[ You are here >> Products >> testing - Knives, blades >> Blade Edge profile ]

Blade Edge Profile Microscope

Designed and Manufactured by CATRA

Blade edge sharpness is mainly controlled by the edge angle and edge thickness, and in the case of wavy edge blades the pitch and shape now in a single instrument these parameters can be quickly and accurately determined, including the recording of a visual image of the cutting edge section profile.

Knowledge of the cutting edge geometry of a blade is essential information in determining the potential sharpness of any sharp edge cutting device. The unit is suitable for quality control, research/ development and product comparisons uses.

The Technique

CATRA has been looking at blade cutting edge profiles for over 60 years by impressing a knife edge into a soft media and projecting the image on to a screen for manual copying and calculation. Now we have miniaturised the process and semi automated it by recording the impressed image by microscope camera and computer. The software collects the image of the edge and with operator guidance measures the required edge angle and thicknesses.

The Process

A simple holder carries a small quantity of soft test media, into which is impressed the knife edge to be examined. The holder is then slotted into the microscope which can be adjusted for focus and light intensity to give the optimum image.

The cutting edge portion of the blade sectional profile is then shown on your PC or laptop utilising the software supplied. The user then identifies the facet angles to be measured, the software then automatically measures the bevel angles and the blade thickness at the standardised reference point of 1 mm (0.040") back from the tip of the edge. Blades which have a gothic arch edge or have multiple facets angles can also be accommodated, with the software measuring the angles of each facet, as shown below. Measurement of facet/ bevel lengths or blade thicknesses at other points of the blade can also be made using a simple click and drag facility.


As well as providing dimensional information the user will become experienced in understanding the blade edge profile, such that the knowledge can be used to control quality, develop and design sharpening systems and their operation. Also an indication of edge tip radii can be made on blades that are worn.

Scallop and serration profiles

The device can also be used to evaluate the pitch, shape and angles of a wide variety of serrations and scallops on blades edges, by simply placing a blade/ knife edge into the machine, without the use of the soft media. This gives a clear and accurate picture of the edge, such that the built in measuring facility can be used to determine the actual parameters of edge forms. It will also clearly indicate the cleanliness of the edge in terms of burrs and metal particles.


Other Applications

The unit can be used also to examine needles, hypodermic needles, fishing hooks, etc



The Device

Made in the United Kingdom by CATRA, the microscope, camera and lighting unit are housed in a rigid aluminium body, which provides a robust alignment of all of the components. Complete with power cable, USB cable, test media (which is reusable) and software, the system can be set up and in use in matter of minutes.

The inbuilt database not only stores blade information, angle, thickness data but also the photo profile.


Computer requirements ( computer not supplied)

This device is one of many cutting test instruments made by CATRA, all of which can be seen in our cut testing laboratory in the UK.

Please contact us by phone or e-mail for our latest brochure and prices.

Top of the page

CATRA, Henry Street, Sheffield S3 7EQ, Great Britain Fax: +44 (0)114 272 2151 Tel: +44 (0)114 276 9736