Hacker hull: No deadrise >> A little more

This is a long, long term project that is really just a lunch hour hobby right now. I have the loftings for John Hacker's White Cap. A 25', 1930's classic runabout design. I've ported them into Freeship to check the fairness of the hull (published numbers are actually pretty good. Just a 1/8" here, 1/4" there for correction - certainly close enough to compensate for on a lofting table). I've already done a trial porting into Pro/E via IGES for creation of rib profiles and patterns.

The specific question is around deadrise. The as-published loftings have a 0* deadrise at the transom. A variety of sources seam to indicate that between 5* and 7* is just fine to smooth out the ride and not be too detrimental to power requirements. Remember this is an inland lake boat, not intended for open water.

Freeship indicates the longitudinal center of buoyancy moves aft by about 4". For a 25' boat, this seams to be inconsequential. If/when I get around to actually cutting wood, all I'd do is probably put in a bigger gas tank to compensate and maybe move the engine aft a few inches. Any comments?

Is there any way to check the planing trim of the hull?

 

So it's not a Hacker sledge, with negative deadrise?

 

No, the "White Cap"

 

Sorry, that was Hickman...

 

Well, my opinion is that in protected waters and modest speed a flat bottom in the after part is OK.