It is safe to assume that all prep work will take roughly 2 days. Sometimes it can be finished in less time than that, but on average, you can expect it to take 2 days.
When you think your substrate surface is ready to go, take a 2 inch throw away chip brush, and apply some 2 inch by 2 inch patches onto your prepared substrate. Look for any variations in color or texture of surface and put a patch in those areas. Apply the patches when you will be able to let them sit for 8 to 10 hours. By then the Durabak will be dried and starting to cure-out, and should be like a very stiff rubber band. Place a pocket knife blade into the middle of a Durabak patch just under the Durabak coating (about a ¼”) on top of the substrate, and pull straight up. The Durabak material will stretch like a stiff rubber band. What you want to see is the material stretch roughly 1/16” to 1/8” and then your knife blade should eventually cut through the material. If this happens, you are ready to go.
If the patch peels up, look at the back side. You will see one of two things: either it will have a lot of dust and debris on it (in which case you would need to re-clean the area) or the back side will be very shiny.
If it is shiny: rub your finger on the shiny surface and you will find that the surface is either shiny and dry, or shiny and slimy.
If the surface is shiny and dry, apply a water based urethane primer on only that area of the substrate.
If it is shiny and slimy however, either the surface needs to be re-cleaned, or there is oil in your substrate, and an oil or solvent based urethane primer must be used.
Please test all projects before the application, because it may save you from unknown problems. Our goal is for you to have a great project to remember, not one that requires extensive reworking.