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Sorting Out Squeegee Sharpeners

(December 2013) posted on Wed Dec 18, 2013

Use this tool to restore the squeegee blade’s edge, so your squeegee can be brought back to action.

By Screen Printing's Solution Sourcebook

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Ground urethane can become lodged in the abrasives embedded in the grinding belt. When enough squeegee material builds up on the belt, the machine may grind erratically or ineffectively. Rogers says lack of a uniform grind across the blade and a reduction in material removal are tell-tale signs of urethane buildup on the grinding belt.

Wheel-based sharpeners (Figure 2) are engineered to be faster, more consistent, and easier to use. The grinder may be a stone, diamond wheel, or an abrasive belt wrapped around a wheel. Diamond wheels, for example, can be manufactured to produce certain blade profiles and changed out as necessary (Figure 3). Diamond wheels are designed to wear at a slower rate than stones, but both should be routinely checked for proper alignment. As is the case with long- and short-belt machines, the belt-wrapped wheel can generate excessive heat and lose efficiency as blade materials build up on the belt.

Manufacturers have added features and functions to the squeegee grinders in order to deal with temperature management, debris removal, and squeegee-blade handling. Cooled pulleys and tooling or machine components designed to naturally dissipate heat are some of the tactics used to prevent temperatures from climbing too high. Vacuum systems are integrated in some units to help remove urethane dust and particulates and prevent them from clogging the grinding media. In some cases, the operator need only attach a vacuum cleaner to a port. Finally, mechanical and pneumatic clamps are used to hold the squeegee blade steady during grinding, thereby further ensuring the production of a straight edge and uniform height.

Squeegee cutters
Squeegee cutters use knives, either stationary or rotating, to remove material. Some machines heat the knives to aid the cutting process. These knives are heated to 120-130°F, a bit more than half as hot as the melting point of the squeegee-blade material.

Cold-knife machines may come standard with cooling/lubricating systems to aid the cutting process and prevent problems associated heat buildup from occurring. Some squeegee cutters use knives that can be bought at hardware and grocery stores, such as carpet blades and injector-style razor blades. Other units require the use of proprietary blade systems. Either way, these machines can remove squeegee-blade material without generating dust and debris. That attribute makes squeegee cutters popular in industrial and specialty screen-printing operations in which production must be confined to a clean room.

