Hull Blueprinting/Bottom Truing

[croSSed]

I used the search function for this one. There are a lot of threads where people have done this or are doing this, but I can't find any resources on how to actually do this. Can someone point me in this direction? A couple of questions: Is it possible to true a bottom with it on the trailer, not upside down? I suppose it would be if you didn't have to add any material, just sand it away. If you sand and break the gelcoat glaze on a boat bottom, does it make the boat faster? I have some experience with porting heads on high-po street cars. You don't want your ports to be too smooth or ports actually become kind of "sticky", slowing the air/fuel mixture down the port. I'm thinking the same thing is true of a boat bottom: a super smooth bottom would actually be kind of sticky on the water, where a slightly roughed up surface would be more slippery. Thoughts? Thanks for any insight!

TG

[staylor]

...and really not worth it if you're not already running 70+ or so. In general, it involves getting the bottom very staight in the fore and aft direction over the last 4 feet or so of running surface- and- getting all rounded corners along the strakes and pad made sharp, along with the entire width of the transom. Normally, you will have to build the hull up if the hook or rocker is more than a 1/16 inch or so. This must be done with care- since some boats have a hook or rocker added at the factory to cure handling issues. Each hull is different in what it requires, and the first thing to do is to flip the boat over, support it at several places so that nothing is being flexed, and start measuring with a 6 ft long straight edge. This survey of the bottom will usually tell you what must be done. If you're running at 80+, you may see a small gain from lightly sanding- actually just scuffing- the actual running surface with 320-400 grit wet paper- drawing the paper only in the fore and aft direction. Others here may have slightly different opinions and methods, but these are the general points. There are a few books that have been written over the years with articles on how to do this. Your're right about not much being on line. Maybe this is becoming a bit of a lost art.
Doug

[croSSed]

...Oh. I won't touch it then. I'll be doing well to crack 60 with my set-up. Thanks!

TG