Hi everyone, I use x-rays for templates as well as stiffing something, but I clean them first. I'm not sure what you call the stuff in America or other countries, but we have a whitening agent called, Jik here in RSA. You use it to whiten your dishcloths. Put a cup full in some water and lay the dishcloth in it and it comes out sparkling white after you washed it, (I'm not trying to advertise) but be care full , it is quite strong on your hands. In any case, I use this "Jik" on a sponge and you can whipe the x-ray clear of all ink and it is completely see-through afterwards. I hope I explained it clear enough and that you will know what I am talking about. Remember to wash the x ray afterwards with soapy water.