National 12

General Boards => Boats => Topic started by: National 12 Webmaster on 16 Mar 2007, 12:04

Title: N1183 Tessa
Post by: National 12 Webmaster on 16 Mar 2007, 12:04
The life of N1183 Tessa. Design: Mark 2, designed by: Ian Proctor in 1952
Title: Re: N1183 Tessa
Post by: Tim Gatti on 23 Feb 2009, 11:51
Although the Mark 2 design was used to produce the first glued clinker National 12 hull (N1153 Wichcraft) for Robin Steavenson, there was some lengthy debate at the RYA, and uncertainty about the viability of the project, at the time.  Consequently, ribbed versions of the design continued to be built for some time after Wichcraft's completion. 
'Tessa' - built is 1953 and currently owned by Andrew Dawson, therefore marks the end of an era in N12 construction and was probably one of the last ribbed 12's to be built. (Attached photos are from a colour photocopy that Andrew sent to me recently)
Title: Re: N1183 Tessa
Post by: Tim Gatti on 23 Feb 2009, 11:51
And another...
Title: Re: N1183 Tessa
Post by: Tim Gatti on 23 Feb 2009, 12:08
I should have said that 'Witchcraft' N1153 was the first 'production' glued clinker N12 hull, as there were other experiments with this type of hull construction prior to 1952.  Robin Steavenson went on to win the Burton Cup in her in 1953.
Title: Re: N1183 Tessa
Post by: Tim Gatti on 07 May 2009, 01:27
Collected 'Tessa' from Andrew Dawson in Sheringham on Easter Sunday - thanks due to Howard and Sarah Chadwick for transport, Ann (Andrew's partner) for a lovely lunch, and to Polly - Sarah's dog, for an entertaining frolic on the beach!  She's in good condition but will need some work on the decks, planking and keel to get her ready for the Ribbed Boat Racing event on 31 May at Yeadon. 
Title: Re: N1183 Tessa
Post by: Tim Gatti on 07 May 2009, 01:31
Some more pics of ' before' - watch this space...
Title: Re: N1183 Tessa
Post by: Tim Gatti on 07 May 2009, 01:49
Jetwashed the interior (low pressure!) to remove all the gunk  and accumulated dust and dirt and washed out the skeletal remains of five tiny feet from in under the foredeck,.  Andrew had said they had found a rabbit's skull there when he picked up the boat from her original owner two years before. We think the 'Tessa' may have been used as a quiet retreat for the owner's cat to dine on it's latest catch. Ever seen a rat with five feet?  Mind you anything's possible in Essex.

