A 3/4″ single output plug-in output shaft for flexible-mount right-angle speed reducers. It converts the reducer's hollow output bore to a male keyed stub. 5.43″ overall with a 3/16″ square keyseat and a 1/4-20 end retention tap. Crosses McMaster 6771K51. Load it as a configurable starting point. Material, tolerances, and features stay editable, and we confirm full geometry against your reducer or old shaft before we cut.
3/4″ Single Output Shaft profile (configurator preview)
Material, tolerances, and features (keyseat size, end retention tap, extra flats or grooves) stay editable in the configurator. The shaft diameter, overall length, keyed-output length, and tap thread are taken from the published catalog data; the keyway dimensions and exact tap depth are standard-derived and confirmed against your reducer or your old shaft before we cut, the drawing's title block stamps the source SKU so any deviation is visible to your buyer and to us.
Machined from 1045 by default. See the 1045 material guide, or change the grade in the configurator.
Frequently Asked Questions
It converts a flexible-mount right-angle reducer's female (hollow) output bore into a male, keyed output stub so you can drive a sprocket, pulley, or coupling. The reducer turns the shaft through two central keyseats in its bore; the shaft then delivers torque at a keyed output end, one (single output) or both (dual output). So a single-output shaft has 3 keyseats (2 central drive + 1 output) and a dual-output has 4 (2 drive + 2 output), plus an axial retention tap at each output end and two retaining-ring grooves for axial retention (the catalog single-output parts are machined with an integral shoulder and a single groove instead — see the sourcing question below). Each loads into the configurator with all of that pre-placed. We supply the machined shaft only — keys, key stock, and retaining rings are not included.
Match the shaft diameter to your reducer's output bore and choose single or dual output. The diameter then fixes the keyway size (ANSI B17.1 square key) and the retention-tap thread. If you're replacing a catalog part, the cards cross-reference the McMaster 6771K SKUs. Pick the card whose diameter, length, and output count match.
The single- and dual-output cards fit the standardized NEMA-input aluminum worm-reducer pattern (often called the NMRV or aluminum-worm pattern) that the McMaster 6771K shafts replace. The same output bores (3/4, 1, 1-1/8, 1-1/4, 1-3/8 inch) appear across IronHorse WGA, WorldWide Electric CALM, and Motovario NMRV gearboxes, so a card matched by bore diameter, length, and output count fits that family. Confirm the bore and length against your reducer before ordering; we verify the geometry against your unit or old shaft before cutting. (The Dodge Tigear-2 cards are a separate, Dodge-specific pattern.)
Yes. The Hollow-to-Solid Conversion cards turn an installed cast-iron worm reducer with a hollow output bore into a solid keyed output — no OEM sells this for the cast-iron worm line. The shaft drops into the reducer's existing hollow bore, is keyed to the hub's furnished key, held by the hub set screws and a retaining ring, and presents a keyed output stub. Boston 700 (718/721/724/726/732), IronHorse WG (175-325), and WorldWide HdR share the same size envelope, so one card covers all three by center-distance size. Bore and output dimensions come from the OEM catalogs and the body length from IronHorse's own CAD; Boston units are bored to size, so confirm your bore code and we verify against your reducer before cutting.
All keyways are a standard ANSI B17.1 square keyseat sized to the shaft diameter (3/16″ up to 7/8″, 1/4″ through 1-1/4″, 5/16″ at 1-3/8″). There are two central keyways where the reducer drives the shaft, plus one at each keyed output end (single = 3 keyseats, dual = 4). Each output end also carries a UNC retention tap (1/4-20, 3/8-16, or 1/2-13 by size) for a washer-and-bolt that holds the driven component on. Every dimension stays editable in the configurator.
The cards default to 1045 medium-carbon steel, a good general-duty reducer-shaft material. For higher strength switch to 1144 stress-proof or an alloy in the configurator. Material certs (MTRs) are available on request.
The shaft diameter, overall length, keyed-output length, and retention-tap thread are taken from the published catalog data, and the keyseat structure — the two central reducer-drive keyseats plus the output keyseat(s) — from the McMaster drawings (6771K439 single, 6771K441 dual). Retention is where we differ, and it is worth knowing before you order: we cut two retaining-ring grooves on every size, while the catalog singles are machined with an integral shoulder and a single groove. We measured the 3D models to be sure — the dual (6771K441) has two grooves and no shoulder, but both singles we checked (6771K51, 6771K439) have one groove and an integral shoulder. That difference is one of the things we check against your reducer before cutting. The exact keyway lengths, ring-groove dimensions, the small drive-zone turn-down, and the feature positions for sizes other than 1-3/8″ are standard-derived/scaled and confirmed against your reducer or your old shaft before we cut. The drawing title block stamps the source SKU so any deviation is visible to you and to us.
Yes, all ten case sizes. The Tigear-2 architecture differs from the generic plug-in shafts: a stepped shaft (bore-riding body with a smaller keyed output stub), a single central bore keyseat driven by the reducer hub's furnished key, two snap-ring grooves for axial retention, and no end tap (the hub's set screws bear on the shaft). Stub diameter, projection, overall length, and both key sizes come from the Dodge catalog, and the body geometry is taken from Dodge's own CAD models. Like Dodge's kits, these fit standard-max-bore Tigear-2 reducers only.
These cover the common 3/4″ through 1-3/8″ flexible-mount right-angle reducer shafts in single and dual output, plus the Dodge Tigear-2 kit sizes 13 through 47. For another diameter, length, brand, or a different keyway, load the closest card and edit it, or send us a print or the old shaft and we'll match it.
Dodge, Tigear-2, McMaster-Carr, IronHorse, WorldWide Electric, Boston Gear, Motovario, NMRV, and all other reducer model, kit, and brand names shown are trademarks or trade names of their respective owners. Great Lakes Shafts is an independent manufacturer and is not affiliated with, sponsored by, or endorsed by any of them. These are aftermarket replacement shafts machined to fit the referenced reducers; the names are used only to identify the equipment our parts fit.