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Messages - Nev

#1
A pdf file showing conventional 'water lines', 'cross sections' and 'buttocks' added to the Dropbox design folder.
Nev
#2
A few people have expressed an interest but nothing particularly serious; however it's early days.

My previous experience is with wood and it shows in the design.
However I am happy to collaborate and modify the design to suit anyone who has a serious interest.
 
Cheers Nev
 
PS a recent advert on ebay offered 10 sheets of 4mm marine ply for £65 and many offers for cedar planks which would provide material for the strip planking.
#3
This N12 design is the culmination of many months of effort. The design aim was to produce a boat that (i) followed the latest N12 concepts (ii) was dimensionally very accurate and was (iii) easy to home build in wood with only reasonable levels of skill.

If you are even slightly interested read the article at N12 Insidious (this is a link to a 'Dropbox' file - simply close any 'sign in' or 'create an account' window to access the file). The article gives further links to all the design documents required to build this up to date N12 at home.
 
With a little more work and an injection of suitable expertise it is quite possible that all the parts of the design (or a similar design) could be cut out using CNC machines. Not quite a 'flat pack' N12 but going in that direction.

If there are any queries or questions please email me ( nevgreen@gmail.com ).
#5
Stuart
Attached are some sketches.
Cheers
Nev
#6
Stuart
Have you looked at the Discussion 'T Foil Rudder with Tilt in Stock - Concept Design'.
It seems to have most of the features you are looking for but is 'tilt in the stock'.
Cheers
Nev
#7
Revised attachment.
Pivot pin diameter increased to 10mm, pivot on the stock increased to 10mm thickness and the profile of the rudder blade changed.
#8
As drawn the pin (about which the foil rotates) is 8mm dia and the pintle pivot on the stock formed from 6mm thick aluminium plate and welded to the stock. As you say it is a concept and all of the dimensions can be adjusted.

My main concern is that the blade area moves relative to the pintle as the foil angle is adjusted, and that is not the case with the more conventional arrangement of tilting the pintle and the blade together. Hope that makes sense.
There is bound to be an effect on the weight/feel of the rudder as the foil angle is adjusted. As the foil angle moves in the positive direction the blade area moves forward relative to the pintle. That will probably make the rudder feel lighter and vica versa. This aspect may or may not be acceptable. Someone may already have tried this approach and will know if it is workable or not.
Nev
#9
The attached file shows a concept design for a T foil rudder with tilt in the stock.
It should be easy to retrofit to an existing boat and relatively easy to DIY build.
Comments welcome.
Nev
#10
Boats / Re: N3352 Betty Bounder
07 Dec 2014, 09:58
Nice to see Bounder looking so good.
Bounder was designed to carry weight without significantly increasing wetted surface area.
This was achieved but had a negative effect on marginal planing and perhaps a good effect on light weather performance.
The tanks added to the weight but not significantly and contributed to an attractive boat that is very comfortable to sail.

If anyone is interested I have been working on a new N12 design which has a double bottom and is suitable for home building in wood.
The concept is to buid 'inside out'. That is start with the floor, case and bulkheads and lastly fit the skin. The benifit is a simple build jig and an almost complete rigid boat as it is seperated from the jig.
The design process uses Google Sketchup which is a free 3D modelling package. I have a document which describes the process for designing a N12. If you are interested in designing your own 12 send me an email ([mail=nevgreen@gmail.com]nevgreen@gmail.com[/mail]).
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