Squeegees and Your Printing Options

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Most in our industry will pinpoint the screen as the most important tool in the printing process, but the squeegee will come along as a close second. The squeegee, the durometer (hardness), the angle and the pressure will have the next greatest impact on the appearance of your final printed product.

In garment printing, the squeegee blade will most commonly be polyurethane. Blade material can be cut to your specified length, either by your supplier or by yourself in your own shop. For manual printing, the blade and squeegee holder are often cut to length in a single process from a larger fully assembled squeegee. Squeegee blade material is also readily available from suppliers for you to cut and attach to the handle yourself. Finished squeegees and separate blade materials are almost always purchased by the inch and to your specification.

Squeegees have several functions:
1.) Pushing ink through the screen and onto your garment. The amount of ink forced through the screen is determined by the mesh size and the ink viscosity (thickness).
2.) Causing the screen mesh to come into contact with the garment. This contact will also be affected by screen tension and the off-contact distance between the screen and the platen.
3.) Sheering the excess ink from the print area on your screen. By sheering away the ink from the print area, no ink is left in the screen that might pull the ink on the garment back up into the screen. Lack of proper sheering of the ink from the print area can cause an uneven lay down of ink and a rough surface to your finished print.

Durometer refers to the hardness of the squeegee. Durometer affects the amount of printing force you can apply to the screen and garment. Softer squeegees result in less force than harder ones. There are three most common categories of squeegee blade durometer.

  • Soft (approximately 60 durometer and below) squeegees will be used when you want a heavier lay down of ink. A soft durometer squeegee can be used for inks such as puffs, where a heavy deposit of ink is required to achieve the puff effect. You might also select a soft squeegee for fabrics that require a heavier deposit of ink such as fleece.
  • Medium (approximately 70 durometer) squeegees are a middle of the road option, and will be used for general printing. This will be the tool of choice for most of your day to day production.
  • Hard (approximately 80 durometer or higher) squeegees will lay down the least amount of ink and are most common for printing process and simulated process jobs when fine lines and halftone dots are needed. You might also select a hard squeegee based on the fabric substrate (such as nylon jacket material), where the ink will set on top of the fabric, and therefore require less ink for the job.
  • Multi-durometer squeegee blades (70/90/70 for example) are made of two or three layers of different durometer squeegee material. A harder blade will generally be sandwiched in the center of softer squeegee material to lessen the “give” of the blade. This layered blade is most common for process and simulated process work. The stiff center will help in the sheering of ink, while the softer outer edge will lay down slightly more ink. You’ll see these multi-durometer squeegees in many automatic shops, as well as manual shops for fine detail work.

Blade profile is the shape of the actual squeegee printing edge. A square profile is most common in garment printing, and provides the maximum ability to sheer the ink from the print area of the screen. Round squeegees provide a heavier lay down of ink. There was a time in textile printing when rounded blades were used for printing inks such as puffs, to maximize lay down of ink. Most printers today will opt for a softer but square edged blade for heavy ink deposits.

Pressure is the downward force you apply to the squeegee blade. In automatic printing, this is a set adjustment. In manual printing, it is a "feel" you will develop over time and with experience. There is a balance that must be achieved. You must apply enough pressure to sheer the ink from the screen, using only the sharp edge of the squeegee blade. Too much pressure and the blade will "roll over", and you will be printing with the flat side of the blade rather than the edge. The result will be either too much ink lay down, or ink being left in the print area of the screen instead of on the shirt. A softer squeegee blade will tend to "roll over" more than a harder blade.

Squeegee Care
It is important to thoroughly clean your squeegees. Most printers will clean the blade and handle with a solvent solution right after printing. Take extra care in cleaning the area where the blade meets the handle.

It's a good idea to reserve particular squeegees to be used with particular ink colors. This will save you spoiled shirts and spoiled ink when red ink from under the squeegee blade suddenly appears in the white ink in the screen.

If you use a solvent tank or tray, do not soak the blades for extended periods of time. This soaking of the blade material can cause swelling or distortion of the blade, ruining it for future use.

Store squeegees either on a hanging rack or in a handle down/blade up position on a shelf. Never store squeegees resting on the blade. The blade will eventually warp or distort and become useless.

If you discover nicks in the squeegee blade, showing up in your print as a heavier deposit line, you have two choices. You can sharpen the blade with either a professional sharpening device or a homemade sharpener created from fine sandpaper attached to a board. Or you can remove the blade from the handle and replace it with new blade material. Replacing the blade is the most common option.

Today, there are ergonomically shaped squeegees, blades created for pushing rather than pulling, and new approaches to the process with each coming trade show. But for now, the most common approach will be the standard wood handled device, chosen simply by the proper durometer to match your chosen ink and substrate.

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