plus external references can still bring a face coplanar (see lineage-misuse).

variations (living)

• Stanley No. 40 / No. 40½ (vintage, 1896–1962 / 1902–1948) — American iron scrub planes; the No. 40½ is scarcer and commands a higher collector price [SP6][SP23]. ("Founding" is dropped: no earlier-product search was documented.)
• Lie-Nielsen No. 40½ — a modern remake of the Stanley 40½: 10¼" long, 1.450" × 3/16" A2 blade at Rc 60–62, 3" camber radius, ductile-iron body, 2.40 lb. Listed as unavailable ("Notify Me When Available") on the maker's site at the time of the original pass [SP12].
• Veritas (Lee Valley) Scrub Plane — made in Canada, 10¾" × 2¼", 3 lb, single iron, 1½" × 3/16" blade at 3" radius, set screws to resist sideways shift on knots; HCS steel or PM-V11; a dedicated texturing blade is sold for the same body [SP13].
• E.C. Emmerich (ECE), Germany — wooden Schrupphobel: red-beech body, hornbeam sole, 33 mm chrome-vanadium blade (Rc 60–62), 9½" long, hammer-adjusted [SP14].
• Ulmia, Germany — wooden scrub planes in commercial production (Cohen); Run 378 confirmed model HW5-33 from a retailer page [SP16]. The reviewer reports the current catalog lists HW5-33/HP5-33 with single irons and HW5D-33 with a 33 mm double iron and chipbreaker [manual, relayed].
• Infinity Tools wooden scrub plane — European-made import: beech body, hornbeam sole, 36 mm chrome-vanadium blade at 58 HRC, a Norris-style depth and lateral/skew adjuster [SP15]. Price and availability are volatile: the original pass recorded $99.90; the review (2026-08-03) saw $79.90 and unavailable [manual, relayed]. Check the maker before relying on either.
• Shop-made / converted scrub planes — a documented DIY tradition, but model-specific, not a recipe. See how NOT to use it for the conversion cautions [SP17][SP10][SP3].
• Stanley No. 340 "furring plane" (1905–1917) — distinct, patented, pitched at floor-smoothing (see lineage) [SP8].

trades

• Cabinetmaking / fine furniture-making — the first station of the hand-tool dimensioning sequence in shops that still dimension by hand [SP5][SP16].
• Carpentry / trim work — Schwarz's reported theory for why Stanley built the No. 40: a worksite tool for trim carpenters dealing with framing and subfloor irregularities [SP4].
• Green woodworking / timber-frame touch-up — the corpus's Hewing Hatchet entry documents a forum account of a scrub used after a hewing hatchet to knock twist out of riven boards [SP20].

