If you have it that far why not go ahead and throw a single coat of resin over the whole thing to seal it. It would bond any short fibers and seal off any porosities, or do you have any of those issues? Then block it down, then fair and prime. So patch , fair, prime. Start with 80 to even it up, 36 is too much except where you need to remove a lot of material fast. Follow the directions on the primer to get the proper grit before priming for the best adhesion.
Quote from: "slvrlng"If you have it that far why not go ahead and throw a single coat of resin over the whole thing to seal it. It would bond any short fibers and seal off any porosities, or do you have any of those issues? Then block it down, then fair and prime. So patch , fair, prime. Start with 80 to even it up, 36 is too much except where you need to remove a lot of material fast. Follow the directions on the primer to get the proper grit before priming for the best adhesion.when you say throw a single coat on, do you mean just roll a coat of resing on it? I do have exposed fibers and porus spots so it makes sense and it seems it would fill alot of the sanding marks and such.
Oldskool,I would not recommend coating the whole boat in epoxy or poly resin, as that is simply creating another bout of sanding the entire hull and accomplishes little. Straight resin is not a good fairing or priming compound. Plus, sanding straight epoxy resin is a painful process. Please remember that you are adhering layers based on mechanical bonds created by sanding, not chemical bonds between wet laminates in succession.There is a big difference between fair and smooth. You can have a smooth surface that will shine like a gold tooth when painted, but may have underlying dips/waves that are not fair at all. Concentrate on fairing first. Therefore, you will first make the spot repairs that have to be addressed and then longboard them fair w/ 80. Blue dye/tooling dye thinned 80-90% with denatured alcohol will certainly help you in identifying highs/lows. Wipe the area 2-3 ft beyond the repair first with the blue dye and longboard. The lows will stand out in blue. Then fill w/ fairing compound and repeat until fair. Then shoot the whole boat w/ high build primer and wipe down w/ tooling dye when dry. Londboard w/ 220 and fill the lows. This will take care of the small waves that will be all over these older hulls. Once filled and longboarded, hit w/ another coat of primer, dye, and hit w/ 320. Now you are fair and smooth. Shoot w/ paint at this point.You are welcome to swing by the shop this week to see some examples. We have one boat fully shot in primer ready for final sanding and painting. We also have a 4x4 ft repair on one of Pinellas County's 3 fireboats that we are finishing up. Seeing what the guys are doing on these 2 boats will give you a pretty good idea of the succession of steps to achieve both a fair and smooth hull prior to painting.