OMEF Big Inch BI300 vs TMK TMK 300 Tree shear

Short answer

Which one fits which job?

These are close enough that the carrier match, witnessed hardwood cycle and support path should override brand preference. Quote both with coupler, hoses, installation and realistic wear parts included.

Published figures

Specification comparison

Different manufacturers publish different fields. A dash means the equivalent figure is not included in this guide—not zero and not necessarily unavailable.

Specification	OMEF Big Inch BI300	TMK TMK 300
Carrier class	8-14 t	~6-20 t excavators
Weight	420 kg	—
Maximum published cut	300 mm	—
Australian distributor	Randalls	—
Bare attachment weight	—	~310 kg
Hardwood capacity	—	up to ~250 mm
Softwood capacity	—	up to ~300 mm
Hydraulic flow	—	~50-150 L/min depending on cylinder arrangement

Decision gates

The figures that should decide this comparison

Published hardwood capacity
Bare and installed attachment mass
Flow requirement for the quoted configuration
Australian parts and field-service lead time

Commercial fit

Where each model earns its place

OMEF Big Inch BI300

420 kg shear for 8-14 t excavators, 300 mm published maximum cut — the regrowth and fence-line workhorse.

Regrowth control, fence lines, shelterbelts and fire-break work in the 100-200 mm class
Contractors with an existing 8-14 t excavator that needs to earn across several industries
Work where stems per minute matters more than occasional large capacity

TMK TMK 300

310 kg shear for 6-20 t excavators — 250 mm hardwood, 300 mm softwood, and the difference matters.

Mid-size vegetation and clearing work on a common 6-20 t excavator
Contractors who need a light attachment that barely touches the lift chart
Mixed work where the same carrier changes attachments through the week

Full due diligence

Open both model buyer guides

OMEF

Big Inch BI300

Specifications, commercial fit, ownership considerations and checks before signing.

TMK

TMK 300

Specifications, commercial fit, ownership considerations and checks before signing.

Do not compare these models outside the production system

The winning specification can still produce the higher whole-life cost if another machine, the landing or haulage constrains its output. Recheck the tree shears buying guide and calculate cost per saleable unit at your contracted hours.