lineage

• ancestors / relatives:
  • The English/American Jack Plane (fore plane) — the scrub's cousin and, per converging sources, its tradition counterpart rather than its ancestor: in the English/American system rough-flattening was traditionally the fore plane's job; the scrub "doesn't fall neatly into the traditional English system" (Christopher Schwarz) [SP5][SP18].
  • The Continental German Schrupphobel ("rough plane") — a distinctly named wooden-bodied roughing plane, still manufactured today (ECE, Ulmia), narrower-ironed and heavily cambered, traditionally gripped by a front horn [SP9][SP14]. The Literary Workshop Blog describes it as "a plane about half the length of the English fore plane but used in the same manner" [SP4]. Run 378 built this out in full, including a German-language technical source on the anatomy and a scoping correction on the French terms riflard and varlope (the latter is a jointer plane, not a scrub-family tool).
  • France — a functional counterpart, not an absence. The original entry quoted one forum contributor that French woodworking "never had the equivalent of a Scrub Plane." That claim is withdrawn: it rested on one contributor and reached across a national tradition. The review reports that the French lexical sources define the riflard as a large plane with a convex blade used to dress and rough wood (CNRTL) and as a carpenter's roughing plane used before the varlope (Académie française) [manual, relayed]. French roughing practice used the riflard, a longer roughing plane with a convex cutter, rather than necessarily a short Stanley-style scrub. It is a functional counterpart with different form and sequence, not proof that France lacked rough-planing tools. (Run 582 built the riflard out in full, including an 18th-century Encyclopédie passage classifying riflard as one of two varlopes.) The forum figures for riflard (~57 cm) and varlope (~68 cm) and the Roubo/Storck remark are from that one contributor [SP2] and are held at forum confidence.
• descendants / modern competitors:
  • The powered jointer and thickness planer mechanize the same rough-to-flat job; in a fully powered shop the scrub is close to obsolete except on stock wider than the machine's capacity [SP16, Derek Cohen: "the scrub plane offers one the ability to quickly true up twisted boards, even if this is only in preparation for the powered tool, since a planer can only follow the line it is given"].
  • The electric hand planer — the corpus's own Power Hand Planer entry documents a first-person account (Steve Rozmiarek) of using an electric planer "as a scrub plane on... slabs... that have warped a little in drying" [SP22].
• contemporaries — related but genuinely different tools:
  • Stanley's No. 340 "furring plane" (1905–1917) — separately patented (Jefferson Allen, US 721,771, granted 1903) and routinely confused with the scrub; Allen's patent text pitches it for floor smoothing, and the surviving No. 340 is "a great simplification" of the patent, not a scrub [SP8].

Petroski lens — form follows failure, with the arithmetic stated. The scrub's anatomy answers one mechanical problem: how to take a very deep cut without the plane becoming unusable. For a circular-arc edge, the sagitta (centre projection of the curve over a chord of width w at radius R) is R − √(R² − (w/2)²). At R = 3 in this gives about 0.066 in for a 1¼ in chord, 0.095 in for 1½ in, and 0.172 in for 2 in (recomputed in this pass; the reviewer gives the same values). So a narrower cutter at the same radius makes a less extreme full-chord engagement, which is the sound qualitative point of the forum discussion [SP10]. Two cautions: the original entry's "about 1/16 in" and "roughly ⅛ in" came from a forum calculation, not a maker or engineering source, and are not accurate across the stated widths; and normal scrub use engages only a portion of the curved edge, so full-chord sagitta is not routine shaving thickness [SP10 for the forum discussion].

history

• Stanley's own timeline, as carried from the collector sources consulted:
  • No. 40 — 9½" long, 1¼" iron, ~2lb 2oz, made 1896–1962. Very thick single iron (no cap iron on this model), ground convex, very wide mouth [SP6]. Patrick Leach's collector type-study notes no patent is associated with the No. 40 [SP6].
  • No. 40½ — 10½" long, 1½" iron, ~2lb 8oz, made 1902–1948, "same as the #40, only a bit larger" [SP6]; scarcer and higher-priced today [SP23, collector-aggregate sourcing]. The reviewer reports a digitized 1902 Stanley catalog indexes the No. 40½ [manual, relayed].
  • Earliest dated product established in this pass: Stanley No. 40, listed from 1896 in the collector/catalog sources consulted. This is model history, not a worldwide invention record; no earlier-product search (museum or catalog survey) was done, so no claim is made that nothing earlier existed.
  • Stanley's 1923/1925 catalog language, quoted by two secondary sources: the scrub is for "planing down to a rough dimension any board that is too wide to conveniently rip with a hand saw" [SP4][SP5].
• ★ A sourced correction to this corpus's own Jack Plane entry. The Jack Plane entry cites "Hazard Knowles, US X4,859 (1827), 'Plane stocks of cast iron'" alongside its scrub discussion. Read on DATAMP in the original run: the patent covers cast-iron plane bodies generally, says nothing about camber or roughing, and the surviving example is a jointer plane [SP7]. The reviewer agrees and notes the Smithsonian's history of early American tools also presents it as a cast-iron plane-stock milestone [manual, relayed]. Flagged back to the Jack Plane entry.
• ★ A second near-miss patent. Stanley's No. 340 furring plane (1905–1917) carries Jefferson Allen's US 721,771 (March 3, 1903), pitched for smoothing floorboards in place. Stanley's 1911 catalog (No. 110, p. 38) describes the No. 340 as "for preparing lumber as it comes roughly sawed from the mill... will remove the fur, grit, dirt, etc.," but the article's author calls it "a great simplification" of Allen's patent [SP8]. The reviewer asks that the patent record itself be cited where possible rather than an article quoting a collector; that was not done here. Both patent leads are adjacent, neither squarely on target; the No. 40 appears to have entered the market with no patent of its own.
• A named, contested hypothesis on why Stanley introduced the No. 40 in 1896 — reported, not adopted. A tool-history blogger's labeled hypothesis ties the iron scrub's introduction to peak European immigration (1892–1900) and the wooden Continental Schrupphobel [SP4]. A commenter found scrub-plane marks "beneath the base frames of built-in cabinets" in a 1914 Los Angeles house [SP4]. That anecdote supports period use, not the immigration-marketing theory.
• Older English roughing geometry (not Continental naming). Joseph Moxon's Mechanick Exercises (1677–1684) is reported to describe the English fore plane's iron as "ground to a convex arch in the middle rather than a straight edge." That is evidence of seventeenth-century English fore-plane geometry, showing that aggressive convex roughing irons predate the English term "scrub plane." It does not establish Continental naming or direct ancestry. The text was retrieved only through a search snippet, so this is graded as partial evidence, not a primary-source finding [SP11].

