Int Moth K3222 Project

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bornagainmothie
Posts: 222
Joined: Mon Apr 23, 2012 1:28 pm

Int Moth K3222 Project

Post by bornagainmothie »

Following an ad in our boats for sale section I have taken on the restoration of Int Moth K3222, a Stockholm Sprite design from the late 60s/ early 70s and according to photos from the archives, the boat that won the 1972 Nationals.

We started today, stripping the old paintwork back to bare wood to see what was underneath. Some of the paint on the bottom panels had peeled off anyway and wasn't too difficult to remove with heat gun and scraper. Julie had most of that scraped off before I got the rudder fittings and shroud plates unbolted :)

The side panels were not so easy. The original paint there was a much harder material and thinner layer, maybe a cellulose car paint?. Whatever it was had stuck well to the ply and had to be heated and scraped a square inch at a time. In all about 6 hrs work to get back to the wood all over. I avoided lifting the glass tape where it was bonded well , maybe look closer at all the joints later.

Discovered the sail number cut into the port side near the transom:

Needs a good sanding now to clean up, but leaving that for another day!

Lyndon
Attachments
looking better already
looking better already
3222
3222
starting the job
starting the job
bornagainmothie
Posts: 222
Joined: Mon Apr 23, 2012 1:28 pm

Re: Int Moth K3222 Project

Post by bornagainmothie »

More paint stripping this week, started on the decks. Some of the paint had peeled on its own, revealing a nice top veneer so i extended the patch to see what it was like further over. Not being a fan of painted decks I was really pleased to see that the ply is a striped mahogany and with careful treatment will be clean enough to varnish. There's no evidence of previous varnish though, it may well have been painted from new.
With rear deck back to bare wood and looking ok, I moved on to the front lower deck and up the side panels. It was easier to work on these by tilting the hull in a rope cradle suspended from the garage roof.
Cleaning up the bulkheads in the footwell exposed where there had been framework for small side tanks that have been removed at some time. Might consider building these back in to help stiffness.

Lyndon
Attachments
which half looks best?
which half looks best?
lower front deck stripped
lower front deck stripped
marks on bulkhead from side tanks
marks on bulkhead from side tanks
bornagainmothie
Posts: 222
Joined: Mon Apr 23, 2012 1:28 pm

Re: Int Moth K3222 Project

Post by bornagainmothie »

Not much work on the hull this week, been working on some new sail battens....
My Dad offered to cut a set of battens from a plank of Ash he had been saving for a worthy cause, how could i refuse?
The boat came with some plastic tube battens which did not encourage much shape in the sail. Batten pockets in this sail are 1.5" wide so current plastic/glassfibre battens look lost in them.
The longest one is 7ft reducing to 21" at the top. Dad cut the strips at 5mm thick for the longest and reducing to 2mm for the shortest, then tapered them roughly on the bench planer and evened the steps out by hand plane.
I took over to fit them to the sail which was on the mast layed out in the garden. Each one in and out many times shaving off a little more until we could get a nice aerofoil shape in the sail with the deepest curve about 1/3rd from the mast. Its difficult to judge without wind in the sail, but it looks ok now.

The other job was to modify the launching trolley to support the boat properly, and also make it fit my road base. The axle had to be narrowed by 3" which meant grinding the welds away on the stub axles, chopping the axle bar and re-welding the stub, then making a cradle and re-shaping the A frame to locate on the rollers of the road base. Would have been easier to start from scratch but there was enough tube to make exactly what I wanted, so it only cost a few cutting discs and welding rods. I now have a stable base to sit the hull in while work continues.
Attachments
Sail Battens
Sail Battens
bornagainmothie
Posts: 222
Joined: Mon Apr 23, 2012 1:28 pm

Re: Int Moth K3222 Project

Post by bornagainmothie »

More work on the hull,
strange things to investigate and lets make a new daggerboard case.
Attachments
fibreglass patches on deck
fibreglass patches on deck
jigsaw fun, wonder why?
jigsaw fun, wonder why?
below deck, not much support for the mast!
below deck, not much support for the mast!
bornagainmothie
Posts: 222
Joined: Mon Apr 23, 2012 1:28 pm

Re: Int Moth K3222 Project

Post by bornagainmothie »

I hadn't intended to go this far but....
some suspect repairs in the deck that need strengthening, no direct support under the mast step and I wasn't sure about the daggerboard case!
Case was originally lined with a lovely yellow formica but it was peeling off in places. The joint between case and bottom panels had plenty of resin but the front and rear spacers didn't look very well glued and could leak. Dribbles of resin in the slot difficult to remove. The slot was also much wider than the daggerboard so would be a very sloppy fit. All things considered, I gently warmed the seams around the deck ply and carefully split the joints without breaking the ply, it came off in one piece, so will be refitted once repaired underneath.

Amazed to see that a single piece of 1" wide spruce with fresh air beneath was all that supported the mast. Maybe that explains the jigsawed panel? I think all those compression forces from the mast need to be carried on a spine built up from the hog.
Attachments
Daggerboard slot from underneath. Not convinced its watertight
Daggerboard slot from underneath. Not convinced its watertight
insides of case, formica was peeling away.
insides of case, formica was peeling away.
case out, now rebuild can start
case out, now rebuild can start
solentgal
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Re: Int Moth K3222 Project

Post by solentgal »

This is good stuff......enjoying reading and looking at pics, :)
Sami.
bornagainmothie
Posts: 222
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Re: Int Moth K3222 Project

Post by bornagainmothie »

Thanks sami, it's nice to know you are following the saga!

