Preliminary Sketch

[Polarity]

Ha

Me and my big mouth!.. I thought that the hull form would be the one I had already from Will... Nope! ah well its on its way but like everything to do with boats it will take 3 times as long as I thought!

Paul

[Willallison]

The hullform I originally posted should ony need minor 'tweaking' to fit this latest sketch. A little more rake in the bow and some alterations to the transom area....
But surely there must be some darts about to hurl at that hullform - I couldn't have got it right 1st go surely!!
Looking fwd to your post Paul....

[duluthboats]

No darts to throw Will, just wanted to bring this back up. Maybe some of the new members would like to join in. Please,
Gary

[sailvayu]

OK as the new guy I'll trough in my 2 cents. First i like the 2nd sketh better, still needs some work though. I think you need to get your engines lower in the water, may be just the sketch but I'd check this. You can get good info from the manuf. or from ABYC, I would strongly recomend the latter, as they set the standards. If need be I can send you a copy. Also I would recomend canvas for the overhang, it will save weight, you could zip on an extension for bad days or fold it up on nice ones. I have not seen any hydrosatic data If it were me this is were I would start then tune the Looks to fit. It would look to me thet the LCB is to far aft, the out boards will help but I would look at this carefully it's not always easy to move wieghts around. I don't know about other countries but here in the US you could go to a 10' beam, and maybe as far as 12 depending on the state, but at least 10. If you have some prelim lines and want me to run them through some hydro software let me know. If it were me I'd be focusing on that part first. Hope some of this helps, Looks like you'll get the first cyber design boat

[Willallison]

1st up, welcome to the discussion Sailvayu.
You make some good points - lets go thru them...
Its entirely possible that the engine height is way off - the drawing is little more than a napkin sketch to toss some ideas around regarding styling and accomodation plans. Personally I'd be inclined to go for a long-shaft o/b - maybe even extra-long. It raises the CG a little but keeps the powerhead clear of any unwanted wave action. On the downside it makes shielding the noise more difficult.
The canvas o/hang is an interesting idea. As you say it would reduce weight (and up high too). It could complicate the canvas structure somewhat - requiring more hoops and stuff. I guess it might depend on where and how you were planning to use the boat - some would prefer the o/hang, some wouldn't, but in general I think it's a good idea.
I've posted a few images of a possible hullform previously - though this requires some alterations as both bow and stern are slightly different now. In the preliminary hydrostatics, however the LCB lies about 63% aft.......
Take a look at the images and let us know your thoughts - you'll find a number of them in the "Gallery" and maybe a few more in previous O-1 threads.
As far as the beam goes, one of O-1's requirements was that it be legally and easily trailerable worldwide. Alas, that effectively restricts beam to 2.5metres.
Good to have you onboard and look forward to hearing more from you....

[Willallison]

Ok,
I've tweaked the lines a little to reflect the altered bow and transom shapes.

As drawn, the lines produce the following:

LWL 8.5m
BWL 2.09m
Draft 0.3m
Displacement 2060kg
LCB 63.8% of LWL
LCF 62.7 %
AWP 11.7 sq.m
Wetted Surface 13 sq.m
GMt 1.6m
GMl 25.8m

Coefficients:
waterplane 0.66
prismatic 0.62
block 0.38
midsection 0.61
displacement/length 93.4

There's no doubt a little more fine tuning to be done - what do you think?

And surely there must be some more changes for the preliminary profile and arrangement that I posted some time ago.....

[Polarity]

Hi Will

- looks almost what I ended up with from your sketch!
Is she still developable in flat panel ? looks like a complex curve / tumble home aft....
Could you send me that file please and I will try and shoehorn some time into it. - Amongst otherthings we have just opened a 2nd office in Palma so life is a bit hectic - have not even been working on my boat!

Cheers!

Paul

[Willallison]

File is on the way Paul

Should still be developable - there isn't any tumblehome - must just be the angle of the render that I captured.

As for 'no time to work on your boat' - I think you need to re-assess your priorities!!

[Polarity]

Thanks Will got that. Sorted out the minor dock damage on the bow there
Did have another go at my own Option 1 - presently looks like a hybrid gentlemans launch and a Tug might need some work !

Paul

[Willallison]

No sense hurling darts at yourself Paul - that's what we're here for! Show us what you got.....

Hi Will,

It's Tom L on the road and not posting for a while. There is no particular problem with having tumblehome and flare on the sides of developable surfaces. My boat has them and I think they add to the appeal of some boats.

One point made by Sailvayu is very mportant. I think that much of what has been done so far has been in the styling and interior decorating area. This is the tail wagging the dog to some extent.

Calculating the numbers as you have just done and then making sure that the rest of the work does not compromise these factors too much is vital if the design is to make any sense. Trying to fit in things that will have to be taken out later because they don't fit into the concept is the wrong way round. Maybe the group design is impossible anyway because someone is always taking off on a tangent that has already been discarded as not compatible to the original objectives.

Not to be too negative, I think that we should not drop the project because it has introduced some very useful bones into the stew. Gotta go.

[Polarity]

Ok Will et al, you asked for it!

Like I said, just an idea!

http://www.boatdesign.net/gallery/sh...papass=&sort=1

I droped my tug/gents-yacht cabin onto Will's hull (sorry Will!)
The wood was just the first texture I grabbed - Im not suggesting cold moulding!

Paul

[Willallison]

Polarity:
Love the pretty pics - would even go so far as to say that I like the varnished timber topsides - but I'll let one you traditionalists maintain all that brightwork....

Not too keen on the angle of the cabin roof- looks a little high at the back end.....
And without arrangement drawings it's a little hard to tell, but you don't seem to have left enough room for the head - which, by voters decree, is to be located on the same level as the main cabin / helm etc.

Otherwise, Bravo for a new approach

[Polarity]

Cheers Will
Wanted to see if everyone said "EEEUGH" before I put in the arrangement..!

[Willallison]

Nothing new from me I'm afraid - just wanted to bring the idea back up front.
Here are the hydrostatics of the hullform I posted before (same thread, earlier post). Any thoughts on how the numbers look?

LWL 8.5m
BWL 2.09m
Draft 0.3m
Displacement 2060kg
LCB 63.8% of LWL
LCF 62.7 %
AWP 11.7 sq.m
Wetted Surface 13 sq.m
GMt 1.6m
GMl 25.8m

Coefficients:
waterplane 0.66
prismatic 0.62
block 0.38
midsection 0.61
displacement/length 93.4