✦ human side

• Christopher Schwarz tested removing ¼" from an 8'-long 2×12 edge. His words: "The scrub did the job remarkably well, especially when I didn't try to use the tool like a jointer plane. Instead of taking a long continuous pass on the edge, I started at the left end of the board and took short, choppy strokes... It was indeed faster than any ripsaw I've used and was on par with the stock removal rate of a drawknife (but with more control)." He notes his beat-up jack plane is more reliable than his scrub for truing a face, because of the longer sole [SP5].
• Derek Cohen, who owns and has compared a Stanley No. 40, a Veritas, and a shop-built wooden scrub: "Oh what fun this plane was!... a revelation to experience how quickly and effortlessly... material could be hogged away." On conversions: "Could one substitute a re-treaded smoother as a scrub? Well, with a suitably cambered blade it will work, but it will not hold a candle to a dedicated scrub plane" [SP16].
• Paul Sellers has taught the jack-to-scrub conversion on video; a Sawmill Creek poster summarizes his method (as relayed, not verified here): "He used a 7-inch radius for the camber, knocked the corners of the chip breaker off, and slightly enlarged the mouth of the plane with a file" [SP3][SP10]. This is one teacher's method on one plane, not a general recipe.
• A named practitioner disagreement. The Sawmill Creek thread "The essential scrub plane?" opens with a claim attributed to Anthony Guidice (Fine Woodworking, June 2000) that the scrub is the only tool that can truly flatten a board. Respondents dispute it, e.g. Assaf Oppenheimer ("I only break out my scrub to roughly dimension... I use my no.5 to flatten the board"), Rob Luter, and Warren Mickley [SP2]. The claim is wrong because of the word only, not because a scrub cannot contribute to flattening; see lineage-misuse.
• Two named first-person accounts. Tom M King describes using a decades-old scrub plane to clean up salvaged 19th-century heart-pine train-station beams [SP2]. Jim Koepke ("jtk") describes converting several bargain-bin bench planes into scrubs and calls it "an epiphany" [SP2][SP10]. These are accounts of work on reclaimed timber, not endorsements of skipping inspection (see matching).
• The DIY conversion tradition. Joe Foster converted a rusty 1930s "Defiance" jack plane, bought for $10, into a scrub; his rule: "The plane should not be valuable... if you have a Stanley Bedrock, you shouldn't modify it! Instead try a $5-$20 plane" [SP17].
• An honest gap: Reddit (r/handtools, r/woodworking) was inaccessible to the original run [see open gaps].

