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Messages - Derek

#46
PPOW is unusal in that it has a leeward finish. Do you know of any CLASS races that are NOT decided as first past the post??
 
Derek 3510
#47
Boats / Re: N3510 Silk Purse
05 Mar 2008, 02:14
See also November in the fotoboat calender for 2008.
Derek
#48
Boats / Re: N3148 Pillow Talk
05 Mar 2008, 02:12
Owned and sailed for a long time by John and Mandy Thornton.
Contact them for more details.
#49
Boats / Re: N3509 -
05 Mar 2008, 02:11
This is a fictitious boat as I bought a few numbers prior to 3510, my current boat number which happens to be 100 more than the first Foolish and 1000 more than my first N12 2510 a Rowsell built 7 plank China Doll.
there is no 3509 or 3508 or 3507 or 3425 come to that - if anyone want the numbers they are vacant.
#50
Boats / Re: N1710 Seventeen Ten
05 Mar 2008, 02:03
Was owned and sailed by Bridget Cooke in Exmouth in the mid 70s. It went to the 75 burton in Plymouth where crash tacks were performed to allow the crew to screw the (now) leeward shround plate back into place. Judging by condition then I doubt if it is still around!
Derek
#51
Boats / Re: N2750 Cheshire Cat
05 Mar 2008, 01:58
and still owned by the designer and original owner....unless someone knows otherwise. I think he still has March Hare too.
Derek
#52
Boats / Re: N3200 Baggins
05 Mar 2008, 01:55
For more info contact Kevan Bloor - it was his boat from new. I think it was a Cheshire dinghy and dive (Peacock) special which could be confirmed by checking plate width.
Derek
#53
There are actually at least 4 Freak Outs.

Beans, Arouser (renamed Mouser) 3396 Rob Peebles yellow soap dish configured Burton winner and 3406 Agent Orange.

As Meads says they are a derivative of D8 with less rocker and more beam aft.
They are therefore more sensitive to weight (the less rocker bit) but if sailed appropriately light can be faster downwind. Whether that is down to the weight or the rocker is another question...

All hulls were glass foam sandwich and made by Rowsell and Morrison.
Beans and Mouser were both finished by Kevin Driver.
Rob finished his and I finished 3406 as an amateur replica of the R&M type.

Strong point is light winds - very quick.

Weak points - wide, flat and shallow at the back so ships water tacking, particularly short tacking in tidal conditions where you tend to ship the whole of your quarter wake as you tack out from the shallows.

Marginal planing in waves is not so strong but seems OK on finer legs. Also quite reasonable uphill.

All except 3396 are wooden deck and varnished so reasonably pretty but rather more work than an all plastic D8.

Driver boats (being built by and for a Merlin sailor around 10 years ago are deck stepped.
The other two are more conventional.

Derek N3510
#54
What strikes me as strange in this debate is that the shape shown is intended to be a displacement hull, so intended for light weather or inland. The sections are almost parallel and look very skiff-like. This means lots of wetted area for the required displacement.
There is even less displacement when heeled than when upright so if you roll it to tack, it will stop because it will sink deeper into the water, the corner of the transom and probably the wing will dig in.
If you are seeking to make a displacement hull, more rocker and some move volume in the topsides around the crew c-of-g would help. This will lift the ends out when you tack, shortening the boat as it tacks and losing less speed as you drag the ends through the tack.
If you take the hull shape and work out where the design displacement puts the waterline with the sheerline on the water, it will show you how long the waterline is when you tack. Short is actually good for tacking!
Baggy has no displacement in the topsides and a very low sheer so hard to tack.
Modern boats have less rocker and so tend to be harder, or at least slower to tack.
A great favourite for inland sailing is Pipedream which has a fine U'd entry and a straight rocker forward but loads of bussle (rocker in the last ~3ft) and a fairly small transom together with good volume in the topsides around 8-9 ft from the bow.
If you can find one it would be worth a look.
Does anyone have a set of Pipedream lines?
#55
...and you can add to the list of designs getting top 10 places -
...."Bouncer" or something that once looked like Bouncer.
#56
Can I suggest you read sections on hollows and on gunwhale overhangs.
Unless things have changed you are not allowed any hollows aft of mid-length and the gunwhale overhang outboard of the sheerline its limited to 50mm.

