Monday, December 22, 2008

A Momentus Occasion

No not the launch, not quite.

I finally got some paint on the hull.  The sanding of the first load of exterior bog was completed last week, and the second fill on the underside was hard enough to sand at the weekend.  I made a start, but was otherwise engaged and so am now a little more behind.

Sunday was spent fixing a couple of things on the Land Rover to get it through the 6-monthly Warrant of Fitness certification that is required in New Zealand.  The relatively straight forward job of changing the power steering belt became an epic due to seized bolts.  The other job I knew had pitfalls associated with it.  I learnt so much in the process of completing the drop arm ball joint fix that I posted my findings here in the hope of my experience being useful to others tackling the same task. 

Anyway, last night I finished sanding the second fill and then I started preparing to paint.  I washed the bottom down with a warm solution of liquid sugar soap to degrease, remove the dust and any amine blush (a waxy emission from cured epoxy), then rinsed with plenty of water and allowed the boat to dry.

I then applied a coat of Taubmans UnderProof Acrylic Primer Undercoat.  This is a water-based acrylic with what smells like an amount of latex added to prevent bleeding through to the top coat.  I'm going to be using Taubmans Living Proof Indoor/Outdoor Acrylic Enamel Gloss as the top coat.  The reasons to use house paint rather than marine enamel like I tried for the cockpit interior are twofold.  Firstly, the marine enamel requires 24 hours between coats, whereas the acrylic enamel requires only an hour or two.  Secondly, the smell of the marine enamel was awful, even with the garage door closed it could be detected on walking passed while the boat dried inside.

Obviously there is a Christmas break coming, and we are off on a family camping trip until after New Year's, so the launch will definitely be in 2009.  I'm also pretty certain it will be in January of that year.

Wednesday, December 10, 2008

No Longer Without a Paddlle

At the weekend I finally plucked up the courage to cut the flats on the end of the paddle loom.  The profiles don't match exactly and one is cut a little too deep where the ply blade is supposed to come up flush to the loom, but its too late now as the parts are stuck together with waterproof polyurethane builder's glue and its all cleaned up ready for varnish.  Its not the thing of beauty I had in my mind's eye, but should be good enough to ensure forward motion is maintained.  Lets call it the paddle Mk I.

Last night I finished the main fairing compound application to the hull.  I'm now out of epoxy pretty much and have developed a loathing for mixing thick fairing compound; it takes longer to mix than it does to spread over the boat.

So I can spend a couple of short evenings painting the seat and vanishing the paddle.  Then, at the weekend, its out with the power sander and I can turn all that laboriously mixed and applied fairing compound into dust.

Thursday, December 4, 2008

Meanwhile, in the Garden...

Here's a little mini-project that I did on Sunday while a load of epoxy was curing on the boat.

We had a few sunflower seedlings that needed to be planted up, but really had nowhere in the garden prepared for them, so they had to go in pots.

We also have a good number of strange, octagonal, terracotta pipes in the basement, 400mm long with a 100mm diameter circular bore.

I closed of the bottom end with a disk of tanalised timber, nailed through 4 holes drilled around the bottom end of each pipe.  I added 10 metres of thick sisal rope and 10 metres of thinner sisal cord and this is what I came up with.  

Sorry for the fuzzy image, it was pitch black on the viewfinder and a bit too dark for the autofocus it would seem.

Coaming Lip

Although I don't have a spray deck, or know how to Eskimo roll, I want to include a lip on the cockpit coaming to hold a spray deck in due course.  If I'm to try and cross the Rangitoto Channel in this home built contraption, then I really don't want to get swamped half way across.

To this end, I made a crown of pins all around the coaming and balances a length of 8mm knitted synthetic rope on this, with the odd extra pin tensioning the rope.  The rope had first been dipped in straight epoxy resin to soak it.



The pins are now removed and I've started the lengthy process of smoothing (or fairing) the outside of the hull in preparation for painting.  There is nothing to add to the kayak now really, just filler and paint.  I need to paint the seat and find some closed cell foam to pad it, and I still haven't got round to making a paddle yet.

Thursday, November 27, 2008

Cockpit Coaming

So after the deck went on the last real job of building was to cut out the cockpit hole and line it with a coaming strip.  I wasn't looking forward to this part too much because while it is woodwork, its not the orthogonal, easy-to-measure joinery that I'm more accustomed to.

I made a template for the hole by turning one of the plan sheets over and on the plain back marking the centre line, deck beam positions and the run of the cockpit stringers.  I joined the tapering lines of the stringers with the curve of the dustbin lid at the aft end, and to an upturned bucket at the forward end.  I transferred the curves to the kayak by punching through the paper with an awl.  A little adjustment by eye was required to get a more pleasing line on the forward end before the line was followed by the jigsaw.

On the same day I prepared some pieces of ply, 120mm wide and 700mm long, cut across the outer grains of the ply (the way it bends easiest).  I laid these pieces on the driveway with an old towel over the top and soaked them with boiling water.  A few minutes later I filled the bucket that had acted as a template with sand and the wrapped the pieces (all stacked together) round the bucket and held them in place with a ratchet strap.

