Pressure plates KP10 black

Pressure Plates KP10 are round plates in polyethylene (PE) that are fitted on the screw end of a locking knob and give a flat, gentle contact face against the material. When the knob is tightened the clamping force is spread over the 22 mm diameter of the plate instead of being concentrated in the end of the screw; that protects the surface of the work piece and at the same time gives a steadier grip against flat parts. There are two versions, one for M6 thread and one for M8.

Anyone who has built fixtures recognizes the problem the plate solves. A screw end that presses straight against the material leaves marks in paint, anodizing and softer materials, and when the screw rotates during tightening it can also twist the part out of position. With a pressure plate in between the contact is in plastic instead of steel, and the risk of the part being damaged or moving drops noticeably.

Polyethylene is chosen with care for the job. The material is softer than practically everything you clamp against, so it gives way before the work piece does; at the same time it is tough enough to take the clamping force without cracking. PE also has good chemical resistance to cutting fluids, oils and cleaning agents found around fixtures, and it absorbs practically no moisture. The plate is black with a matte surface.

The two versions differ in the hole: 6 mm for M6 thread and 8 mm for M8. The diameter of 22 mm is common to both. Match the plate to the thread of the knob or screw and check in the manufacturer's data sheet how the mount is shaped; the data sheet reports the detail dimensions for both versions. As a complement to three-spoke locking knobs in M8, for example our R53 series, the M8 plate is the natural choice.

The uses in Swedish workshop industry are many: clamping fixtures on drilling and milling tables where painted or finished surfaces have to be clamped, jigs in the wood industry, test setups in laboratories where delicate samples are fixed, and adjustable stops where the screw end would otherwise dig into the stop face. Pressure plates are used in shop and exhibition stands as well, when clamps have to hold without marking the surface finish.

The pressure plate is a wear part, and that is part of the point. After many clamping cycles against sharp or rough surfaces the plastic surface gets worn, and then you change the plate at a low cost instead of the screw or the material having taken the beating. It is worth keeping a few spares in the fixture store; it is the type of part that stops a job entirely for no good reason when it is missing.

When fitting, the plate should sit so that it lies flat against the material when the knob is tightened. Check that the thread length of the screw reaches through the knob and into the plate without bottoming out, and that the clamping force lands centered. There is no more to it than that; the simplicity is the whole idea of the part.

The plate also has a function in the clamping sequence itself. Since the plastic surface has higher friction against the material than a steel point, the part sits still already at low torque, and you can clamp in several steps without the work piece creeping between tightenings. When lining parts up against a stop that is a property that saves both time and scrapped blanks; the part lands right the first time and stays there. It shows in particular in fixtures where the same clamping sequence is repeated all day.

Questions about the fit against your locking knob or your screw? Get in touch with us and we will help you get it right.