The flare on this hull must be either hull or gunwhale so it must contravene one of those.

N12s are quite good at getting minimum waterline beam on a 2m wide hull with no hollows. It is one of the main challenges of the design. Another constraint to look out for is the rise of floor which whilst intended initially to avoid boats becoming overly narrow on the waterline, now measures a point about 35mm above the design waterline. Most hulls are spot in the minimum rise of floor by design and some are bumped to meet it. Feeling Foolish is a notable exception.

The "no hollows" rule was (I think) introduced to prevent the need for expensive cold moulded boats and was prompted by the arrival of the 505 with its flared topsides. (Makes it a late '50s rule).
Since we no longer have anything in the rules about "catering for those of limited means" (which was in the first couple of lines of the rules initially) and since we can mould concave surfaces as easily as convex ones, perhaps we should think about deleting the hollows rule.
It would make for a more interesting looking boat - only time will tell if it is faster but it would be interesting to allow someone to try it!
#57
Given that Pitsford was nice and calm, and my daughter Tori was doing her first full open, most of you probably heard first-and some of my "suggestions" on what crews should do.
That aside, I think there is a concensus developing here.
The teamwork and attitude elements seem to be regarded as more important than the pure mechanics of getting the boat round the course.

Perhaps the driver does make the final calls on where the boat goes,but it is always more fun if you BOTH feel like it is a team effort.
This includes the little touches like covering for each others mistakes and not pointing them out.
Turning up in good time to help with the boat and not clearing off as soon as it is in it's space.
Retaining a reasonable level of concentration even when the race seems less than thrilling and the result looks like being dire.

Some of the most basic things are done differently by some helms and some crews. This doesn't mean there is a right or a wrong way, but it is a very good idea if you know what each other is expecting.

Tolerance and good humour go a long way in surviving and enjoying your sailing - this applies equally to helms and crews.

Is there another article coming on Crew's Heroic Saves - I can remember a few of those.

For those of you who remember Howard Stevenson; he will now only sail his 14 with one crew because he reckons he has got so slow and stuck in his ways that he needs his "Get out of Jail" card on a regular basis and there is only one person he trusts to do that!
#58
I'll be there with 3510 too.
Looking forward to it and to seeing Kevin's new boat.
Derek
#59
General National 12 chat / Re: Antony
27 Sep 2007, 03:27
Actually Stevie bought his boat from me.
Stig McDonald moulded it for me, Gerry decked it and did a fair bit of remedial work to rectify prosity and Stevie painted and fitted it out, but the concept was good.
The moulds went to Lynton after that (Murrell and Sue Pelling's boats as well as Bart) and subsequently to Mike Cooke.
The target was to get the basic hull out at under 3000.
Given the stiffness of the basic structure of modern boats, Carbon is simply not necessary.
Steve's boat is epoxy and mostly e-glass with some carbon tape in high load areas - perfectly adequate and no weight penalty. Carbon, being more rigid, is actually rather more brittle.
Buying the best you can buy because it removes one thing that might be making you slow is something we all are prey too!
#60
James,
I cannot answer that readily since the boat is in Exmouth and I am in Toulouse.
If you are building the boat around the plate, it is worth serious attention.
Since you have a boat and a plate, I expect you just want to see if it will go in and retract properly.
This time it is pprobably easier to check it with the mast in (to give you something to hold onto) and the boat rolled on it's side.
If this sounds too much trouble, check the pin to back of case and leading edge notch to plate tip - this should give you a decent idea though it might foul on the trailing edge at the back.
I would recommend you move the pin rather than butcher the plate to fit!
If you move the pin forwards, dont forget to check you've left enough space for the area of plate forward of the pin when retracted.
Position of CLR (centre of lateral resistance) is key to boat balance in conjunction with centre of effort of rig. You can move it without too much reduction in area by raking or over rotating the plate.
If you are going to do this, do mark the plate so you know the setting or you will end up chasing your tail with rake and plate position in search of balance. Mind you, for most of us this pales into insignificance relative to the fact that we seldom sail the thing upright anyway.
Good luck
Derek
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