K873

A direct replacement for the Zund Z73 (5005572), Kongsberg BLD-TZ129 (42435636), and Summa 500-9825, with no holder modification needed. Triple edge tungsten carbide V-cut blade for V-grooving, bevel cutting, and 0° through cutting on Zund, Kongsberg, Esko, and Summa flatbed cutting systems.

Sold individually.

Direct OEM replacement

The K873 replaces the Zund Z73 (5005572), Kongsberg BLD-TZ129 (42435636), and Summa 500-9825. Same form, same fit, same mounting geometry. It drops into your existing V-cut holder with no changes.

What is V-cutting?

V-cutting uses angled cuts to remove a wedge-shaped strip from the material. That gives you clean folds, beveled edges, and mitered joints in thick board, acoustic felt, and display materials. Set at 0°, the blade also makes straight through cuts. This is not a kiss-cut blade.

Three cutting edges

The K873 is sharpened on the bottom edge and both angled sides. As the blade enters the material, the angled edges slice in instead of pushing through. That lowers entry force, cuts down on blade deflection, and gives you a cleaner, more accurate start point on the cut path. It also puts less stress on the blade and the material, which means smoother cuts and longer blade life.

The difference shows most in dense PET felt, Zintra®, foam board, and heavy corrugated, the materials that push a standard blade off line when it enters.

Tungsten carbide construction

Tungsten carbide holds an edge longer than high-speed steel and resists wear from abrasive materials like PET felt and fiber board. That means fewer blade changes and more consistent cuts over a production run.

Common questions

How do I know this fits my machine?

If your current blade is the Z73, BLD-TZ129, or 500-9825, the K873 fits. It works in:

Zund G3, S3, and D3 cutters with the VCT1 and blade holder 5206262
Zund cutters with the T75 and V-cut insert 3102186
Kongsberg XL, XN, X, and V cutters with a PowerHead and V-Notch tool holder
Kongsberg C and XP cutters with an HD or Dual HD unit and V-Notch tool holder
Summa F Series cutters with a V-Cut Tool in the Tangential Module

Not sure which blade or holder you have? Contact us before ordering and we will confirm.

What materials does it cut?

Acoustic materials: PET felt, Zintra®, F-Sorb®, and polyester acoustic board
Foam and flexible materials: EVA foam, neoprene, foam, and cork
Foam boards: Foamboard, FOME-COR®, and Insite foamboard
Display and structural boards: Falconboard®, Reboard®, Zanita Board®, sandwich board, and DISPA®
Corrugated materials: B, C, E, F, and BC flute corrugated board
Other sheet materials: Corrugated plastic, matboard, cardstock, and cardboard

Cutting something not on this list? Reach out. We have probably seen the application before.

What is the difference between the K873 and the K773?

Both blades share the same outline and dimensions and fit the same holders. The K773 cuts on the bottom edge only. The K873 adds cutting edges on both angled sides, which lowers entry force and deflection. Choose the K873 for dense felt, foam, and heavy board. For general V-cutting, the K773 does the job.

How do I know when to replace it?

Watch the cut quality. Rough bevels, dragging, fibers pulling instead of separating, or torn corners all mean it is time for a fresh blade.

Getting the most from your cutting table

A fresh blade is a good start. But if you are going through blades faster than expected, or cut quality has become inconsistent, the blade is rarely the whole story. Blade exposure, cutting angle, speed, depth, material hold-down, and machine condition all affect how long a blade lasts and how clean it cuts.

It is worth asking: When was your machine last serviced? Are your parameters dialed in for this material? Is the V-cut tool calibrated correctly? Is this the right blade geometry for what you are cutting? Could your operators use time with someone who runs these machines every day?

Flatbed Tools offers machine service, preventive maintenance, operator training, and workflow consulting. If something is not cutting right, reach out. We have probably seen it before.