Here's a tip for getting some letterpress roller coasting love. We take something into our press room from the pitchers mound - a rosin bag. You can get them at your local sporting goods store and they should cost only a few dollars. A rosin bag will change your life when printing on a Heidelberg Windmill. This is one mysterious fine white powder that won't get you into trouble. As a derivative of pine sap, rosin is valued for it's friction increasing properties. The rails on a windmill - or any platen press for that matter - must be clean and oil free. Any lube on your rail track can create ink slurring as the rollers comes into contact with the surface of your form. It can be very slight, but noticeable if you look at your printing under a loupe. We are all about having as crisp and clear a transfer type and image as possible. After the rails have been cleaned well with alcohol, a few small taps with the rosin bag down the roller rail track will transfer some powder and create additional grip as the roller trucks move over the rail. Don't use too much, you don't want it to build up and create little gobbers and bumps. If you have your roller height set correctly, this little bit of extra friction will help your rollers sail over your printing form.