Disston’s chainsaw range was much smaller than the likes of McCulloch’s, but its names are unusually easy to misread. U.S. Army equipment designations, Disston sales names, and Kiekhaefer Mercury engine codes all appear in surviving literature, sometimes for the same basic machine.
This list covers every documented production chainsaw sold with Disston branding or identified as a Disston model in period government literature. It includes gas and pneumatic saws, keeps every credible exact designation visible, and separates materially different versions.
A Brief History
Henry Disston began making saws in Philadelphia in 1840, according to the company’s official history. More than a century later, Henry Disston & Sons added powered chain saws to a business already famous for hand saws, crosscut saws, steel, files, and cutting tools.
Disston’s gasoline saws were a partnership in practical terms. Kiekhaefer Corporation, better known through its Mercury name, supplied the air-cooled two-cycle engines and related power-unit components. Disston supplied the guide rails, chains, tailstocks, and saw expertise, then sold complete machines under the Disston name.
The U.S. Army bought early gasoline and pneumatic versions during World War II. Postwar buyers could choose large two-man Mercury twins, the smaller DO one-man saws, the intermediate DA-211, or compressed-air P-Series machines.
Henry Disston & Sons became a division of H. K. Porter in 1955. A small group of lightweight West Bend-powered development saws built around 1954-1955 never reached production, so they are not included below.
Gasoline Chainsaws: World War II Models
G-10 (Mercury KB6-A)
- Production: 1942-1945
- Displacement: 245 cc (15.0 cu in)
- Power: 4.5 kW (6 hp)
- Weight: 44.0 kg (97 lb), with 61 cm (24 in) bar and chain
- Guide-bar range: 61-213 cm (24-84 in)
The Army’s October 1942 TM 5-4002 identifies the complete saw as Disston Model G-10 and its Mercury engine as KB6-A. KB6-A is therefore an engine designation, not a second Disston model.
G-26 and G-36 (Mercury KB6-AX)
- Production: Introduced by May 1943; documented in a revised October 1947 Army manual
- Displacement: 245 cc (15.0 cu in)
- Power: 4.5 kW (6 hp)
- Weight: G-26, 42.6 kg (94 lb); G-36, 44.9 kg (99 lb)
- Guide bar: G-26, 61 cm (24 in); G-36, 91 cm (36 in)
These are the 24- and 36-inch configurations of the same two-man gasoline saw. The 1947 Department of the Army manual covers both together and specifies a two-cylinder, alternate-firing engine governed to 4,000 rpm. Earlier Army literature connects the family with the Mercury KB6-AX engine.
G-AY and KB6-AY
- Production: G-AY, 1943-1945; KB6-AY introduced 1945
- Displacement: 245 cc (15.0 cu in)
- Power: 5.2 kW (7 hp)
- Weight: 44.0 kg (97 lb), with 61 cm (24 in) bar, chain, and tailstock
- Guide-bar range: 61-213 cm (24-84 in)
Collector service records identify the government-tagged G-AY as the military version of the KB6-AY family. The latter name is the Mercury power-unit designation commonly found in manuals and on surviving saws. This 7 hp family should not be confused with the later 11 hp KB7-AY.
Gasoline Chainsaws: Postwar Mercury and Disston Models
G-311, G-411, G-511, G-611 and G-711
- Production: Postwar; documented in Disston factory Manual No. G-11
- Configuration: Two-man gasoline saw with Mercury engine
A surviving factory manual cover explicitly lists all five model numbers. G-11 is the manual number, not another saw model. The shared 80-page operation, maintenance, and parts manual establishes that the five codes belong to one family, but the available cover and sample pages do not justify assigning an individual bar length or engine specification to each code.
KB7-AY, 11 hp version
- Production: 1947-1950
- Power: 8.2 kW (11 hp)
- Weight: 44.0 kg (97 lb), with 61 cm (24 in) bar, chain, and tailstock
KB7-AY is a Mercury engine and power-unit designation that became the everyday collector name for the complete Mercury-Disston saw. It overlaps the era and construction of the factory G-311 through G-711 family, but the surviving Disston manual cover does not provide a one-to-one cross-reference, so the codes are not presented as exact aliases.
KB7-AY, 12 hp version
- Production: 1948-1950
- Power: 8.9 kW (12 hp)
- Weight: 44.0 kg (97 lb), with 61 cm (24 in) bar, chain, and tailstock
This higher-output KB7-AY is listed separately because its published 12 hp rating is a material change from the 11 hp version, even though the designation and basic two-man chassis remained the same.