Two days later the ply was mostly dry and so I started to lay the curved pieces up on the kayak.  I was originally going to make the coaming out of two thicknesses of the 4mm ply on end, wrapped aroung the inside edge of the cockpit cutout.  This looked a little clunky though, so after mulling it over for a couple of days, I abandoned the inner layer.

So tonight I trimmed up the pieces with a jigsaw.  I marked line parallel to the deck with an offset block then partially flattened out the curved end pieces to trim them.  The straight side pieces were then trimmed to fit between the ends from ply with the outer grain running length ways.  For the bottom edge, I marked the back of the coaming where it was level with the bottm edge of the cockpit stringers down the sides, and with the bottom of the deck beams on the fore and aft centre line.  I faired a curve between the straight sides and the mid point and then cut it out hoping it would look OK when curved back on the boat.  This shape has meant the a very deep section to the coaming at the aft edge, which was the intention since there is no real provision for a separate back rest in this kayak.

After a dry fit test I mixed up the epoxy, pre-wet each joint surface and primed out any parts that would be no longer accessible.  I then added plenty of microfibres and used this to bong in the coaming.  I held everything in place with temporary screws, and on the end joints between the side and end pieces I used broad packers (covered in plastic parcel tape) under the screw to cover the edge and keep the faces flush.  The leftover epoxy and any squeeze out was then stuffed back into the gap between the deck and coaming to form a small fillet and improve the bond.  Its definitely warming up here now and for the first time I noticed the pot of epoxy getting really hot in my hand as the curing reaction started to happen.

To finish the coaming of I will trim the edges into a fair curve and fit a lip the the upper, outer edge to take a spray skirt.  I was going to use some steamed pine for this, but I think the curves are too severe to even bother trying.  Instead I'll soak some 10mm rope in epoxy and pin it in place, then fair it in with filler while fairing the rest of the outer hull.  And that's really all that is left to do.  Tape the deck seam, fair it in along with the other external tapes and then sand and sand and sand, and then paint.

Oh, and there's also the small matter of making a paddle...

Friday, November 21, 2008

Fully Decked

Progress has been slow, its been hard to grab much time in the last week or so. 

I have managed to get the deck on the kayak though.  I did this through last week, and at the weekend I planed of the excess around the edges and sanded any epoxy that squeezed out of the joint.


On Wednesday I managed to get into the garage for a brief moment to fit the PVC pipe ends that I'm using for hatches.  I stuck 3  small, curved face blocks around the underside of each of the holes to increase the gluing surface and held these in place with a small screw each.  I then added plenty of epoxy with microfibres to the glass tape the I had previously bonded to the tubes with PVC cement.  The fit in the holes was tight enough not to require any tape, pins or clamps.  I'll remove the temporary screws, clean up the excess resin and fillet and fill the deck/hatch transition when I'm ready to tape the deck/hull seam.


Finally, here's a shot of the copper pipe that I inserted in the bow to hold the toggle rope.

Monday, November 10, 2008

Improvisation

For me, part of the fun in making my own stuff is in finding alternative uses for everyday items, or alternatively, finding an everyday item to use out of context as a cheaper alternative for the 'proper' part.

The toggle eye I mounted into the bow of the kayak serves two purposes. Firstly, it must reinforce the hull and prevent the pull on the toggle rope from deforming the hull or pulling loose. Secondly, it must separate the hole through the hull from the airtight chamber formed ahead of the forward bulkhead. For this purpose, I employed a short length of 15mm copper pipe. I carefully marked the angles after boring a hole with a 16mm spade bit and cut the ends with a regular hacksaw. I scuffed the surface with 60 grit paper to allow the epoxy to key into the copper. The pipe is encased in a large block of epoxy/microfibre blend, which once cured, I filed back the ends about 1mm each side to be flush with the hull.

Kayak hatch covers are available from lots of outdoor, marine and specialist kayak shops, but the cost in the region of $100 upwards each. I don't need to use the airtight compartments ans storage, I just want to make sure they are dry, and if not (epoxy isn't totally waterproof, although it does take lengthy immersion to get any noticeable absorption) I need to be able to sponge out and air the compartments. To this end, I purchased a couple of 90mm storm water pipe covers. The consist of a short length of 90mm PVC pipe (about 70mm long) with one end open and the other covered by a removable, threaded cap. Again, epoxy wont bond to PVC and I didn't want to rely on simply scuffing the surface of such a large join. I think I read of the vague details of this process, but I made up the details myself.

Firstly I cut a length of glass tape just long enough to wrap round the pipe. I then cut it length ways down the centre. I laid 2 long strips of masking tape, sticky side up, on the workbench and stuck a half-width of glass tape to each, keeping the edges as straight as possible. I then piped a generous line of PVC solvent down the centre of each piece of glass tape. This was then wrapped around a piece of pipe, keeping the 'good' edge of the glass tape parallel with and just below the bottom of the threaded section. The masking tape keeps the glass in contact wit the PVC and allows pressure to be applied so that the solvent is partly absorbed in the glass weave. When I come to mount the pipes in the deck, I'll then add epoxy to the glass tape which will get a good bond with the part of the glass that is not already embedded in the PVC cement. The pipe and caps are grey, but I'll spray the caps with black enamel and any pipe showing above deck will be faired in with an epoxy fillet, primed and painted the same colour as the rest of the boat.

