Rotary Microtome

Quick Answer: The Rotary Microtome is a histology instrument that cuts thin serial sections from paraffin-embedded tissue blocks, using a handwheel to move the block up and down past a fixed knife while a feed advances it after each cut. A rotary microtome is the usual workhorse for paraffin section cutting.

Why the Rotary Design Is Widely Used

Each turn of the handwheel drives the specimen block down past the knife in a straight vertical path and then back up, while the feed mechanism moves the block toward the knife by the set section thickness. Because the path is straight and the block is held rigidly, sections come off flat and even, and one sticks to the next to form a long ribbon. That ribbon is floated on a warm water bath and picked up onto glass slides in sequence.

Serial sections in order are the reason to choose this design: a student can follow a structure such as a gland or a developing embryo through consecutive slides. The listing does not state the thickness range, the specimen clamp type or the knife holder, all of which are worth comparing between models. LabEquip also lists an Erma type rotary model; ask which suits your blocks if you are deciding between the two.

Paraffin blocks for sectioning come from a processing and embedding step, which the Automatic Tissue Processor with Microprocessor automates.

Specifications

Applications

• Routine paraffin sectioning in histology and histopathology laboratories
• Serial sections of embryos and organs for developmental biology teaching
• Cutting sections for special stains and immunohistochemistry
• Making student-prepared slides in practical histology courses

Care & Handling

• Engage the handwheel lock of the rotary microtome, where fitted, before touching the knife or the block.
• Use a soft brush, never fingers, to lift ribbons and clear wax from the knife.
• Clean wax debris from the feed and clamp after each session and apply light oil only where the manual specifies.
• Fit the knife guard whenever the instrument is not cutting, and put used disposable blades straight into a sharps container.

Why Choose LabEquip

Pathology laboratories, medical and veterinary colleges and university zoology departments buy handwheel microtomes for regular paraffin work. This one is listed in the LabEquip Microscope & Optics range; mention whether you use steel knives or disposable blades on the contact page.

Frequently Asked Questions

What is a rotary microtome used for?

It cuts thin, even sections from paraffin wax blocks of tissue for mounting on slides and staining. The rotary action produces ribbons of consecutive sections, useful when a structure has to be followed through the tissue.

How do I get a good ribbon?

Trim the block so its top and bottom edges are parallel and square to the knife, use a sharp blade, and turn the handwheel at a steady speed. A slightly chilled block and a room that is not too warm help sections stick together.

Why do sections have lines running through them?

Vertical scratches are nearly always caused by a nick in the knife edge or a hard particle in the tissue. Move the blade sideways to a fresh area or replace it.

Can the same instrument cut frozen tissue?

A standard handwheel microtome at room temperature is for paraffin blocks. Frozen sections are cut on a cryostat, which houses a microtome inside a refrigerated cabinet, or on a freezing microtome.

What is the difference between a steel knife and a disposable blade?

Steel knives can be resharpened and give very good sections, but need honing and careful handling. Disposable blades fit a special holder and are replaced when dull, which saves sharpening time in busy laboratories.

How should the microtome be cleaned?

Brush away wax and section debris after each use, wipe surfaces with a cloth lightly moistened with a wax solvent if needed, and keep solvent away from lubricated parts. Remove and clean the blade holder periodically.

Last Updated: September 2026