Screw clamp (various sizes)

Cast iron screw clamp with profile steel rail according to DIN 5117

Various sizes ✓ Removable protective caps ✓ Ergonomic handle ✓

With the high-quality screw clamps from Högert, we offer the perfect tool for fixing in professional craftsman quality at an affordable price. The cast clamps with solid clamping arms and highly stable profile rail made of steel have a ball-bearing head for fixings up to an inclination deviation of approx. 35°. Thanks to the pronounced cross grooves, which are pressed into both sides of the profile rail, the Högert screw clamps always guarantee a secure hold. There is no risk of them loosening by themselves, even with comparatively low forces on the pressure plates. The blue plastic protective caps protect sensitive surfaces from damage due to scratching and can be removed if necessary. For safe handling, the twist grip is equipped with a rubberised surface to prevent slipping at high tightening torques.

We carry the screw clamps in different versions with different lengths of the profile rail, for different high clamping ranges for fixing. These are optionally available in 150mm, 250mm or 300mm lengths at reasonable prices. Furthermore, the clamping depths also vary, based on the length of the clamping arms from 50mm - 80mm.

Properties of the solid screw clamps

Only high-quality materials are used for Högert cast-iron screw clamps in order to meet the high quality requirements of the trade or workshop at all times. They are manufactured in accordance with the DIN 5117 standard for screw clamps. The profile rail is made of solid steel. Depending on the version, it has a length of 150mm, 250mm or 300mm, which provides information about the maximum clamping strength of the screw clamp. Due to the wear-resistant material, the screw clamp is characterised by an enormous service life and is enormously resistant to bending or damage.

The edges of the profiled steel rail are equipped with pronounced transverse grooves on both sides. These contribute to secure fixing, especially at high tightening torques, which occur with high clamping forces, so that the screw clamp cannot become loose or loosen due to shocks or vibrations. The notched depth limit at the outer end of the profile rail helps to ensure that the movable clamping arm does not slip out downwards when the clamp is opened. The width and thickness of the rail varies, depending on the chosen version. On the smaller clamps with 50mm clamping depth, the rail has a width of 15mm and a thickness of 5mm. On the larger screw clamp with a length of 300mm, the rail has a much more solid design with a thickness of 6mm and a width of 22mm. A groove stamped lengthwise on both sides not only increases stability but also reduces the weight of the tool.

A high quality screw clamp offers high clamping force and a durable construction that provides the necessary stability and control when working. The solid clamping arms are made of one casting, which ensures a very high clamping force without bending or warping. In addition, the robust construction has the advantage that the material can be held more firmly, which prevents it from moving while working. The length of the clamping arms provides information about the maximum reach for fixing objects. With the smaller screw clamps this is limited to 50mm. The larger screw clamp with a length of 300mm has a clamping arm length of 80mm. All screw clamps are equipped with removable protective caps made of robust plastic. These plastic caps are especially helpful for sensitive or painted surfaces and protect the objects from damage due to scratching.

The ergonomically shaped handle is easy to turn and has rubberised surfaces to prevent slipping when tightening or loosening the screw clamps. The coarse, solid steel thread is deeply embedded in the handle and slides effortlessly through the lower clamping arm, making fixing objects very easy and quick. A ball bearing on the lower, round head plate offers maximum flexibility and automatically adjusts to the material surface. This allows an inclination of the support surface of approx. 35° in all directions, so that fixing of objects on or with sloping edges is also possible.