Catchup

I seem to be falling behind with the blog entries. I think the main reason is that I want photos to help describe a process or an idea, but either don't take them (because I forget or the process is too messy to involve an expensive digital camera) or because I get a bit fed up with the whole download - crop - resize - rename - upload process involved in posting them.

So here's a text only catchup...

On Wednesday I managed to screw the remaining forward portion of deck in place and I removed the still-damp towel to let the wood dry whilst in its new curve.

On Thursday and Friday I was too tired and did nothing - sometimes you just need a break.

On Saturday I only had a couple of hours, so I marked out the position just ahead of the forward bulkhead where I wanted to mount an inspection hatch and then I unscrewed the deck. This took a while. I then trimmed the deck up to within half a carpenter's pencil width of the hull with a new neat cutting jigsaw blade. I then swapped to the thin curve-cut blade and cut out the inspection hatch hole. I also prepared a piece to become an eye for the bow toggle - more of this later.

On Sunday I epoxied in the toggle eye and primed out the underside of the deck with plain epoxy. This was a hassle because it was very windy and all sorts of dust and leaves blew into the garage entrance and stuck the the tacky deck. Also, the wet of the resin caused the deck to try and curve back in the opposite direction of what was required. I quickly mixed up some epoxy and microfibre blend which I applied to the inwales, cockpit stringers , forward deck beam and forward bulkhead. Then it was on with the deck and in with all those screws again. Earlier my son Samuel had helped me take all the screws out of the scrap pads, put shiny brown parcel tape on one side of the pads and then put all the screws back in again so screwing down the deck could be achieved whilst the epoxy was still workable.

Tuesday, November 4, 2008

Torture Chamber

The main method of construction on the kayak up to this point has been stitch and tape. Pieces of plywood have been cut to shape and stitched together along there edges with cable ties before a permanent fixing of glass fibre tape and epoxy resin was applied. Another related method is called tortured ply, where compound curves are forced into the plywood. Its relatively easy to get a sheet of ply to bend in one direction at a time, so boats designed for this method of construction have panels shaped as sections of cones or cylinders. But the deck on the kayak is convex across the beam but has a concave sheer, the profile of the top edge of the side panels.

Last night I started putting on the deck on the forward end of the kayak. I screwed an oversize sheet in place at the halfway length of the cockpit. this allowed be to strap the middle section of the sheet roughly and draw an outline to trim the sheet to - still oversize but now by 30-50mm all round.



More screws were placed along the inwales working from the midships forward, and the stresses on the screws got greater as the curve was formed. I used scrap ply packers under each screw to prevent the deck springing back and popping all the screws through. As I approached the forward bulkhead the gap between the inwale and the deck was getting bigger and something needed to be done. I persevered for a while with a couple of ratchet straps holding things down, but it wasn't going to work.



At this point I took of the ratchet straps and then rearranged 3 straps over the top of an old towel that was soaked in hot water. The idea is that the warm and wet environment softens the fibres of the ply and makes it more agreeable to the compound curves being forced upon it. Wooden packers over the inwales concentrated the ratchet straps' force in the right direction while rags protected the deck and hull from the heavy metal hooks and ratchets. While tightening all this lot up, holding the ply with one hand and most of my body and tensioning a strap with the other hand, there was a pinging noise and a sharp pain in my shoulder. The torture victim had fought back.



I don't know what the outcome of all this was, I dared not look in the garage this morning so I'll conduct the post mortem tonight.

Thursday, October 30, 2008

How to find time...

Its taking a little longer than expected to build this kayak. Partly this is because I have to squeeze time in between other commitments, especially family, and partly because I'm learning how to do so many of the tasks involved.

When I get around to the 2-man version that is to follow, I think I'll be quite a bit faster. Although there are significant differences in the design and construction, many of the basic processes are shared, and I'll now be able to tackle those with the kind of confidence that only comes from experience. I'd like to think I won't make so many mistakes; for example I know now to be tidy when using the epoxy to avoid hours spent scraping and sanding to clean up the mess. It will also be down to less procrastination. Over-thinking a practical problem, such as how to shape a piece or attach it, is a time wasting exercise. Some of the parts I've worried most over have actually been very easy, and its amazing how often the solution springs to mind just for being in the workshop, tools in hand.

But I will still need to spend some time making it, and where will that come from. Well apparently the average UK adult spends 24 hours per week in front of the television. That's 1/7th of their life! Its not much better in New Zealand, where the average is 20 hours per week (but then programming is nowhere near as good). The other day I slipped into an old habit and picked up the TV guide. It was October 28th and the guide was still folded back on the pages for October 2nd. It's not that I've not watched any TV, but not much. I no longer browse the channels looking for entertainment, I just sit down to watch the three of four shows a week that I actually want to watch. I think 20 hours of TV per month is far healthier than 20 hours per week. And once I've got a kayak to paddle it'll be healthier still.

Paint!

Today I decided I was done with the filling/sanding cycle on the interior. I washed down the cockpit with warm soapy water and tidied the garage while the kayak dried in the sun. After dinner I went back to the garage and applied the first coat of one-part marine primer. I was expecting all sorts of blemishes to appear once the colour was evened out, but I'm actually pleasantly surprised how smooth it all looks.

