Hydraulic Shear Setup for Narrow Strips

Usable narrow-strip blanks require more than correct width: the sheared edge and strip shape must also suit the next forming operation. Evaluate the material, approved blade clearance, available rake adjustment, workholding and support together, then judge representative strips against the profile they must become.

The HOCHSTRATE HYDRAULIC PLATE SHEAR is worth evaluating for recurring channel, angle and architectural-profile blanks prepared from flat sheet stock, provided the selected machine covers the material and full cut length. Its straight-blade process separates stock with a moving blade passing a fixed blade.

Width, edge condition and strip shape

The backgauge establishes the positioning reference for cut width. It does not establish whether the separated strip has acceptable burr, straightness or flatness. Treat dimensional positioning, edge condition and strip shape as separate application questions.

Bow curves the strip out of its original sheet plane; twist produces a spiral along it; camber curves it within the sheet plane. Distortion tends to increase as strip width decreases relative to thickness, and longer cuts can also increase distortion. A wide demonstration blank is therefore not an adequate substitute for the narrow, long blank required in production.

Shearing can also release stresses already present in the sheet. Better settings should not be treated as a promise that every strip will remain flat. The useful question is whether the resulting blank meets the actual forming requirement.

Clearance and rake solve different problems

Blade clearance is the separation between the passing cutting blades. The appropriate setting depends on the material and equipment; unsuitable clearance and dull blades can impair the edge. Use the selected machine’s approved settings rather than applying one clearance percentage to every alloy and thickness.

Rake, or shear angle, is the slope of the moving blade across the cut length. Lower rake engages more material simultaneously and increases the cutting force required. A lesser angle can reduce deformation on thin sheet, but this is a force-versus-distortion tradeoff—not an unrestricted quality adjustment. The permitted setting must remain within the selected machine’s capacity and operating instructions.

The HOCHSTRATE family offers cutting-angle and blade-gap adjustment choices, including automatic cutting-angle adjustment and motorized blade-gap adjustment. Confirm their inclusion and permitted ranges in the quoted package. For a changing material mix, compare the available adjustment method with the frequency of setting changes; an option matters only if it addresses the workload.

These process principles explain what to assess, not how to adjust a particular HOCHSTRATE machine. The supplied model manual and qualified personnel must govern adjustment procedures.

Hold-downs retain the feed stock

The HOCHSTRATE family has a continuous automatic hold-down close to the knife. Its job is to retain the feed stock on the table during cutting; that is different from controlling the shape of the strip after separation. Motorized backgauging and hydraulic sheet support are configuration choices whose inclusion needs confirmation.

The distinction becomes important as repeated cuts leave a narrow remnant on the feed table. Inadequately clamped narrow stock can lift during cutting and re-clamp afterward, creating a pinching hazard. Evaluate how much stock remains under the hold-down and whether it can be safely positioned—not just whether the gauge can reach the requested strip width.

Sheet support should be evaluated with the actual stock and intended handling method. Support must not depend on reaching beneath guards or into the blade or hold-down area. Point-of-operation safeguarding remains necessary during cutting. Servicing that exposes personnel to unexpected startup or release of stored energy requires the applicable hazardous-energy controls; support accessories do not replace those protections.

Match the configuration to the material

Repeated rectangular strip blanks are a relevant application only within the selected machine’s documented material and cut-length rating. Architectural aluminum work also warrants evaluating alloy, temper and finish: aluminum-specific blades and surface-protecting support choices are available, but those options do not establish capacity for every aluminum job.

Stainless stock needs its own capacity assessment rather than an inherited mild-steel thickness rating. In austenitic stainless, shearing-induced work hardening can contribute to cracks originating at the cut edge during subsequent bending. Evaluate the edge through the intended bend, not solely by its appearance after cutting.

The HOCHSTRATE family’s published thickness coverage begins at 1 mm. Roofing or HVAC stock below that thickness needs configuration-specific confirmation before this machine is considered suitable. A family envelope is not the complete rating of the machine being quoted.

Judge the blank in its formed profile

A useful application trial should use representative production stock, including the narrowest strips and longest cuts being considered. Define width variation, straightness, flatness, burr and finish requirements from the finished-profile drawing and the next forming operation.

Carry the trial blanks through that operation in the required material orientation. Record both the strip measurements and the resulting profile. This proposed evaluation separates a positioning concern from an edge or shape concern and provides a more useful basis for comparing configurations than a nominal width measurement alone.

Batch size and the frequency of material changes should guide the value placed on positioning, adjustment and support equipment. Select those features around recurring usable blanks, without assuming a cycle-time saving or a guaranteed minimum strip width.

I’m Patrick O’Neill, Mac-Tech’s National Product Manager / Regional Sales Executive serving the U.S. market. I can help relate your blank geometry, material orientation and forming requirements to the proposed shear’s configuration boundaries. Call me with the strip and finished-profile drawings, material grade or alloy and temper, actual thickness, narrowest width, longest cut and current samples if available. I can work with you and Mac-Tech to assess permitted adjustment options, workholding, support and documented capacity around the blanks you need to form.