Why can't I burn my screens correctly?Updated 2 days ago

Screens can be a major pain point for many screen printers. There are a lot of variables that can contribute to a "bad burn", and we'll break some of them down here. If you're having continued issues with burning your screens, and this guide doesn't help you narrow down the issue, please reach out to our team and we'll be happy to help!

My Emulsion Isn't Sticking to the Mesh:

• Let's look at your prep first. Are you using the three step method when you reclaim a screen? Emulsion Remover, Dehazer, then Degreaser. The degreaser is especially important as it can remove oils, dirt, and anything left behind on the mesh. This step is even important when you receive a brand new screen!
• Have you used an Exposure Calculator? If so, what are your readings? A properly burned screen will wash out to the seventh mark on the exposure calculator. Underexposed screens will bubble and release from the mesh during rinse out. You’d be able to wash past the seventh mark on the calculator. This is an essential step for dialing in your exposure unit time.
• What side of the screen did you spray out when washing out the uncured emulsion? Only spray out from the t-shirt side. Spraying out from the squeegee side may cause the emulsion to release from the mesh, and make it weaker on the side that will be exposed to ink and the pressure from the squeegee.
• Where do you keep your emulsion when not in use, and how old is it? Most emulsions have a limited shelf life, especially when they require Diazo, but this shelf life can be cut even shorter by high temperatures. If you're in a space that doesn't have air conditioning, it might be a good idea to store that emulsion in a cooler place like a mini fridge. Just make sure not to freeze it!

My Emulsion Won't Spray Out:

• Hold your transparencies up to the light? Can you see light coming through the black ink? If so, your transparencies might not be dark enough. You want to make sure you are using the highest ink deposit settings on your printer if you are getting faint transparencies, or double up if you can by taping one transparency over another. You have to be very careful with this method to line them up perfectly to avoid any fuzzy edges, and this is not recommended for printing half tones transparencies. If you can't upgrade to an all-black printer, you may be able to find a print shop locally that can print your films, or you can order them from our partner at https://burnmyscreen.com/.
• When you use an Exposure Calculator, what readings are you getting? Overexposed screens will not completely wash out finer detail. You’ll also know it’s overexposed if you can’t wash out to the seventh mark. 
• What is your exposure set up? Do you have an exposure unit? Are you using sunlight? There are many different ways to expose a screen, but it's always important that the transparency is making direct positive contact with the screen. If you do not have enough positive contact between the film, the glass, and the emulsion, light can creep around the edges and make the image very difficult or impossible to spray out. Sunlight can be a very difficult way to expose a screen, and I'd recommend upgrading to a small exposure light or unit instead.
• What does your dark room set up look like? Is there any chance light is creeping in? Light leakage will pre-expose the surface of the emulsion, making it close to impossible to spray out an image.
• Did you bring the screen out into direct light at any point? Direct light will pre-expose the emulsion, making it close to impossible to spray out an image. You'll hear varying schools of thought on if you can apply emulsion in lighted environments to a screen, but it's best to keep it all in the dark room if possible!
• How long ago did you coat the screen you are exposing? Coated screens have a shelf life of up to six weeks. We usually advise to not keep a screen coated for more than four weeks to make sure they are always in optimal condition. 
• Does your washout booth have a pressure washer? A shower head type faucet can work, but it will take longer to break down the uncured emulsion. Do not scratch and pick at the emulsion other than a light rubbing touch as the water hits it. Too much rubbing, scouring, scrubbing can all break down your emulsion. Be careful with your pressure washer, you want a lower psi around 2000, and you want to keep the nozzle at least a foot away from your screen to avoid creating tears, pinholes, or blow outs on your screen.