Specific data of the different screw clamps

• Screw clamp 150x50mm: Depth clamping arm: 50mm, clamping length 150mm, pressure plate: 23mmx30mm / Ø22mm, weight: 345g
• Screw clamp 250x50mm: Depth clamping arm: 50mm, clamping length 250mm, pressure plate: 23mmx30mm / Ø22mm, weight: 390g
• Screw clamp 300x80mm: Depth clamping arm: 80mm, clamping length 300mm, pressure plate: 28mmx40mm / Ø28mm, weight: 815g

Use and handling of screw clamps

The basic principle of a screw clamp is as simple as it is ingenious. The objects to be fixed are positioned so that the clamp can be applied from both sides with the clamping arms. These must have at least enough contact with the surfaces so that the upper and lower pressure plates of the clamp are in full contact, so that the screw clamp does not slip off when it is tightened. It does not matter whether the clamp is only used for short-term fixing of boards for easier sawing or screwing, or for pressing together freshly glued substrates or as an assembly aid for heavy objects. Before attaching the clamp, the handle should be opened as far as possible until the ball head reaches the lower clamping arm. Then position the clamp in the desired position. The upper clamping arm is placed on the corresponding surface and then the movable lower arm is guided along the steel profile rail until the ball head makes contact with the opposite surface. The clamping arm should be pushed straight over the rail so that it does not get caught on the cross grooves and thus jam. Finally, by turning the ergonomic twist handle clockwise, the necessary firmness of the fixation can be established.

When the handle is tightened, the lower clamping arm tilts with the profile rail so that it no longer slips down. The transverse grooves along both edges of the solid steel rail increase the security against loosening enormously and hold the clamping arm safely and reliably in the desired position until the fixation is released again. How strong the pressure of the contact surfaces must be and how tightly the handle must be tightened for this depends on various factors. On the one hand, care must be taken that the surface of the object is not depressed by too high a clamping force, and on the other hand, the handle must be turned until the fixation reaches the desired strength that corresponds to the application purpose. For the short-term fixing of metal profiles that are to be welded afterwards, usually not too much clamping force is needed, whereas the screwing or gluing of wooden beams and boards with a slight bend requires a little more contact pressure until the wood glue has hardened or the screws have been screwed in.

To loosen the screw clamp, simply turn the handle slightly anti-clockwise until the lower clamping arm is loosened enough to allow it to be moved downwards. Especially when clamping fixations with objects under tension, which was created by the fixation, proceed carefully in order to reduce the risk of accidents due to a jerky release of the tension.

Application examples for screw clamps with rotary handle

• The screw clamps secure boards and beams against slipping when cutting with a saw
• Screw clamps are a good aid when installing façade panels and balcony cladding
• Screw clamps can be used to securely fix plastic joining parts for bonding or welding
• The robust clamp is ideal for quick, precise fastenings for gluing in joinery work
• Screw clamps are perfect for fixing steel profiles with millimetre precision in order to weld them
• Thanks to the high clamping force, the clamps are also suitable for materials that are under bending stress
• and many more

NOTE: For soft or very pressure-sensitive surfaces, the contact surface can be increased by using a plastic or wooden plate. This is inserted between the object and the screw clamp and distributes the pressure over a larger area. This little trick significantly reduces the risk of damage by pressing in the contact surfaces of the screw clamp. In the case of very scratch-sensitive surfaces, as well as lacquered or high-gloss surfaces, a soft cloth can be used as a further aid to prevent scratching and damage to the lacquer by placing it on the surface to protect it. This avoids direct contact between the screw clamp or wooden plate and the object.

Technical data of the cast screw clamps

• Material: Steel, cast iron
• Colour: Blue, black
• Clamping length: 150mm, 250mm or 300mm
• Clamping depth: 50mm resp. 80mm
• Top support (with protective cap): ca. 23mm x 30mm resp. ca. 28mm x 40mm
• Top support (without protective cap): ca. 19mm x 25mmm resp. ca. 25mm x 36mm
• Bottom support (with protective cap): Ø 22mm resp. Ø 28mm
• Bottom support (without protective cap): Ø 20mm resp. Ø 25mm
• Protective caps: Yes, removable
• Profile rail thickness: 15mm x 5mm resp. 22mm x 6mm
• Corrosion resistance Sufficient
• Rust resistance: Sufficient