Stripping out the hull.....

[willothewisp123]

I own a National 12 3352 called Bounder. There are some photos of her on the boat list from when she went on Ebay.

I understand that she is the only one of her design....this is probably explained by the fact that she is the only N12 I have seen with large integral wooden bouyancy tanks. I would imagine this makes her well over the minimum weight - though it does make her comfortable to sail in light airs as they double up as seating.

I am only going to use her for club racing on handicap. Any thoughts on whether it is worth removing the built in wooden bouyancy tanks? They are completely hollow behind the wood with no internal bracing.

Thoughts would be appreciated

Thanks

Pete Hannon

[johnk]

The front bulkhead provides a lot of structural stiffness. Its replacement with an air bag will mean the bow floats lower after a capsize. I don't think you should remove this. The aft tanks will also provide stiffness. Weigh the hull first. Calculate the weight of the ply that would come out. Calculate the weight of replacement buoyancy. Is the net weight loss significant? I doubt it.

[Phil Brown]

Pete

I would say the buoyancy in the centreboard buoyancy tank was in exactly the right place

Being at the heavier end of the crew weight spectrum, I had been working out how to increase the buoyancy in Fantastic Mr Fox (a Design  8 ). My problem is that, having capsized, even with the crew in the water, the boat floats very low in the water with a shed load of water in it. This is a serious incentive in itself not to capsize  but also to shed some weight from the boat (Cost factor) and me (I'm trying!).

The main criteria is for buoyancy low down and as next winter's project, I was looking at putting in a c/b case buoyancy tank, very similar to Bounders, in carbon/foam sandwich of course. (Anyone else tried this ?)

What I hadn't yet worked out was how and where to lead the rig controls

Could you post or email me some photos of the side of the c/b case and the front end that would show the controls layout?

Thanks

[willothewisp123]

Thanks for the replies,

I hadn't considered the bouyancy aspect - only the weight saving.

I am a six footer and weigh in at about 16 stone - my crew (daughters aged 12 and 13) are slightly built fortunately, but all up weight will be high for the size of boat.

 I haven't capsized in her yet (too skillful or haven't been trying hard enough?  Only sailed her a few times as I got her towards the end of the season)  so don't know how high she floats - she might not be too bad with the volume in the side tanks. I think I had better leave it well alone.

Moving on slightly, I used to sail lasers as a teenager - and so utilised dry capsizing technique - can you do this in a 12 or do they flip too quickly?

Pete

PS I did have masses of photos of it fully rigged - as an aide memoire - I am doing some varnishing later in the week and will stick some pictures on of the rigging - and the rope layout - its got some "mad as a box of frogs" wires that run from the base of the mast on a muscle box, up the front of the mast just below boom level, then the wires run through pullies back down to the connectors at the front of the shroud sliders. This acts as a mast ram type device for straightening the bottom of the mast (I think). Never seen anything like it before - the joys of development classes!

[martin 1262]

It might be worth getting hold of the measuement certificte as thaat would inicate the weight when last measured. If it is not excessively over the min weight, you can make up any disavanatges in other ways, eg lightweight crew!

If you write to the N12 assocation you can get a new certificate for little cost!

For handicap racing, at the club, I woul not think it worthwhile, as mentioned before lost of stiffness etc, and also what will you find behind the tanks. Looking at the pictures it looks a pretty boat, and may not be so pretty with the tanks ripped out!

Hope that helps