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Transom Flap fitted to vintage 12 2268

Started by Jon Rawson, 07 Dec 2013, 01:48

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Jon Rawson

Please can anyone with knowledge of vintage 12's kindly asist me with some advice over the transom of 2268? I intend to bring her back to something approaching her former glory to sail in CVRDA events and I hope some of the class association's too in due course.
There is a little information about my boat, called Hi-Fi, on the site and a picture of unknown age. She is believed to be a 'Clean Sweep' design from about 1965, clinker ply construction. The last owner obviously looked after her well and overall she is pretty solid although requiring a complete strip and repaint and general repairs. The main problem area is the transom. Around the lower rudder fitting it has been split by the screws and rot has set in so a new section will need to be grafted in.
2268 is fitted with ply 'quarter' buoyancy tanks at the stern with thin plywood panels in the transom on the outside of the tanks. Internally this leaves only a narrow section of the transom exposed near the rudder. Here is fitted an inward opening transom flap that is 10.5 cm tall. Current flap is ply, sealed with rubber and held in place with elastic. I am unsure whether this would be more trouble than it is worth and whether I would be better off doing away with it when repairs are made. Please does anyone know whether this inward opening flap would have been an original fitting? I have no wish to alter an historic boat but the blessed things can be problematic enough when they open outwards. If it is unlikly to be original it can go and I will carry an extra bucket. 
Thanks.

Chadders

Hi Jon  Transom flaps must open outwards to work properly and are normally made of clear 5/6mm perspex with a hinge down the inboard edge or very thin bendy clear material that will bend when the water pressure comes on from inside. Hold them shut with some shock cord fixed through a hole in the middle of each flap and onto a clip on the hog for easy release or up to a cleat on the back of the plate case on some cord so you can see and reach the release point more easily.  They may have been fitted as you describe from the start but it is not the normal way of doing it.  Come along to the Dinghy Show in early March, lots of enthusiasts on our stand to explain anything you may need and probably lots that you didnt know you needed too.  We use clear material so you can see the wake and make sure the transom is clear and dont worry about sealing as they should be well above the waterline as long as you are sitting in the correct place.  Very useful things to have rather than bucket and chuck it.  My own flaps are the very thin type held on by the rudder fittings so no extra screw holes needed on Triarda N2266 and on Hoodoo N2683 they are 6mm with hinges but both work equally well.   Hope that helps.  Howard C

Jon Rawson

Hi Howard, Thanks for the reply. I appreciate that properly working flaps are useful but of course the problem I have is that I can not fit an outward opening flap because the rudder stock is directly behind the narrow section of transom available as the rest is covered internally by the built in buoyancy tanks. The clearance betwen transom and rudder stock would render an outward opening flap useless. I have never encountered an inward opening single flap before which is why I was wondering if it was a 'good idea' fitted by a previous owner and not original spec. The rear quarter tanks look original and I am reluctant to do away with these and revert to buoyancy bags. I can not see any pictures on the class site of another 12 with a single centre flap, they are all conventionaly positioned twin flaps or absent on pre '65 'ish boats. I would guess that there are not many Clean Sweep 12's left and I would rather live with a dodgy inward opening flap (peg it shut and elastic to open I suppose) than alter an original boat as the whole idea is to have a classic boat to sail. But if it was not original it can go. I will certainly visit the 12 stand at the Dinghy Show. Regards, Jon

paul turner

Hi Jon.

Just to add to Chadders advice (which I totally agree with if you actually want opening transom flaps!) but I am seriously considering fixing the transom flaps on my China Doll N2487 as they are so rarely used in earnest and you always get water coming in when you put the rudder on. It's useful to see the wake for the trim of the boat, but having fixed transom flaps (ie windows at the back!) has not been a problem with Starfish N2020. Indeed neither the original China Doll N2403 nor Whisper N2492 have transom flaps having full rear tanks and they went fast enough!

In other words I'm saying "forget opening flpas, just have fixed windows and keep your feet dry!" 8)

This may generate some debate!

Paul - N1650, N2020, N2399, N2403, N2487, N2492, N2750, N3157

Jon Rawson

Hi Paul,
Many thanks for your observations which are much appreciated. I have posed the same query on the CVRDA boat repair forum along with some photos and it was pointed out that I may be able to get a side hung outwards opening flap behind the rudder stock. There would be about 3 cm clearance which would allow the flap to open slightly more and a bit extra when the rudder is turned. That would allow some draining. I have to say that I am tempted by this or as you say just living without a flap. Regards, Jon

angus

It is important to have a transom flap that opens and closes as an important function of a transom flap is to stop the water rushing back in when you get it a bit wrong. I have twice tried doing away with the flappy bit with boats with rear tanks and with both boats I found it very difficult to get rid of water in anything other than ideal conditions so I doubt if your inward opening flap would work.
With out seeing a picture I can not see why a sinngle piece flexible flap would not work unless the opening is so small as to be of little use anyway.
 
All smoke and Mirrors. N2153, 2969, 3411

Martin (Guest)

Jon...seen the photos you are referring to...very unconventional set up. it seems to be that originally it had 2 large Transom flaps which now seem to be covered with poorly matching wood. The rear tanks look to me to be retro fitted, and do nothing to help the situation in getting rid of water in a hurry. Look at 2306 on before and after..i did this restoration a few years back and whilst this was a more conventional rear tank set up I removed the tank because they tend to leak and fitted bags. The transom flaps did the job needed As did the bags.
i would be inclined to remove the transom altogether and replace with something a) more useful and b) prettier to look at. If you think it's a project too far I am sure there are some boat repairs that would take that on for hopefully not too much £££. 
As an alternative which might be cheaper why not remove the tanks  and the wood infill?  Then get some large Perspex to fill in the void. Looking at it it seems larger than average but one things for sure it will empty you boat of water in double quick time!! Might be worth trying that first, and make some repairs to the bottom of the transom! 
I would leave the foredeck alone does not seem much wrong with that..but not sure what the cross member is there for..it may be keeping it all together!!! 
 
Hope that helps