I accidentally uploaded the case sides pic twice, here is the one i intended to show:

It might have been possible to re-line the case with new formica but an awkward job to keep it flat enough while glueing. I'm always suspicious of messy joints, they're usually a result of trying to stop leaks and in such a critical area, can only mean trouble later. As the Hunts Moth squadron will confirm!
Hoping the next installment can show something going back together

Lyndon
Attachments
Daggerboard slot from the outside.
Daggerboard slot from the outside.
bornagainmothie
Posts: 222
Joined: Mon Apr 23, 2012 1:28 pm

Re: Int Moth K3222 Project

Post by bornagainmothie »

Good news, new parts are glued in. I made a new central spine to support the deck and linked together with a new daggerboard case, also a pair of diagonal bulkheads to triangulate shroud points and mast step area. These should prevent the hull and deck flexing under rig loads without adding much weight.
A couple of ribs that were attached to the underside of the deck ply might be better built in to the hull, so I will add these before deck refitted.

A section of the bottom panel forward of the case had been repaired in the past but part of the outer ply was delaminated and covered in body filler to blend the joints. I cut out the whole section and replaced with some lighter ply. As it was originally butt jointed i retained the jointing strap inside and glued the new ply to it with epoxy.
Attachments
New daggerboard case and spine
New daggerboard case and spine
bottom panel cut out for repair
bottom panel cut out for repair
bornagainmothie
Posts: 222
Joined: Mon Apr 23, 2012 1:28 pm

Re: Int Moth K3222 Project

Post by bornagainmothie »

Long overdue an update. Conditions have not been suitable for curing resins in the garage recently, so its been difficult to move on much with the build. The hull fits neatly in the conservatory and its a lot warmer in there, but running the sander in the house would be a step too far! Messy stuff outside or in the garage, glueing in the house, has meant a lot of carrying the boat around, usually single handed. Lucky its a moth!

With the case and spine already in place, I fitted two deck beams to each side, before cleaning up and refitting the deck ready to be glued in place.
Moving on to the cockpit area, I decided to double up the thickness of the floor by adding some 3mm ply, bonded with epoxy to the original floor. Very flexible and only needed some weights and a few staples to hold it down. There were some strips of ply attached to the bulkheads low down which had been used to create framing when the bottom panels had been replaced many years ago. I removed these carefully so that my extra floor could be fitted neatly against the bulkheads and the joints remade with an epoxy fillet which will be much stronger anyway.
Following the marks on the bulkheads i cut some 3mm ply to reinstate the tank sides that had been removed long ago. These were pre-coated with SP and bonded in to some cedar strips in the corners.

The small side tank tops were made from some offcuts of old sapele ply that looks quite similar to the original deck ply. Its 4mm but very lightweight and should withstand some abuse from feet in the cockpit. Though small, the side tanks have stiffened the hull tremendously and will reduce the amount of water that can be trapped in the cockpit. A small elvstrom bailer should cope with minor mishaps!

Decks are all now glued in place and the edges taped as before with glass tape, but now epoxy resin instead of polyester. All edges of the tape are being sanded out as smoothly as possible, and will hopefully not be too visible under the varnish. The original decks have a good thick veneer which is responding well to sanding. Marks from the painted finish are coming out and darker blotches disappearing. Even the bulkheads are coming up clean. I hope to get some varnish on soon when its all evenly sanded, before rebuilding the gunwales.
Attachments
tank sides
tank sides
tank sides and framing
tank sides and framing
Decks on.
Decks on.
bornagainmothie
Posts: 222
Joined: Mon Apr 23, 2012 1:28 pm

Re: Int Moth K3222 Project

Post by bornagainmothie »

A couple of very thin coats of varnish on the decks. Makes all the paint stripping and sanding worthwhile as the colour in the veneer starts to show.
Attachments
Decks varnished
Decks varnished
Hotspur
Posts: 117
Joined: Sat Sep 10, 2011 7:38 pm

Re: Int Moth K3222 Project

Post by Hotspur »

Wow, what a difference! Was a lovely looking boat anyway, but that colour in the wood adds a great deal? Bet you can't wait to get it finished
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alan watson
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Re: Int Moth K3222 Project

Post by alan watson »

She's looking beautiful...but will we see her at Hunts Roadford or Banbury ?

Cheers
ALAN
Nessa
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Re: Int Moth K3222 Project

Post by Nessa »

Let's hope so!
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Rupert
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Re: Int Moth K3222 Project

Post by Rupert »

Looks stunning.
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bornagainmothie
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Re: Int Moth K3222 Project

Post by bornagainmothie »

Thanks for the comments, I'm really pleased with the new look, proud to be plywood!

Yes I'm aiming to have it ready for Hunts, still a lot to do. I will be there with the Mag7 anyway.

So, any ideas on a colur scheme for the outside? I was thinking of putting some paint on this one !!!

Lyndon
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