There won't be much progress now until the 2 coats of primer/undercoat and 2 coats of top coat are on, unless I do a bit to the paddles. I've shut up shop for tonight, but at some point over the weekend I'll post details of the paints I'm using and where exactly I got them from. It looks like the primer will be enough to do the outside as well, but I need to get hold of some different top coat; bright orange me thinks...

Monday, October 27, 2008

Tow Point Reinforcement

Here's the tow point reinforcing with the bracing still on while the epoxy cures. The brace is a strip of wood running along from the centre of the deck beam to the centre of the aft bulkhead to ensure the top of the reinforcement stays at the level of the underside of the deck. The main piece is screwed to the brace and the 'knee' is taped to both to stop it sliding during the cure.


And this is it without the tape and bracing. The top needs a little cleaning where some epoxy that squeezed out of the joint ended up along the sides of the brace. I covered the brace with brown, plastic parcel tape to prevent any bonding between the temporary brace and the permanent reinforcement. This part isn't in the design, but I'm keen that the kayaks should be able to two one-another, and background reading suggests that a tow point is best mounted immediately behind the cockpit.


Finally, all the sanding of the cockpit is taking its toll on the rest of the garage contents. I'll try to do the exterior sanding outside I think, otherwise the camping gear may get wrecked.

Sunday, October 26, 2008

Last Cockpit Details

Today's a public holiday, Labour Day. I've been spreading myself pretty thin between family, household chores and making progress on the kayak. However, I got the second fill sanded back and added the final details to the cockpit before painting.

The first fill used nine pump's worth of epoxy, the second fill used three, and the last fill applied today used only one and there was heaps left over. I know the finish still won't be perfect, but its as good as I'm prepared to do for the inside of a closed cockpit kayak. It should take less than half-an-hour to sand out tomorrow, so I can wash down and get some primer on.

I also primed the seat panel on one side with plain epoxy. I popped the washers out and sanded them with some 240 grit and then forced them back into the recessed holes with the resin in the hope that they bond in place.

I also cut and bonded in the cockpit stringers, as well as priming them on three faces, leaving the top bare ready to bond to the deck. Behind the aft deck beam I added a couple of blocks, one cut to a curve to fit snugly under the deck, the other a small knee style brace between it and the deck beam. The purpose of these pieces is to reinforce the area immediately behind the cockpit so I can bolt an eye through there to mount a tow line.

Thursday, October 23, 2008

Pictures of progress

Here's the 6 paddle blade blanks waiting to have their edges rounded and be joined onto the looms.


This is the forward bulkhead, as viewed from the cockpit. A fair bit of sanding still to do.

This is a closeup of the seat, showing how I recessed a washer into the ply using a 16mm spade bit. This gets the head of the screw close to being flush while reinforcing the hole, necessary since the screw head doesn't have much of a shoulder.


A bit shaky since it was taken on a pretty dull day, but even so I think you can see the sleek lines of the kayak in this shot.

Tuesday, October 21, 2008

Paddles

I made a start on the paddle blades last night. I made a template out of a rough piece and got it as symmetrical as possible before using it to mark out the others. To check the symmetry,I measured a centre line and marked it in both sides of the template, drew a corresponding line on a board, then drew round the template with the centres aligned. Then I flipped it over and re-aligned the centres and checked the curves had a similar profile as those drawn on the board.

I cut the paddle blanks oversize from 4mm ply off-cuts. I then planed them close to the line before putting 4 pieces (2 paddles worth) together and finishing the planing and profiling as a stack to get them all alike. The other two blanks were marked to match the slightly narrower loom and the profiles adjusted accordingly. I then trimmed about 15mm from the ends to just make them that bit smaller and more manageable for Sam.

Th next challenge is to make a jug to get the correct profile in the ends of the looms, and to get the profile faces at exactly 90 degrees to each other on either end of the loom. I'm still thinking about that one. Meanwhile I'll get a bit of sanding done tonight, and take some photos too.

I'm favouring making a really neat job of the paddles. Partly because I want to prove I can, and partly because I think it might be less work to finish them bright (i.e. wood grain showing through layers of sealer and varnish).

Sunday, October 19, 2008

Sanding

I sanded on Friday night for about half an hour, and things looked encouraging. On Saturday afternoon I sanded for about 1 and a half hours, and I was less enthused. It looks like another hour or so will be required before a little more filler is added to the cockpit area, maybe another hour of sanding after that and then I can paint the cockpit.

I think this is the stage where it will be very easy to get demoralised.

On Saturday morning I went to by some timber for a garden project, as well as some kayak bits. I bought some nice straight pine for the cockpit stringers and 3 lengths of pine dowel, 2 at 30mm diameter and one at 28mm diameter. These will be the paddle looms, the smaller one will have slightly undersized blades and should prove a little easier for Sam to use at a similar stroke rate to an adult using a full size paddle. I'll work on the paddles while I'm waiting for resin to cure or paint to dry.

On Sunday I turned the other bits of timber into raised vegetable planters to make our garden a little more productive. I worked with Bridgit, which was mostly fun, and by the end of the day we had the planters correctly spaced and levelled ready to be filled with topsoil and brick pavers to be laid around and between. I don't know when it will all get finished, but it had better be soon because we need to get some vegetables planted now, really.

Thursday, October 16, 2008

Nearly ready for paint...

