Starting a screen print shop means investing in all sorts of equipment. One piece of equipment that printers tend to wait on is a pressure washer. But is a pressure washer worth investing in now rather than waiting and making do without? Here’s a guide to buying and using a pressure washer in a screen print shop.
WHO SHOULD USE A POWER WASHER?
Ideally, every shop should have a pressure washer in their shop. It speeds up the reclaim process, blasts away stuck emulsion and is just plain fun to use. However, not every shop needs a pressure washer in their reclaim setup. Shops that benefit most from having a pressure washer in their arsenal are shops with the right equipment and a higher production volume.
For printers just starting out, a high-pressure hose might do the trick. A garden hose can be a great solution, especially with a nozzle attachment. A high-pressure shower head may also work, though shower heads aren’t known to produce high-pressure water.
As a shop receives more and more orders, more screens need to be made and reclaimed at the end of a job. The more screens a shop needs to reclaim, the more important a pressure washer will become. Speeding up the reclaim process is important, especially with 25 screens to reclaim instead of 5.
Interested in upgrading to a pressure washer? First, upgrade your darkroom equipment. Use a washout booth and a filtration system. Washout booths come in many shapes and sizes. A filtration system — even a DIY setup with screen mesh and buckets — will help keep the shop’s pipes clean.
HOW TO USE A PRESSURE WASHER
Virtually all emulsion removers will give far better results with a pressure washer to blast away the eroded emulsion. Position the screen with the top edge against the back wall of the washout booth. Leaning the screen against the washout booth will provide support for the screen when it’s blasted with water. Apply emulsion remover to both sides of the screen, scrubbing it in circles with your scrub pad. Once the emulsion looks like it’s starting to loosen up, it’s time to put on the pressure.
Be sure the pressure washer is blasting the print side of the screen. A high-pressure spray directed at the squeegee side of the screen can hit the inside edges of the frame and ricochet. The point where the mesh meets the inside edge of the frame is also one of the most vulnerable points on your screen—the last place that ought to be hit with a high-pressure jet of water.
TIPS FOR USE
Here are some tips for getting the best results with a pressure washer, both during image rinse-out and screen reclaim.
When you’re rinsing out a design after exposure, slow and steady wins the race, turn the power down, widen the spray, take a step back, and blast the screen in slow movements. It’s important to keep in mind that emulsion is pretty soft at this stage, so too much pressure can risk knocking out the design’s edges or finer details.
Use a broad, fan-shaped spray to reclaim screens. A narrow spray delivered at full power can blast right through fine meshes. A wider spray will almost always work better unless small spots of old, hard-to-remove emulsion remain on the screen. In these cases, using a narrower, stronger stream around the edges of the problem areas should work. Think of it as using the water to ‘scrape’ the emulsion spot away.
For pressure washers with adjustable nozzles, get into the habit of aiming the wand away from the screen the first time you pull the trigger. This way, the width and power of the spray can be adjusted without harming the screen.
WHERE TO FIND A PRESSURE WASHER
Finding a pressure washer isn’t hard. Head to the local hardware or home improvement store (or shop online) to find one. Find one capable of at least 1200psi, though 1600psi is the most common. Both the power and width settings of the spray can be adjusted on most pressure washers.
Depending on the price point, there are a few options for a pressure washer. The highest-end pressure washers have different nozzle attachments, so printers can get that perfect fan shape every time. Less expensive models have one nozzle that allows adjustments to fine-tune the spray.
Not sure if a pressure washer would be beneficial? Try to reclaim some screens without it. If the reclaim process is taking way longer than it should, or the emulsion is putting up a fight, invest in a pressure washer.