Center hole
Round mower blade center hole: measure the inner diameter
Round center holes are measured by inner diameter. Oregon's 96-347 has a 5/8 in hole and its 91-635 a 3/4 in hole, both 21-inch-class Gator G3 blades.
Also listed as round hole, round center hole
Short answer
A round center hole is identified by its inner diameter. Oregon records round holes by size: its 21-inch Gator G3 96-347 has a 5/8 in hole and its 21-1/8 in G3 91-635 a 3/4 in hole. Two blades of almost the same length can need different holes, so measure yours and match the part number.
Key facts
- How to recognize it
- A plain circular hole in the middle of the blade, with no points, flats or slots.[1]
- How to measure or name it
- Measure the inner diameter of the hole.[2][1]USA Mower Blades' method; Oregon's catalog records round holes by size.
- What it mounts to
- Not confirmedNo maker in the sources read states what a round hole mounts to.
- How catalogs name it
- Oregon's Blades by Length catalog records round center holes by their size.[1]
- Blades made with it
- Oregon 96-347 (21 in Gator G3): 5/8 in center hole, 2.50 in wide, 0.203 in thick, zero offset. Oregon 91-635 (21-1/8 in Gator G3): 3/4 in center hole, 1/4 in offset, 0.187 in thick.[3][4]
- Mowers and decks that use it
- Oregon lists 91-635 as a replacement for Cub Cadet, cross-referencing 742-04101 and 759-3830 (Cub Cadet/MTD). Oregon names SCAG as the major brand 96-347 replaces.[4][3]Brand names, not model lists; confirm your model.
- Common mix-ups
- Two 21-inch-class blades with different hole sizes: 96-347 at 5/8 in and 91-635 at 3/4 in. A hole name alone never establishes fit; Oregon always records the hole with a part-specific record.[3][4][1]
- Not confirmed
- Not confirmedWhich mower models use each hole size, and what the hole mounts to on each mower.
Watch out for
- Never drill, grind or file a center hole to fit, and never fit a blade whose hole does not match your spindle or adapter.
- 5/8 in and 3/4 in round holes look alike at a glance. Measure the inner diameter.
This page describes a hole shape. It is not a fit list: use the blade's part number and your mower's model.
Questions
How do I measure a round center hole?
Measure its inner diameter. Oregon records round holes by size, such as 5/8 in on 96-347 and 3/4 in on 91-635.[2][3][4]
Can I enlarge a 5/8 in hole to fit a 3/4 in spindle?
No. Never drill, grind or file a blade; order the part number your mower takes.