UK-Cherub Forum

Cherub Chat => Sailing Stories => Topic started by: daryl_wilkinson on July 04, 2008, 10:01:03 AM

Title: pictures of Dan's boat...
Post by: daryl_wilkinson on July 04, 2008, 10:01:03 AM: Come on Dan, post them!
Title: Re: pictures of Dan's boat...
Post by: daniel_kemble on July 04, 2008, 04:53:50 PM: Patience . All will be revealed soon
Title: Re: pictures of Dan's boat...
Post by: Will_Lee on July 15, 2008, 10:29:52 AM: Here is one.
Title: Re: pictures of Dan's boat...
Post by: phil_kirk on July 15, 2008, 12:49:56 PM: It looks nice but I am not sure if the gantry/transom is in the spirit of the class rules. Has a measurement ruling been made?
Title: Re: pictures of Dan's boat...
Post by: Tim Noyce on July 15, 2008, 08:24:15 PM: In fairness, if you are sitting far enough back to have any of that in the water then you'll be going sloooooooooow.
Title: Re: pictures of Dan's boat...
Post by: mike_cooke on July 15, 2008, 10:00:56 PM: Quote from: phil_kirk on July 15, 2008, 12:49:56 PM
It looks nice but I am not sure if the gantry/transom is in the spirit of the class rules. Has a measurement ruling been made?

I cant see why it wouldn't be - its not fair with the bottom of the boat and loads of other boats have them in a similar style...
Title: Re: pictures of Dan's boat...
Post by: phil_kirk on July 16, 2008, 12:32:53 PM: I was not passing judgement of weather the boat is legal or not. I will let the measurers do that.

I understand that any surface that manages to deflect rising spray back down, by newtons laws of phyisics, is being lifted by the equal and opposite force. Rounded hull shapes do this less than flatt bottomed boats and if anything tend to deflect water sideways if at all. This is why we go for flatter aft sections on planing hull forms. I made a rudder stock for the Enterprise which has a small flange along the bottom edge. It did not continue the line of the hull but did manage to turn the wake that reached the bottom of the stock. The very small effect was not quantifiable but in theory should have been helping.

In a planing mode I suspect there is little gain with this gantry because the area of hull supporting the boat decreases as speed increases. more area is unecessary. In displacment mode, despite the step the water might be fooled into thinking that the boat is longer allowing a slightly higher hull speed. As with my rudder stock the effect may not be noticeable.

I would be interested in seeing some 'Rack Cam' footage of the wake coming of the transom and comparing this with similar footage from a boat with a smaller gantry. couple that with gps info at the same time and we should have a clear answer.
Title: Re: pictures of Dan's boat...
Post by: Phil Alderson on July 16, 2008, 12:44:45 PM: Quote from: phil_kirk on July 15, 2008, 12:49:56 PM
It looks nice but I am not sure if the gantry/transom is in the spirit of the class rules. Has a measurement ruling been made?

As far as I know the boat has yet to be measured and no one has asked any questions about it. I do not think you can tell anything from that picture.