I got loads done today, nearly five hours on the boat, which is pretty incredible for a week night.

I started by sanding round all runners to smooth of the fillets I'd run and get rid of a couple of minor dribbles. Then I made some seat risers. The plans say to glue the seat in, but I'll leave mine mounted by screws to the bonded-in risers. That way I can take it out to recover it should the closed cell foam I plan to use for a cushion start to break up. It will also allow access to the area underneath, which if starts to deteriorate would otherwise go undetected. I screwed these risers into place and sanded down the interior to provide a key.

After dinner I went back out and had a monster session with the epoxy. First up I bonded in the seat risers and screwed them down until the resin sets. Then I primed out the entire interior to seal the wood. Some areas under glass tape was already done, but the centre area of each panel and the lower and inner edges of the inwales all needed to be done. Finally, I mixed up several big batches of low density filler to fair in all the tape edges.

All that will need a couple of days to go off before sanding, so if I do any building at all tomorrow (Friday) it'll be starting to make the paddles. They're $80 each in the shops, and I reckon I can make all 3 (one for this kayak and two for the tandem that is to follow) for less than that. On the other hand I might just kick back and have a beer or two, we'll see.

Wednesday, October 15, 2008

Things I've Learnt So Far...

The whole point of building the kayaks was to learn a little about the boat building process before tackling something bigger and more expensive. I've read extensively on other blogs, on boat designers web sites and in books borrowed from the library and from friends. Some of the snags I've encountered I've read about previously, because they seem to catch everybody out. I guess that means the first lesson is "There is no replacement for experience. Read all you like, but you don't know until you've done it."

So what are these common problems. The biggest surprise was handling the epoxy resin. It was also the area I had the most apprehension about. A common mistake, apparently is not mixing it thick enough when filleting or bonding. Now I've done that too. The epoxy by itself is about as viscous as maple syrup. It will run pretty much anywhere where its laid deep enough to not get soaked up by the wood grain. To make fillers it is mixed with small, low density spheres that bulk it up, thicken it and make it easier to sand. The spheres actually flow better than the resin, so it takes an awful lot of them to come up with a mix that defies gravity and stays where it is put. For bonding, the spheres are replaces by fibres that are so fine and short they look like dust. These thicken the mix more readily, but again I didn't use enough of them in the early stages. Its quite disheartening to watch that beautiful fillet that you've spent all the allotted 'wet' time shaping start slumping down the bilges into the bottom of the boat, just as the epoxy starts going off into its gel stage where it's no longer workable.

Tools I think I've got just about right. My two planes and my jigsaw get lot and lots of use. My cheap screwdrivers also seem to be getting a fair bit of use, usually while bonding up parts with epoxy, which now covers their handles, so its a good job they were cheap. I'm getting closer and closer to the dreaded sanding stage ready to paint the first boat. This may see some further tool expenditure in the form of an orbital sander. I have a very basic 1/3 sheet sander but it's so poor I usually find it quicker to put a 1/4 sheet round a cork block and use some elbow grease. Watch this space on the verdict of whether a power sander is worth its cost.

On timber, I think I got it right with the plywood, or if anything I maybe bought better than was required or the kayaks. That's by-the-by because anything bigger and of greater value would get the full-on BS1088 Marine Ply spec treatment, its silly to scrimp on the small difference in price per sheet between good ply and the best ply.

Where I got it wrong was with the finger-jointed softwood moulding I bought. Its OK for the inwales, they're really only there to provide a glue surface for the deck. The problem lies when I try to shape the stuff. Its very hard to plane a length of wood when the grain direction changes every 300-450mm. Because the grain changes direction and density, you can't use it to form a fair curve. It would be no good, for example, in forming a batten that was used to hag a plank off to derive the plank's shape. Again, I should have known this because I've read about other builders having trouble with finger-jointed softwood not curving well. Also, its not very strong. The same builders who can't get it to form a fair curve have also had it fail when bending over a tighter radius. I think I'll get some continuous lengths of 18mm square pine for the cockpit stringers before I put the deck on. After all, I've read the warnings from others and I know these parts are under stress when climbing in and out of the boat. It'll be one mistake I'm happy to learn from others making.

Tuesday, October 14, 2008

Running Strakes

I'm unsure as to what the correct name is for these parts, runners, strakes, false keel and bilge strakes, whatever. The point of them is to protect the thin-skinned kayak bottom from hidden nasties when launching and beaching. This is especially required since the beach most local to me is covered in oyster shells just below the high tide level.

The plans call for simple bevelling of the ends to provide a bit of streamlining and to please the eye a little more than a square-ended piece of wood. I went to town a bit while shaping the centre runner at the weekend, and had more fun with the two bilge runners.

To get them looking right, I only tapered their outer edges, leaving a straight line on the inner edge to run parallel to the longer centre runner. I paired up the pieces and planed them together to ensure good symmetry. Before stopping for dinner I managed to screw them temporarily in place, using a small offcut to get a constant distance from the centre piece. All the screws were placed from the inside, except on the aft ends of the bilge runners where the wood was too thin, so a round-headed screw and washer was used to hold down the end against the considerable curve of this part of the hull.