DH-120 (Mercury KB7-B)
- Production: KB7-B version, 1948-1950; DH-120 cataloged in 1949 and still documented in 1952 literature
- Displacement: 245 cc (15.0 cu in)
- Power: 8.9 kW (12 hp) at 4,000 rpm
- Weight: 44.5 kg (98 lb), net with 61 cm (24 in) bar, chain, and tailstock
- Guide-bar range: 61-213 cm (24-84 in)
Disston marketed the DH-120 as its Extra-Duty two-man saw. The twin-cylinder engine, multiple-disc hand clutch, bevel-gear drive, automatic pressure chain oiler, and available 2- to 7-foot rails are specified in the 1949 Disston Catalog No. 100-R9. Mercury KB7-B is the related power-unit designation found in service and collector literature.
DO-100
- Production: 1948-1949
- Displacement: 90 cc (5.5 cu in)
- Power: 2.6 kW (3.5 hp) at 4,000 rpm
- Guide bar: 38 cm (15 in) bow, or 46-61 cm (18-24 in) straight bar
The DO-100 was Disston’s early one-man Mercury saw. It used gear reduction, a rear-handle manual clutch, automatic chain oiling, and a 1.66 L (3.5 US pt) fuel tank. The optional bow was a cutting attachment, not a separate model.
DO-101
- Production: 1950-1951; dealer advertising continued into 1955
- Displacement: 90 cc (5.5 cu in)
- Power: 2.6 kW (3.5 hp)
- Guide-bar range: 46-76 cm (18-30 in)
The DO-101 continued the single-cylinder, gear-drive layout with a manual clutch controlled from the rear handle.
A 76 cm (30 in) rail could take a helper handle for two-person work, while the standard saw remained a one-man model. A January 1955 dealer advertisement proves that new old stock remained on sale well after the commonly cited 1951 production endpoint.
DA-211
- Production: 1951-1953
- Displacement: 180 cc (11.0 cu in)
- Power: 6.7 kW (9 hp)
- Weight: 24.9 kg (55 lb), powerhead only
- Guide-bar range: 61-213 cm (24-84 in)
The DA-211 was Disston’s lighter Intermediate saw, with a horizontal opposed twin, centrifugal clutch, magnesium construction, and one- or two-person capability.
A 1952 period advertisement confirms the 9 hp rating. Kiekhaefer also sold the closely related KA-211 under its own name, but that non-Disston-branded version is not a separate entry here.
Pneumatic Disston Chainsaws
Disston’s compressed-air saws were intended for logging, industrial, underground, and underwater work where a gasoline engine could be unsuitable. They used vane motors, bevel-gear drive, and a tailstock at the far end of the guide rail.
Model 67
- Production: Introduced 1942
- Motor power: 2.6 kW (3.5 hp), six-vane air motor
- Air requirement: 620 kPa (90 psi) at 2.55 m³/min (90 cfm)
- Guide-bar range: 41-61 cm (16-24 in)
The specialist Model 67 profile records one- or two-person operation and a gravity-feed tailstock oiler. No factory document has been found that explicitly equates Model 67 with the later military P-7, so they remain separate entries.
P-7
- Production: Documented in 1943 U.S. Army manuals
- Guide bar: 61 cm (24 in)
War Department TM 5-4012 names this machine “Saw, Pneumatic, Chain, Portable, 24-Inch, Model P-7, Disston.” The exact military designation is important because P-7 is absent from Disston’s later commercial P-Series catalog page.
P-27
- Production: Introduced 1945; cataloged in 1949
- Motor power: 2.6 kW (3.5 hp)
- Air requirement: 620 kPa (90 psi) at 2.55 m³/min (90 cfm)
- Weight: 20.6 kg (45.5 lb), net
- Guide bar: 61 cm (24 in)
P-275
- Production: Cataloged in 1949
- Motor power: 3.7 kW (5 hp)
- Air requirement: 620 kPa (90 psi) at 4.25 m³/min (150 cfm)
- Weight: 22.0 kg (48.5 lb), net
- Guide bar: 61 cm (24 in)
P-375
- Production: Cataloged in 1949
- Motor power: 3.7 kW (5 hp)
- Air requirement: 620 kPa (90 psi) at 4.25 m³/min (150 cfm)
- Weight: 24.3 kg (53.5 lb), net
- Guide bar: 91 cm (36 in)
The P-27, P-275, and P-375 appear together in Disston’s 1949 catalog. The P-275 and P-375 are listed separately because their 5 hp motor, air consumption, weight, and bar equipment differ materially from the 3.5 hp P-27. Their guide assembly could rotate for felling, bucking, or inverted cutting, and the catalog specifically promoted underwater operation.
Let us know if we’ve missed any!