✦ proof of existence

• earliest dated product established in this pass: Stanley No. 40, listed from 1896 in the collector sources consulted (Leach); no patent is attached to it [SP6]. Bounded to this search scope.
• two patents researched, both adjacent rather than on-target: Hazard Knowles, US X4,859 (1827), "Plane stocks of cast iron" [SP7]; Jefferson Allen, US 721,771 (1903), underlying the No. 340 furring plane [SP8].
• trade-catalog evidence: Stanley's 1911 Catalogue No. 110 (p. 38) for the No. 340 via a collector source citing Roger K. Smith; Stanley's 1923/1925 language for the No. 40 via two secondary sources, not checked against a scanned original [SP4][SP5][SP8].
• honest gap — museum records: no Mercer Museum, Smithsonian or V&A record naming a scrub plane was located in the original run's limited searching.

references

The reviewer's corrections (12)

• BLOCKER — 1. Replace the empty safety class — Exact claim: “Genuinely and fully empty” and “No injury, accident, or near-miss account attributable to the scrub plane specifically was found … the DANGEROUS class is genuinely and fully empty.”
• BLOCKER — 2. Correct the claim that a scrub plane cannot flatten a board — Exact claim: The scrub is “useless the moment flatness is actually required,” “cannot replace … [a plane] for actually truing,” and the named debate is “mechanically settled” because the short sole follows undulations.
• BLOCKER — 3. Remove the universal single-iron/no-chipbreaker claim — Exact claim: “a single, thick blade (no cap iron/chipbreaker on any production model, past or present)” and “confirmed across every maker, historical and current.”
• SHOULD-FIX — 4. Correct the universal no-adjuster claim and stale Infinity listing — Exact claim: “no fine mechanical adjuster on any maker's current product,” followed later by an Infinity scrub “with a Norris-style brass adjuster.”
• SHOULD-FIX — 5. Reframe the tool sequence as one workflow, not the classic universal lineage — Exact claim: “one step before the jack in the classic English/American flatten-a-board sequence: scrub → jack → try/jointer → smoother.”
• SHOULD-FIX — 6. Fix the French-tradition claim — Exact claim: “French woodworking never had the equivalent of a Scrub Plane,” with the added assertion that the riflard was not cambered like a scrub.
• SHOULD-FIX — 7. Correct the Moxon/Continental terminology inference — Exact claim: “The Continental terminology predates the English name by centuries, on a primary-source basis,” supported by Moxon's English description of a convex fore-plane iron.
• SHOULD-FIX — 8. Bound the “earliest” and “founding” history claims — Exact claim: “earliest confirmed dated commercial product: Stanley No. 40, introduced 1896” and “the founding American iron scrub planes.”
• SHOULD-FIX — 9. Correct the camber-depth calculation and its evidentiary weight — Exact claim: A 1¼–1½-inch cutter at a 3-inch radius gives “about a 1/16-inch” center cut, while a 2-inch cutter gives “roughly ⅛ inch,” presented as quantified engineering.
• SHOULD-FIX — 10. Repair the finish-use contradiction — Exact claim: “not-for … any finish surface” and “strictly a pre-finishing, first-stage tool,” while the same entry says it can leave an “interesting textured feature” as a legitimate final step.
• BLOCKER — 11. Make the reclaimed-stock match safe and material-aware — Exact claim: The tool suits “reclaimed lumber of unpredictable dimension,” “salvaged beams,” and “firewood-grade stock,” with no corresponding contamination or embedded-metal control.
• SHOULD-FIX — 12. Bound the DIY conversion instructions — Exact claim: Convert a cheap jack/smoother by “regrinding … to a 2–8 inch radius camber and widening the mouth by filing or moving the frog back,” presented as a common, low-barrier entry point.