Cutoff Knives for Higher Conversion Efficiency, Lower Machine Stress

Cutoff Knives for Higher Conversion Efficiency, Lower Machine Stress

The more innovations made in new films and foils, the more likely converters and form fill seal users will find their old knives just “won’t cut it” with the new substances. Poor and incomplete cuts, excessive blade wear, and rough edges on cut material are a fairly easy problem to diagnose: the current cutoff knife just isn’t the optimal cutting edge for the challenges the new material presents.

So what about all-out catastrophe like blade bending? Or worse, blade holder bending? In these cases, manufacturers may begin to worry an epic failure is at hand. That – never mind the blade – maybe the machine itself doesn’t have the power to make the cut. Worries about the cost of machine upgrades and the associated downtime can quickly begin to mount.

But, they shouldn’t. At least not quite yet, anyway.

V-style teeth are most common in converting and form fill seal applications.

Even seemingly disastrous situations like this might be remedied without a complete rework of the production line. With a little bit of science and engineering expertise, a reconfigured cutoff blade might be just the right solution – saving your production line at the fraction of the cost of starting from scratch with new equipment.

V-Style profiles on cutoff knives offer countless options for edge geometry, serrations, and blade materials for guillotine-type cuts on films, papers, and foils alike.

In particular, both Vari-Depth and Hi-Low tooth profiles are designed to help make a cleaner cut that reduces the load on the cutting machine itself:

Vari-Depth Cutoff Knives

Vari-depth (or vari-tooth) profiles help reduce machine stress when cutting tougher materials.

While Standard V blades feature the tooth pattern at the same height along the width of the blade, Vari-Depth profiles stagger the teeth vertically to regulate actual contact between the cutting edge and the material itself. Instead of having to force every tooth to slice a material at one time, only a fraction are initiating the cut at any given moment.

Dissipating the cutting force in this manner helps limit stress on the material, the blade, and the machine itself – without the need to add more power to your machines or invest in new equipment altogether.

Where Standard V configurations may cause blade bending or a less-than thorough cut, vari-depth configurations might work like a dream.

Hi-Low Cutoff Knives

Given this machine stroke, the Hi-Low Blade (A) is able to fully cut through the material where the staggered Vari-Pitch (B) blade cannot.

Hi-Low Profiles help reduce stress for shorter-stroke cutoff operations.
Then again, sometimes the more “exotic” tooth geometries simply aren’t suited for the staggered vari-depth profile. In some cases, the vari-depth pattern doesn’t allow the specific geometry needed. In others, the machine cutoff stroke may not be long enough to allow the whole blade to pass through the material (figure 1).

In either case, hi-low profile machine knives might be just the right solution.

The alternating tooth height (“Hi” and “Low”) still offers a level of dissipated force and can likewise help ease some cutting operations. At the same time, the base of the teeth are parallel like the Standard-V configuration, ensuring the full cutting surface will pass through the material in the given stroke.

No matter what configuration you end up with, the point of it all is that there are a million and one ways to manufacture a blade that is efficient, cost-effective, and puts the least amount of stress on your machines as possible – on any kind of material.

Is Your Cutoff Operation Failing? We Can Help.

Our manufacturing team has a century’s experience manufacturing custom machine knife solutions for converting, form fill seal, and processing applications – we even offer free cutoff knife test cutting services to help you find the optimum cutting edge without breaking the bank.

Submit your request for quote today, or give us a call to speak to any of our trained sales engineers.

Of course, I say “simple” because it’s what we do every day. Blade profiles themselves come in a million configurations – it’s not necessarily that “simple” … but I digress…

What I should have said is this: