Painting - First Undercoat

Today the wooden boat disappeared under the first coat of International Pre-Kote undercoat and is now white. I had to stop periodically to add a little thinners to the paint because the temperature was well over 30 degrees C and the paint wasn't flowing nicely. While paused I took this photo.

 

 

You can see the remaining brown epoxy coating on the plank above the newspaper. The two piebald planks above that show the remains of a coat of AquaCote that I put on over the epoxy but ran short of by one plank! AquaCote is a water based epoxy high build primer. It does all the right things, it's waterproof, dries hard, builds a thickish layer and sands easily. What it doesn't do is to flow out level so it holds brush marks or an orange peel effect if it is rolled on. Maybe I am not clever enough a painter to avoid these problems. I used it because I had it left over from a previous job and to fill the hollows in the epoxy coat under it. It did fill the hollows in the epoxy but it took me a day and a half to sand it back to a flat surface without grooves left by the brush. Never again!

 

Here is the other side completed. The International Pre-Kote flows out nice and level and will only need a gentle rub with some 180 or 240 grit paper before it gets a second coat.

 

 

The dog likes the concrete floor because it is relatively cool.

 

 

 

Ballast Tank Inlets

I have begun sanding the epoxy coating. First with coarse (80 grit) paper on the flat areas to remove the tops of the hills, bubbles caused by air coming out of the timber, dead insects, etc. Miraculously I didn't have any major runs to deal with. After the 80 grit I will change to 120 grit and go over the corners carefully so as not to remove all the epoxy. Then another pass over the whole hull with 120 grit.

While sanding the garboard plank (next to the keel) I sanded around the inlet to the water ballast tank and thought it might be worth a couple of photos. First  an explanation: the Able has two water ballast tanks in the bottom of the boat on either side of the centreboard case. Each tank holds about 45 litres of water providing about 90 Kg of ballast. The tanks are filled after the boat is launched through two holes in thebottom of the hull. As the water enters the air is pushed out through a vent pipe inside the hull. When the tanks are full the vent is closed so the water cannot run out of the tanks. When the boat is taken from the water on its trailer the vent is opened and the water runs out through the inlet holes. If the water ballast is not neededm boat already heavily loaded with crew and/or camping gear, the kept is kept closed preventing the water flowing in. Well that's the theory, I hope it works out!

Here is a photo from outside the boat. The result of the coarse sanding can be seen around the hole; the shiny areas are untouched.

 

The hole in the plywood plank is 32 mm daimeter with a small chamfer around the edge. The white tube is a plastic plumbing fitting with a 25 mm hole through it. To improve the glue bond to the plastic I put the fitting in my metal turning lathe and cut a shallow fine pitch screw thread on the outside. Then, after painting the edges of the ply around the hole with unthicked epoxy, the tube was screwed into the hole with plenty of thickened epoxy around it. After the epoxy set the tube was trimmed flush. The tube will protect and seal the edge grain of the hole in the ply.

 

On the inside of the hull, photo below, things are not so tidy! The back of the tube butts up against the inner part of the keel and the spaces either side of it will be filled with thicked epoxy to provide more support for the tube. The front of the tube will be cut away flush with the inside of the plank so that all the water can drain out. This will be done after the boat is turned over.



First Coat of Paint

It doesn't feel like 6 weeks since the last entry on this blog but the calendar doesn't lie. I have actually been sailing for half that time; two weeks in the Great Sandy Strait, two 2 day outings with the WBAQ guys at Caloundra and a day out at Wivenhoe. Another week spent catching up on chores at home. That leaves two weeks spent working on the boat.

I haven't put anything on the blog because sanding and filling is such a tedious process and is not very photogenic! However today I gave the whole outside of the hull two coats of epoxy to seal it. I started early in an attempt to avoid the worst of the heat and that helped but the epoxy was going off pretty quickly so I had to mix quite small batches. I used Boat Craft Pacific epoxy with the standard hardener mixed 2:1 with no thinners. This is sticky stuff to paint on, it is more a case of spreading it out thinly! The first coat took about 4 hours followed by a short break for a snack by which time ir was ready for the second coat, just slightly tacky to the touch. The second coat went on more easily because the epoxy flowed a bit better over the first coat. Another 3.5 hours and it was done.

Outside Of Hull Is Finished

Over the last few days the woodwork on the outside of the hull has been completed. Before I turn the boat over to work on the inside of the hull I am going to paint the outside. This will take quite a while because there is a lot to do before the painting starts. All the excess epoxy has to be cleaned off, all the sharp corners have to be rounded off, all the inside corners will have a fillet of thicked epoxy added and the whole has to be sanded and sanded and sanded!

With the sheer plank doublers in place, see the previous post, the rubbing strip and outer gunwale could be added. I did the rubbing strip first and made the mistake of putting the strips down the side of the hull first. This was a mistake because it made fitting the matching strip across the transom much harder as it had to fit exactly between the side strips. Not only that but it was curved and so had to be laminated in place. Here's the result (note that I am talking about the top strip without the clamps). There are three laminations, each had to be sprung into place  and then cut to length. Once fitted they were coated with glue and sprung back into position and then clamped. All very tricky and sticky!





 

Having made that mistake I added the strip to the transom to match the outer gunwale before the side pieces. I was able to apply more force to bend this one and made it in two laminations. Once the glue set I trimmed the ends of the strip flush with the sheer plank and put the outer gunwales in place. Here are some photos of the hull with all these pieces in place.

 

 

 

As I said, next job is to clean off the excess epoxy which is clearly visible in the photo above. Before I start on that though I am going to take my trailer sailer out for a couple of weeks sailing in the Great Sandy Strait. It will be sunny and hot but I am hoping for enough breeze to keep things reasonably cool and to keep the sand flies at bay!

Sheer Plank Doublers Fitted

Over the last few days I have fitted the doublers to the sheer plank, it took a bit longer because I had to do them one at a time and also went sailing for a couple of days. Here are a couple of photos of the doublers at the bow and transom showing how they fit. The joints all look a bit daggy at this stage as the excess epoxy still has to be cleaned off (I get most of it before it sets so what is visible is the remainder).

 

Here, at the transom, the doubling is carried across the top of the transom.

Last photo shows the bow of the boat with all the planking now finished.

Next job is to add the rubbing strip to the lower edge and the outer gunwale to the the top edge of the sheer plank. I know, it's confusing - the boat's upside down so lower and upper, port and starboard are reversed!

Planks 7 and 8 Fitted

After explaining in the last post that I didn't have enough clamps to glue 2 planks in a day I found that the last 2 planks don't need as many clamps. This is because there is almost no twist in the them so they more easily take up the required position. So, yesterday I added plank 7, one in the morning and one in the afternoon. Here is a photo of the boat with the 7th plank in position.

 

 

Today I made the pattern for the last plank, that's number 8. This turned out to be a pig of a job because there is no longer a piece of exposed mould to fix temporary supports to. Add to that the fact that my 17 foot long piece of ply wasn't quite wide enough and had to have extensions added at both ends (hot melt glue is magic stuff). Making the pattern and checking that it was correct took me almost 3 hours - it has been a 30 minute job for the previous planks.

 

With the pattern made and checked I marked out and cut the last 2 planks. Here is a photo of the boat with them glued in place, still clamped because the glue hasn't set enough to hold them yet. On a hot day like today, over 35 degrees in my shed, the glue goes off pretty quick but still takes 5 or 6 hours to set enough to hold the planks and there isn't any point taking chances!

 

 

This last plank is sometimes called the "whiskey plank" because it is a reason for a celebration. I'm celebrating with a gin and tonic, trying to replace some of the fluid I have lost today!

 

It isn't actually the last plank because the plans call for an optional doubling plank to be glued on top of it. this will add strength to the boat and I have decided that this is a good thing to do as it will help to stop the hull twisting and also help it withstand the inevitable bumps when it is moored alongside jetties or other boats. There are a few things to do before the 9th plank can be added so stay tuned.

Planks 5 and 6 fitted.

I'm back from my sailing adventure. It was a great trip, better than I ever imagined. I have been home for a couple of weeks but went sailing again for a week with the guys from the Wooden Boat Association. In the other week I have been hard at it in the boatshed.

First job was to scarf together more sheets of ply for the remaining planks. Since then I have been on a roll with the planking. I have settled into a routine where I am gluing one plank in place each day. The clamps come off that plank and are used to fit the second plank of that pair. While that second plank's glue is setting I prepare the pattern for the next pair of planks and use it to cut the planks. In this way I fit a pair of planks in 2 days. I tried doing a pair in one day (one in the morning and the other in the evening) but found the pace too hectic and I had to slow down!

Anyway, here is the boat with 5 planks fitted. A few clamps left after the majority moved over to the other side of the boat.

And, again, with six planks. The planking stock is on the bench at the right ready for the next pair of planks to be cut. As I write this, I have made the pattern and cut the 7th pair of planks ready for one to be glued in the morning. If I made another 40 clamps I could glue them both but I don't have enough scrap plywood for 40 clamps and, hey, the planking is almost done.

Gone Sailing!

There won't be any boatbuilding for a while because I am going sailing on a friend's Mottle 33. Here is a photo of the boat in her home marina (with the blue sail cover).

4th Pair of Planks

Added the second of the 4th pair of planks this morning. This means that half the planking is done! Here are some photos; first is the plank I glued on yesterday morning.

Next, this is the plank I glued this morning. There are about 40 of those plywood "hairpin and wedge" clamps, one every 100 to 125 mm.

A view from the aft quarter. It is hard to get a good picture from inside the shed. I need a bigger shed before the next boat!

And from in front. I don't understand the cause of the "haloes" except that the sun was shining towards the camera from my right.

3rd Pair of Planks and Bilge Runners

Since the last post I have been sailing for a couple of days. I took my Navigator (see link on left) to a Wooden Boat Association messabout at Caloundra - 2 glorious days of sunshine and wind!

More to the point here, I finished the outer parts of the keel. The doublers on either side of the centreboard case were glued in place. The capping strips to cover the edge of the ply were shaped and fitted into housings routed out of the outer keel and skeg. When the glued had set the bottom of the keel, from stem to transom, was cleaned up with hand planes. As I expected, this was hard work because it involved reaching out over the first 2 planks.

The 3rd pair of planks were test fitted, trimmed where needed and glued in place, one yesterday and the other today.

The bilge runners fit on the edge of the 3rd plank and have to be laminated in place to suit the curve of the hull. I worked out where to put them, covered the hull with plastic so they don't stick to it, glued them up (4 pieces 42 x 12 mm) and clamped them in place. Here is a photo:

After the glue has set I will remove the bilge runner, clean the glue off and taper the ends before gluing and screwing it permanently to the hull.

Behind the bilge runner is the cleaned up keel. Click on the photo to enlarge it and you can see the ply doublers along the centreboard case and the capping strips.

Roger, who is about to start on building and Able, asked how I had faired the centreboard case into the forward keel and skeg. Here are a couple of photos show this transition, first from above and second from the side.

The view from above. The ply doublers on the sides of the centreboard case extend over the skeg by about 150mm and are covered by a hardwood strip that is let into a rebate cut in the skeg. The end of the case log is covered by a short piece of the same hardwood. the doublers and the cover strip are tapered off to a blunt end that I will fill with an epoxy fillet.

Here is a closeup view from the side.

Outer Parts of Keel Fitted

I wanted to fit the outer parts of the keel or skeg while the centre of the boat is still easily accessible. Even with only two planks on it is a bit of a stretch to work on the centreboard case. There are two big pieces of timber involved and both have to be shaped to fit the curve of the hull. Here are photos of them fitted, glued and screwed in place.

Above is the forward section. It was shaped to suit the curve of the hull by trial and error and this was a slow process. The vertical piece of timber is wedged against the shed roof to hold things in place while I put the screws in from underneath. At the forward end (left of photo) the step is one half of the joint for the outer stem.

This is rear section or skeg. Same approach with the timber wedged against the roof. When shaping this piece to fit I made a template from scrap ply to fit the curve of the hull and then cut the timber using the template. This reduced the trial and error fitting of a big lump of timber and was much easier.

This last photo shows the butt joint between the skeg and centreboard case (both ends of the centreboard case have similar joints. There are 2 pieces of 12mm thick ply to be fitted either side of the centreboard case and I will extend these about 150mm past the butt joints to cover and reinforce the joint. The sides of the centreboard case are lower than the top of the skeg to allow a hardwood cover strip to be glued over the edges of the ply case sides and doublers. Once this cover strip is in place the whole length of the keel will be a continuous smooth line.

Second Pair of Planks

I had to glue the second pair of planks on in to stages, one plank yesterday and the other today. This is because I don't like putting screws through the planks at the stem, it makes holes that need to be filled when the screws are removed. So I use blocks with a V shaped notch and clamps - there are 2 in the bow photos below. There is a lot of twist in these planks and they are difficult to pull into place individually. Pulling them both in together, fitting the notched blocks and clamps would need 2 people. On the next planks I will try clamping "handles" to the edge of the plank and pulling them together with a Spanish windlass. If it works I'll post a photo.

There are a lot of homemade wooden clamps in use below, about 30! As I said in an earlier post, they work well and are cheap and can easily be modified to suit different situations.

Here is the stern end of the plank, not so much twist here and the end is held down on the transom with a couple of long screw clamps. These clamps are a bit precarious but provide enough pressure to hold the joint together - just don't bump them or they will fall off!

Here is yesterday's plank.

Before fitting the next planks I am going to shape the outer parts of the keel and fix them in place. This will be easier to do now while I can get closer to the centre of the boat.

First Pair of Planks

This afternoon I glued the garboard planks in place and am writing this with a celebratory beer in my hand! I knew I would have to do some final trimming of the bevel on the stem to get the planks to fit correctly. I didn't realise how much timber I would have to remove. I shaped the bevel using a long flexible batten. This worked OK for the batten but the 9mm thick planks didn't want to follow the same lines due to the considerable amount of twist they have to take. As the planking progresses the twist is less and my original bevel will be a better fit.

Here are a couple of photos of the planks and clamps in place. Screw clamps and glue blocks on the stem with wooden clamps and wedges along the keelson. These wooden clamps work well, easy to make from scrap ply and the wedges allow for a variable amount of pressure.

The glue running down the stem and across the planks at the transom is more than the normal squeezeout. I mixed up some unthickened epoxy and poured it in to gap between the two planks and around the centreboard case to try to make sure that any space left along the joint would be full of epoxy. Messy but I think it will work.

Starting the Planking Process

It's been two weeks since the last post and there isn't much obvious progress. However, I did go sailing for a week in my John Welsford Navigator and had a great time. I have also bevelled the transom, keelson and stem in readiness for the planks to go on - no pics of this as the changes are not obvious and photos of a big pile of wood shavings are not interesting. I bought the plywood for the planks, 9 sheets of marine grade 9mm Gaboon ply. Also 5 sheets of 4mm construction grade ply to make patterns for the planks. Interestingly, the 5 sheets of construction grade ply cost less than a single sheet of the 9mm marine ply!

The planks are over 5 metres long so I had to scarph joint the 2.4 metre sheets to get the necessary length. Here are some photos of the process. First, 4 sheets are arranged across the end of the bench in a staircase formation with each "tread" being 72mm wide. This provides an overlap in the joint of 8 times the thickness of the ply.

The steps are now planed away to create a continuous slope. As this progresses the glue lines in the ply give a good indication of how even the slope is. The planes need to be sharp and resharpened during the job but it is still hard work!

The sloping surfaces are painted with unthickened epoxy and left for 15 minutes or so to allow the epoxy to soak into the end grain of the ply. Thickened epoxy is applied to 2 of the 4 slopes and the joints positioned carefully so that the ply surfaces are level and the long edge is straight. I tack each pair of sheets together with a couple of staples to stop them slipping apart and then clamp the joints with 2 heavy cauls. One of the cauls is straight, the other has a slight crown on it (about 3mm higher in the middle) to counteract the tendency for the cauls to bend when clamped at the ends.

With one joint made the sheets are now almost 4.8 metres long and the scraphing process was repeated to add another 450mm to one end. The sheets are now 5.25 metres long and are filling the space in my shed quite effectively!.

While the scarph joints were setting I made a pattern for the first (garboard) plank using the cheap 4mm ply. This is pretty straightforward. I butt join the sheets of ply to get the length and then cut off a strip wider than the plank. This strip is then laid over the building frame and held in place with a few temporary nails. The edges of the plank are marked on the pattern strip from the moulds. The pattern is taken off and the marks are joined up using a long batten to get a fair curve through the points. Cut and trimmed to the line with a handplane the pattern is returned to the moulds and checked for fit.

Once the pattern is correct it is laid over 2 sheets of the marine ply a a line drawn around it. The planks are then cut with a jigsaw and cleaned up with a handplane. Here is the pair of finished planks.

The planks are laid on the moulds and held with clamps. Inevitably, some fine tuning is required but this can be done with a hand plane. Here are the planks at the bow of the boat. There is considerable twist required to get them into place and I'm doing this with shaped blocks and, while the glue dries, a few temporary screws will be used.

At the stern the planks will be easier to fix but some fine tuning is requireed here as well. The stripes on the edge of the transom are pieces of ply that I had to add to correct an error made while bevelling the transom. The bevel was perfect but I forgot to allow for the fact that the planks overlap and need the transom to be stepped to accomodate the overlap.

Last comment at this stage; this is my second glued lapstrake or clinker ply boat and the first pair of planks are the most difficult to fit. The process for the remaining planks is the same but they don't but together along the centreline of the boat and there isn't as much twist to deal with at the bow.

Three Joints

In the last week I have made and glued three joints. Doesn't sound much but two of them were quite tricky and one of those two was big! Starting with the one of middle difficulty, the joint between the transom and the keelson. First step was to make the triangular brace and screw and glue it to the transom. Once this was done the lower half of the keelson (it's in two 15  mm thick pieces) was glued to the brace and held with temporary screws.

