Subject: Re: [harryproa] Re: harriette |
From: Mike Crawford |
Date: 6/15/2009, 12:40 PM |
To: harryproa@yahoogroups.com.au |
Reply-to: harryproa@yahoogroups.com.au |
Doug,
While I'm not sold on Robert's reverse sheer idea (I like the egg
cross section -- to each his own), I do think he has a point here.
To test his theory, I'd cut two short hulls from scrap foam (30 cm
and 45 cm each) and make some beams out of dowels or pencils.
For the first test, attach the beams parallel for one test, buried
into the hull pieces by at least 2 cm, and see how they will slide into
and out of the holds in the foam.
For the second test, attach the beams at a 30 to 45 degree angle,
again with 2 cm bury, and then see how smoothly you can get them to
slide in and out of the holes when both "beams" are in. I realize you
probably won't toe the beams out at 45 degrees, but the point is to
test the theory.
In the end, I think you'll find that: a) either the beams need to be
parallel, or b) the ends of the beams need to be parallel, even if the
main portion of the beam angles out.
- Mike
Doug Haines wrote:
Still not sure...sidecar is a cruiser, harriwette isn't.I have two boats, one is for sale.The easy moving to and from the water/beach is the main point of having a small one, so I'm trying to inmprove that part some more.Pretty easy, if you can see making in demountable with the beams at right angles, just turn everything on and angle and the beams where the rudders are can work further aft.So its a two part job, making demountable and while doing so putting the leeward attachment point further back - hence beams will be splayed slightly (same as toed?).It is fun trying stuff on the small boat, should really make some models.Mostly the sailversus underwater resistance laterally balance.Realised the other day that it would bealance better if the front rudder was actually up, hough I imagined the extra boards down owuld keep it straighter!How do you know how much total board area is going to be enough?I s related to speed or is that just the turning effect of a rudder that works better at higher speed?DougWhere's tsst proa got to?BTW, how about Capt Raps?