Types of cutting action:
Chopping or slicing?
Possibly the most difficult selection concerning knife blades is whether the cutting action should be chopping or slicing. Chopping directly through with a straight edged blade causes the least amount of hold-up time and, therefore, the least interruption to the extrudate as it is continuously pushed forward by the caterpillar infeeder belt.
Slicing through the product with a curved blade tends to give a better-cut quality but can considerably increase extrudate interruption time.
Using a static cutter, such as the Servo-Torq®, with a continuously moving product demands a compromise between slicing angle and engagement time.
The type of blade you should use will obviously depend upon your application. However, in our experience, approximately 90% of products can be cut adequately with a straight edged ‘chopping' blade.
The remaining 10% are best served with a curved ‘slicing’ blade. Typical products would be thin-wall tubes or profiles, or profiles with an intricate shape where a chopping action might cause material distortion or collapse.
We can offer you a selection of straight or curved blades, or produce a custom blade design especially for your product.
Please download an article on improving your cutting process here: Cutting Hints (PDF file).
Additional advice is always available from GILLARD. Experienced staff would be pleased to share their knowledge to help you achieve the best possible results from your Servo-Torq® cutter system. Please email our Technical Team for more advice: firstname.lastname@example.org.