The third plank on each side is suffering from  longitudinal cracks at the overlap between the rivets - but no sign of damage on the outside, so a good rake out and an infill of epoxy should sort it.  Decks are in a sorry state and the timbers have opened up a bit - particularly the fore and aft end of the keel, but nothing a bit of TLC won't put right.  Unfortunately, her original wooden mast is no more so she'll be rigged with a deck-stepped early metal Proctor spar complete with shrouds and diamonds - roughly in keeping with the period.  A galvanised plate and a surprisingly light, swept back, fixed rudder came with the boat and Andrew donated a wooden boom and an old suit of sails.  Let's go sailing!
Title: Re: N1183 Tessa
Post by: Tim Gatti on 11 May 2009, 11:21
Between the rain showers succeeded in removing most of the weathered varnish from the decks before getting Tessa into the workshop late on Fri night.  At least the worst of the mess was outside.
On close inspection found that most of the brass screw heads had corroded and softened the surrounding timber so set about dis-assembly and replacement.  200+ screws later and I had a Chippendale Mark 2 kit!
All fittings worth salvaging now getting their crud removed in a tub of white vinegar- see before pic of bronze shroud channel adjusters and drop-nose pins c1953. The rusty sheave blocks from the centre-plate system are destined for the scrap bin. 
Next job is to deal with some unsightly discolouration on the weathered decks that's too deep to sand out.
Title: Re: N1183 Tessa
Post by: Tim Gatti on 12 May 2009, 09:52
Got to work with some 40 and 60 grit on my half sheet sander and after an hour of very noisy sanding the decks are now looking much improved. Will finish them off with 120 tonight.  Vinegar bath worked its magic and brass work is now ready for a polish up.  The extent of the degradation of the varnish and timber around the screw-heads is something I've not come across before and after cleaning them up I'll probably seal them with clear epoxy before replacing the screws. Realised why both third planks show some cracking along the rivet line.  Planks were cut in pairs by splitting down the length of a thicker piece of timber so the planks on the port side are mirror images of those on starboard - presumably this helped to equalise the shrinkage and stresses exerted by the timber on each side of the hull.  The No 3 planks must have been prone to some later shrinkage on their top edges after they were rivetted in place.
Title: Re: N1183 Tessa
Post by: Tim Gatti on 13 May 2009, 03:32
Decking looking nearly new and all the screws have scrubbed up well - time to get the varnish brush and screwdriver out. Then it will be time to give the hull some tlc
Title: Re: N1183 Tessa
Post by: Tim Gatti on 14 May 2009, 10:56
Apart from the odd patch I'm pleased to say the decks have come up looking pretty good after two coats of low viscosity epoxy
Title: Re: N1183 Tessa
Post by: Tim Gatti on 18 May 2009, 03:16
Help! I'm running low on midnight oil and can't source a reliable supplier.  Gunwhales back on, thwart, knees and centreboard case capping re-instated after sundry repairs and half the hull and the transom stripped back to bare wood.  Haven't got time to weigh the scrapings.  Thanks to Brian Herring for bringing wires and bottlescrews for the diamonds and some suitable vintage tufnol jib tracks and fairleads to Ripon on Saturday.  Burton in 4 days time and Tessa needs to be ready for re-launch after full varnish and re-fit by the following weekend.  No pressure!
Title: Re: N1183 Tessa
Post by: Tim Gatti on 21 May 2009, 01:42
Hull stripped, repaired and sanded but not before my faithful Bosch palm sander gave up the ghost.  The first coat of Deks Olje went on last night.  What a nice clean, shiny bottom.
Title: Re: N1183 Tessa
Post by: Tim Gatti on 03 Jun 2009, 05:49
Got her all but finished but then had problems sorting her mast ,so she didn't get out of the workshop on Sunday. 
Will now take the time to put some self bailers in and add a couple more coats of Deks Olje to the hull which might help to plug some of the gaps in the planking, hopefully reducing slightly the need for the self bailers.
Hopefully she will be sailing at the next Ribbed 12 event on July 19th
Title: Re: N1183 Tessa
Post by: Tim Gatti on 03 Jun 2009, 05:50
And one more for good measure...
Title: Re: N1183 Tessa
Post by: Tim Gatti on 25 Jun 2009, 12:01
After many more hours in the workshop Tessa now has six coats of Deks Olje on her hull , neatly fitted mini Anderson self-bailers and secure straps and fixings to hold her buoyancy bags in place. 
Another mod I've found useful to do on the ribbies is to rake out the joint between the bottom edge of the centreboard case side and the keel and refill with a fillet of epoxy. Not an easy job as the joint is inside the centreboard slot about 45mm up from the keel band. With a steel plate, the slot itself is only about 20mm wide so there's not a lot of room for manoeuvre.  I've made a couple of small, cranked, raking out tools from an old ss wall tie and use a syringe with a fine tube attached to lay the thickened epoxy fillet into place along the length of the slot joint, then tipping the boat onto the opposite gunn'l the next day to do the joint on the other side.  It's a fiddly job but has a dramatic effect on reducing leakage, so it's well worth the effort.  You can see with the mention of Andersons and epoxy that I'm a firm believer in mixing the old with the new.
I'm just sorting the rigging and fittings on a very old Proctor mast of 1950's era which has both diamonds on fixed spreaders and shrouds and then Tessa will be ready for her re-launch in time for the next Ribby Event at Yeadon on 19 July
Title: Re: N1183 Tessa
Post by: Tim Gatti on 25 Jun 2009, 12:11
A couple more photos
Title: Re: N1183 Tessa
Post by: Tim Gatti on 06 Jul 2009, 07:24
Tessa was relaunched at Yeadon Tarn on July 1st with a distinct absence of fanfares, bunting and champagne but plenty of interested passers-by.  She handled well in a near non-existent breeze and, as anticipated, leaked a little due to her being out of the water for at least the last 30-40 years.  She's wearing a modern suit of sails in the pics attached and is now ready to join the fray on 19th July when five ribbies will take to the water for another round of close racing. I'm hoping a good dosing with a hosepipe and a thick layer of wet newspaper inside her hull to retain the moisture for a few days before her next outing, will help her planks to swell!
Title: Re: N1183 Tessa
Post by: Tim Gatti on 28 Aug 2009, 11:51
'Tessa' under sail at the Ribby Sailing event at Yeadon Tarn July 19th '09, with Ian and Margaret Purkis in charge.
Photo by Jennie Clark