After dinner I went back to the garage and unscrewed the pieces to epoxy them on. The mix I used to fix the runners was a good thick microfibre blend. I glued and screwed each part back on to the boat before making some mixes of filler, part microfibre and part micro spheres, to fill any gaps between the edges of the runners and the hull. I also ran a tiny fillet against each edge to improve the look. By this time is was very dark, so sorry the photos are so glary, all were done by flash. I discovered, working at dusk in a lit garage, a benefit of the all-over Tyvek suit is it gives the mosquitoes very little bare skin to bite.

Sunday, October 12, 2008

A Little More Progress

On Wednesday I got in a bit of time to tidy up and sand back the filling done on Monday. Some of the deeper filled areas had sunk where the super-absorbent end grain had sucked all of the epoxy out of the filler mix, lowering the fill level.

On Thursday I got in a good session and taped all the outer seams. I got the tapes good and tight with no wrinkles or kinks. I went easier on the wetting out on top of the tape and was confident of a cleaner end result.

On Friday I finished shovelling the earth and chopping down the old pergola posts.

On Saturday Bridgit helped me to clear the overgrown shrubs by the fence and we moved the trampoline into its new position.

On Sunday I cleaned up the outer side of the hull to get rid of the drips. Despite the care I took not to put excessive amounts of epoxy on the tapes on Thursday, there were lots of run lines on the side panels where the gradient is steepest. I cleaned these up with a bit of planing and lots of careful scraping with the tip of a very sharp chisel. I can see now why a cabinet scraper is such a useful tool to boat builders. I also used some 60 grit aluminium oxide paper to rough up the tapes ready to receive more epoxy.

Finally, I managed to shape the false keel that will act as a running strip to prevent wear on the thin panels of the hull. The plans suggest a simple taper cut on each end, but I went to town a bit with a fairly blunt fore end and a finely tapered aft end. I screwed this in place temporarily from the inside to use it as a centre marker. The next step will be to add another couple of rubbing strips on the bilges and the centre false keel will act as a datum to ensure everything is perfectly symmetrical.

Monday, October 6, 2008

And finally, some boat building

I got home on Monday evening and was determined to spend a few hours in the garage on the kayak. It was raining quite a lot, so that ruled out digging clay, but I had to wrap things up early to go to the Land Rover Club meeting.

There was just enough time to sand the outer joints and fill the gaps and any remaining stitch/screw holes with a micro fibre mix of epoxy. I'm getting more confident with the stuff and made a good thick mix which went almost entirely where I wanted it to, and hardly at all where I didn't.

I also had a good go at the twisted keel line at the stern with the block plane and got rid of most of the twist. After I've taped the seem I'll add a little more filler to one side than the other and no one will ever know...

Photos from the Weekend


This is a giant weta. Its a fairly common group of insects in New Zealand, and this one, the biggest live one I have seen, had a body about 60mm long with antennae about 3 times that. It was hiding in one of the joints of the old pergola I took down. I'll have to make a pile of old wood nearby to re-home it.


Here's the trampoline that has taken over the garden...


...And this small pile of clay is covering the last part of the old concrete patio that the trampoline will be moved to. On the left you can just see...


...The monster pile of clay retained by the old pergola timber. There's just enough room left to fit the small pile in with this lot. The frame on the upturned table has rusted out and it will be going to the tip shortly.

Sunday, October 5, 2008

A Weekend in the Garden

We decided that it was time to do a bit of work on the garden. The new border that we created for the olive trees still wasn't finished, and we wanted to tidy the place up a bit before summer really gets going.

So on Saturday we went and loaded up the Land Rover with 180 litres of bark chippings and some more plants to finish thing off. I let Bridgit (a qualified seamstress) lay out the weed matting while I followed behind tucking it in to the edging strip. Once the last few plants were in and the bark was on, the whole lot looked much improved. So that's the view in one direction from the living room sorted.

In the other direction, we look out on to a huge trampoline that was gifted t me by a colleague. Sam loves it, and I have a quick bounce every now and again too. But its killing the grass and taking up too much space. We discussed the possibilities and decided that it would be great to move it over to a corner where an old rough concrete patio exits. Fine, apart from a spoil heap from a deck I built over a year ago currently fills the space.

I spent Sunday dismantling the very wonky pergola over the patio and recycling the wood into some temporary retaining. I then shovelled about 3 tonnes of soil and heavy clay from one side of the L-shaped concrete area to the other. I finished at about 7PM, totally exhausted but still with another tonne to move before the trampoline can be moved. And the weather doesn't look too clever for the next week, so it'll have to wait while I hide in the garage and get on with the kayak.

Photos to follow.

Thursday, October 2, 2008

Another slow week

I've only managed to get dribs and drabs of time on the boat again this week. Mostly its been tidying up after the weekend. I had about 4 dozen screws to remove from the inwales, and various drips and runs to try and clean up.

On Thursday I got out of work a little earlier than usual, but decided to go and get more supplies on the way home. I went to the Glue Guru on Wairau Rd, Glenfield for some cheap brushes and some West Systems 410 low density filler to add to the epoxy. So far I've used 411 blended filler that is slightly more dense and therefore harder to sand. Since the main use for it now is as a fairing compound to smooth everything out, I think ease of sanding is very important.