 At the other end of the boat the first half of the keelson was glued and clamped to the inner stem. Once the epoxy in these two joints had set enough to hold the pieces together I applied glue to the two pieces of the keelson and put the second half in place with screws either end and clamps all along the length. Here's a photo of the stem end of things.

In the middle is the centreboard case which has to be glued into a slot cut in the keelson. The keelson is reinforced along this section by doublers to either side of it. These doubles are, like the keelson, laminated from two 15 mm thick strips. These were glued to gether and glued in place in one sticky operation, sticky for me that is. Epoxy everywhere!

Next step was to cut the slot in the keelson with a jig saw. This needed a bit of fine tuning with plane and chisel to get the case to fit. Once the slot was OK I opened out the sides about 2mm at the top to make it slightly funnel shaped, reason later.

With the board in place two plywood reinforcing pieces were glued either side to the case and to the keelson. These can be seen on the left of the photo either side of the mould. I mixed up a batch of stiff thickened epoxy and ran a small fillet around the underside of the joint between the keelson and centreboard case. This effectively sealed the bottom of the gap between the case and sides of the slot in the keelson. Once this thickened epoxy had begun to set I mixed more epoxy and poured it into the funnel shaped space from the top adding more as it settled until the joint was full.

While waitimg for all the above glue joints to set I sorted through the timber I had on hand for the masts and spars. These are all Oregon (Douglas Fir). I had toyed with the idea of making these hollow using the "birdsmouth" technique (Google "birdsmouth masts") but in the end I chickened out! They will all be solid, laminated from two strips of timber so that the opposing grain patterns resist and tendency for the wood to bend. Unfortunately I didn't have enough of the nice Oregon that I bought in a bundle from a deceased estate and will have to find a source of timber for the mizzen mast. I will work on the spars whenever there is spare time waiting while epoxy goes off.

I have built a rack against the outside of my boatbuilding shed (under an existing lean to roof) to store the spars and other timber.

Some Useful Machines

I was in the shed with the camera and it occured to me that some one might be interested in the wood working machines I use so I took some photos.

This is my new bandsaw, well new to me anyway (it was made about 20 years ago). It replaces my old bandsaw which was underpowered and would not cut timber more tha 25 mm thick. I haven't been able to stop this one yet! In the photo it had just arrived and I was setting it up and making a wheeled base for it prior to moving it into a space at teh back of the shed.

Boatbuilding needs timber that is finished to unusual sizes and often in long lengths. These can be ordered from a timber merchant (expensive and involves delays) or cut from larger planks as needed. I use the Triton workbench to rip the lengths about 3 mm oversize. The longer and sometimes heavy planks are supported on roller stands as the go over the saw bench. The planer in the background is moved to one side and the sawn timber is supported by pieces of pipe on the workbench. When the sawing is done the planer is moved to the saw bench and the sawn timber is run through it supported by the rollwer stands and workbench. This system seems to work well enough and saves money and time.

This is another "new" acquisition. It keep the shavings from the planer under control and helps with the floor cleaning - the floor is often covered in sawdust and shavings which is OK but if you drop something small it can be lost forever.

Last photo shows my Tormek grinder. This has greatly reduced the time I spend sharpening plane blades, chisels and knives. It is a magic piece of equipment. Previously I used oilstones and Japanese water stones but it took a long time to restore a edge that had been damaged by a nail or similar. I still use the water stones (kept in the bucket in the sink) to put the final edge on.

More on the Stems

I shaped the inner stem using the template mentioned in the previous post. When it was done I used the inner stem to laminate the outer stem. The outer stem laminations were 5.5 mm thick and would not bend around the curve of the inner stem. I put them to soak in cold water for about 3 hours and this made them pliable enough to take the curve. Here they are clamped to the inner stem sitting in the sunshine to aid the drying out process.

After several days to allow the laminations to dry out they were glued together with epoxy. Both sides of each of the 12 laminations (only one side of the outermost laminations) were coated with unthicked epoxy as a primer and then one side of each was coated with thickened epoxy to fill any voids in the joints. All 12 pieces are put together and clamped around the inner stem. There is plastic sheet to prevent the two stems sticking to each other. Here's a photo taken with clamps in place and after I had removed my rubber gloves and cleaned up a bit.

This next photo shows the two stems separated. Inner stem in front and outer behind with temporary braces to minimise springback.

Here is the inner stem in place in the building frame. There will be considerable sideways force on the inner stem as the planks are pulled into place hence the bracing. The white sheet sticking up between the back of the stem and the mould is plastic to keep the glue under control when the keelson is glued in place. The photo on the cupboard door provides inspiration as I work away at this long project, it shows John Sharpe's Able sailing (more photos of his boat at links on right).