Washing out PhotoMask™

Washing out resist requires a running water supply and a good trigger jet wash out spray. Almost all past customers who have not purchased the trigger jet waste film until they purchase one eventually.

A white backing board is the best to wash out on so that you can see clearly the washed away area. ProBlast sells a powder coated metal washout board with convenient magnetic clips for holding the resist.

Where to Wash out

You can wash out in any sink as long as there is no direct sunlight. You can not take the resist outside and wash it. The direct sunlight will ruin it.

If you are using a shallow sink you might consider having an Acrylic box made up as a cover for the sink so that you don't get water all over the room. These are simple to make and are worthwhile.

Some Factory units have disused showers, which make excellent wash out booths but a sink in a factory kitchen or a Laundry in a house works fine. Just remember - Block any direct sunlight.

What kind of water

Normal tap water is used for the washout process. We recommend that you use shower temperature water for the fastest and cleanest wash out. If you only have cold water you can still use this. Many people do. We advise against using completely hot water as this will cause slight melting and give you unstable resists.

How long should it take to wash out?

If you are washing out 80mm x 80mm it should take around 30 seconds to wash out. If it takes more like a minute then you may have over exposed the resist.

When washing out large sheets of resist keep the fine detail section at the top of the washout board as fine detail washes out faster than thicker artwork. This will prevent the over wash from saturating the fine area.

Washout Summary

• Use shower-temperature water. This temperature water will give you the fastest quality results. DO NOT USE HOT WATER. Above shower temperature water is too hot for the resist and slight melting may occur rounding of sharp edges and making the resist susceptible to blow outs. Cold water can safely be used but it takes a little longer.
  
  
• Use the ProBlast washout hose. Everyone that bypasses this product has trouble in the washout process. The ProBlast trigger Jet Washout Hose. It is the one recommended by Rayzist.
  
  
• Use the Krystal Kote Black art spray on you artwork vellum to further blacken the art. By doing this you are reducing the amount of light that gets through the black of the artwork rendering the artwork area less exposed. This in turn makes the washing process much faster.
  
  
• Have a white board as your backing board so that you can see clearly what is washed out and what is not. ProBlast sells a magnetic clip washout board that works well.
  
  
• Move around the resist with the water flow so to not stay too long in the one area, which may cause saturation of the resist and weaken it.
  
  
• Hold fine detail sections of the resist to the top to avoid over saturation. Fine detail art washes out quicker than thick text so if it's held on the washout board above the thick text then the water run off from the thick text washout won't saturate the fine detail section of the resist.

Drying the resist

It is important to wipe of excess water off the resist once the washout process is finished. For further details see the technical support document entitled 'Drying the Resist'.