I got home and planed a bit of the boat. To get more room I took it out of the garage and up to the deck. It was he first time in a while I've seen the outside lines, and it does look very sleek. I've noticed a slight curve to the centreline in the last foot or so, as the chine angle increases to make the stern almost fin like. I suspect this will impart a fair amount of natural curve to the boats travel, so I need to do something about it. The problem was a less than perfect alignment of the ply panels before they were joined. A combination of planing down one side and filling on the other might remedy the situation to a degree.

I think, on balance, I prefer the time I've spend shaping the wooden pieces to the time I've spent in a one piece Tyvek suit, gloves and goggles, smearing gloop over the pieces of wood in an attempt to stick them together. I've got a few ideas that will make building the sister boat, a two man version of the Dart, easier, less frustrating, and hopefully more refined. Some of the woodworking tools have become firm favourites, especially the block plane that is a delight to use. I'm thinking a ply lapstrake boat like the Rogue will require plenty of shaping so the wood to gloop, joy to misery ratio should be higher than with the kayak.

I had to stop early on the Thursday to have a kick about of the rugby ball with Sam. Besides, the clouds were gathering so I couldn't have stayed outside much longer anyway. While he was waiting for me to pack up and play with him, I got Sam to take this picture. Bridgit obviously feels left out and sought to remedy the situation by getting in on the act, but she may regret it when she realises that her pushed-up nose on the window is on the web for all to see.


Sunday, September 28, 2008

Inside Taping

Saturday morning I rushed out to finish taping the inside joints in the hull. I had a little over half the length of the boat to do, for three seams, the centreline and the two chine seams. I also had to tape in the transom. I had to rush because at mid day we were going off to watch a rugby match. I was just soaking the last bit of tape when Sam's friend came round to come with us to the game.

We went to North Harbour Stadium in Albany where we met up with neighbours who had also 'borrowed' an extra child to watch the match. We went to see our local side, North Harbour, play Auckland in the Battle of the Bridge, the local derby in the NPC competition. Unfortunately North Harbour were beaten 22-29. On a positive side though, all the kids got an autograph and a chat from All Black Joe Rokocoko.

When we got back the weather had closed in and we spent the rest of the day indoors. Sunday was a different story though. Over night it had officially become spring with the introduction of daylight saving time, and outside it was bright and warm.

The first job I tacked was to glue on the inwales. I mixed some epoxy with plenty of micro fibres for extra strength and to fill any gaps. Once the hull was spread with a line of epoxy along the top edge, I screwed the inwales on using the holes I made when dry fitting, and added a few extra to pull everything in line where there were gaps.

With all the seams on the kayak taped up, I adjusted the corners on the bulkheads to account for the epoxy fillets under the tape and dry fitted all the athwartship pieces again. After a little fiddling I had all of them fitting quite snugly apart from the forward deck beam, which wasn't as wide as the boat any more. This I made right by pulling the boat together by a webbing strap attached to temporary screws in the top of the inwales.

Again, a micro fibre rich mix of epoxy was made up to glue the deck beams and bulkheads in place, making especially sure that there were no gaps left around the bulkheads. These will seal off an air-tight compartment at each end of the kayak, which provide flotation in the event of the boat getting swamped. Some of the pieces were wedged firm in the hull, others I added a couple of screws or tacks to keep firm while I added fillets of epoxy with low density micro balloons added before adding glass tape and neat epoxy to strengthen the joins.

Finally, I added pins to the centre of all the members, and to the point of the bow and the centre of the transom and ran a line to check everything was straight. There's a good line running right down the boat, with only the forward bulkhead out of line by maybe 3mm. Hopefully this will be reduced when the webbing strap comes off, and failing that, I should be able to pull it straight when fitting the deck.

Saturday, September 27, 2008

A Busy Week

Sam's school production, Roald Dahl's Goldilocks and the Three Bears (it's a court case attempting to bring Goldilocks to justice for rampaging through the bears' house) was on this week. It left very little time in the evenings what with practising lines and ferrying Sam to the theatre at the local college. And of course on Thursday we had to go and see the show for ourselves. Then on Friday I had the annual work's dinner so was only home long enough to wash and change.

So no work on the kayak all week. I did make up some flat pack storage cubes to try and help Sam tidy the inside of his play house (seen in the background of the strawberry planting scene in the previous post). I also made up a desktop out of pine boards to go across top of two of the storage units. Oh well, the clocks change at the weekend, so perhaps next week will be more productive.

Sunday, September 21, 2008

A Busy Weekend

Bridgit went away with work friends on a fishing weekend to the Bay of Islands, so I was on full-time child minding duties. Work on the kayak was restricted to a few minutes here and there tidying up the runs and lumps in the resin from when I taped the forward end of the boat. At least its ready for the aft end to be taped, and I'll try had to make a neater job of it. Advice I've read, and now have experience to trust and emphatically repeat is 'epoxy is a nightmare to sand, keep it neat and tidy in the first place, its way easier than cleaning up afterwards.'
The previous weekend we bought half-a-dozen strawberry plants for Sam to look after. On Saturday we went out to buy some timber to make a planter, some compost to plant them up into, and some straw to mulch them with. We got everything but the straw. I bought 150x19mm fence palings 1.2m long and some 40x60mm wooden pegs, 600mm long. I kept the design simple and got Sam involved marking and drilling the clearance holes for the nails, a bit of nailing (but he's a lousy aim) an generally letting him know what was being done at each stage and why. He got busy with friends in the afternoon so we didn't get the strawberries planted until Sunday evening when the sun was off them.



On Sunday morning we went over to Takapuna so Sam could pick up a library book he'd reserved. We took a mooch around the market while we were there, and I found a gem on a second-hand tool store. I got a curved sole spoke shave for $20, in good rust free condition. They are $87 new, and I was reluctant to spend that much on a tool that won't see huge amounts of use. I cleaned and sharpened it and gave it a try. All seems well and it should be good for shaping the cockpit hole one I get the deck on in about a week's time.

Thursday, September 18, 2008

Steady Progress

I got a couple of hours on the kayak yesterday. I laid fillets of epoxy thickened with micro balloons laid down the joints. These fillets are not so much structural as to provide a gentle transition from one panel to another. I did all three seems on the forward half of the boat.

Once the fillets were in place, I laid lengths of the glass tape on the still uncured fillets and then wetted the tape out with straight epoxy.

I'm finding the epoxy part of the process quite a challenge, and although I'm learning lots, I'm afraid that the kayak won't be too pretty when I'm done. I'm gaining confidence in mixing the filleting or jointing additives thick enough not to run and slump, but getting the tape to sit nice and flat is also a problem. I'll not worry too much about the seams that will be hidden in the fore and aft air tight chambers, but I suspect I have a lot of difficult epoxy sanding and smoothing to do to the mid section that will be seen through the cockpit opening. I hope I can make a neater job of the outer seams.

Tuesday, September 16, 2008

A Few Photos

I went out to do a bit of preparation last night, and was already to lay some epoxy fillets and glass tape over the hull seams. I went in for dinner and by the time I was done the night had chilled off too much for the epoxy to safely cure. In the meantime, here are a few pictures of the details covered over the weekend.


The above shot shows the difference in the profiles of rear bulkheads MK2 and MK3. The latest (the one that fits) is on top, and shows a much steeper vee to the bottom panels than the one taken from the plans.


This is a closeup of the scarf joint in the inwale, nailed to a a board but with a layer of builders polythene between the inwale and anything else wooden. This is so that I stood half a chance of separating the items after the epoxy over run had cured. Even so, pulling that nail out of the joint took some effort.


Finally a view of the epoxy tabs that allow removal of the cable ties before laying the fillets and tape. I've prepped up the forward half of the boat and its still in one piece after removing about 3 dozen cable ties.

Sunday, September 14, 2008

Rear Bulkhead Version 3.0

Sunday morning was taken up with a trip to the library and Kings Plant Barn. I returned my copies of John Welsford's Backyard Boatbuilder and John Gardner's Dory Book and got some books on sea kayaking to make sure I 'll be prepared by the time launch date arrives. Since my partner, Bridgit, has suddenly decided to go all Earth Mother on us, we were at the garden centre to buy some olive trees and tomato plants, and Sam got some strawberry plants which no doubt he'll fail to look after.

When I finally got around to looking at the kayak, I decided it was time to address the rear bulkhead, the second version of which I failed to make fit while i was tweaking the lines of the hull on Saturday. It seems that as drawn, the transition between the steep vee of the transom and the relatively slack vee of the bulkhead less than 3 feet further forward is just too much for the 4mm plywood to take. In attempting to make the piece fit I was forcing the seams of the boat apart.

The solution, I decided after much pondering, was to make my own bulkhead according to the shape of my hull. I used the top profile of the existing part and carefully measured the width across the inwales, the width at the chines and the depth from a line between the chines and the centreline of the boat. These details were transferred onto a piece of cardboard, and when that fitted snugly, the shape was transferred onto 9mm ply and cut and planed to shape.

To finish for the day I took of the inwales and laid them out on a plastic covered board to scarf joint them with epoxy. I nailed the epoxy joint tight while it cured, and then used up the rest of the mix putting little dabs on all the hull panel joins, so that when I come to fillet and tape the seams I can take out all the cable ties first. The first mix was a bit too thin and worked OK on the centreline but it tended to run down from the chine joints. A second batch was made much thicker with extra microfibres and it all looked good when I closed the garage door on it for the night.

Saturday, September 13, 2008

Stringers

On Saturday I lost a significant chunk of the morning while waiting in line for a haircut with my son at the Birkenhead Corner Barbers. Once shorn, we took the Land Rover down to the Birkdale Timber World to pick up the softwood for the stringers and running strips. I didn't want to waste more of the day going further afield, and my friend Simon works there, a fellow Land Rover nut.

After talking Land Rovers for about 15 minutes, I selected some fairly cheap 18mm square finger jointed softwood. Its not great stuff, but since the designer had e-mailed me back with some details about its purpose in the boat, I decided that it was more than up to the job. Basically, as in any true stitch and tape boat design, the plywood monocoque provided the boat with all its strength, and the stringers are there primarily to provide a gluing surface where a more usual epoxy fillet and glass tape join can't be made, i.e. in fitting the deck to the kayak, where no internal access is possible.

The rest of the day was spent tweaking the kayak hull and fitting the stringers along the top edge with screws, ready to be epoxied on later. I also spent a while planing the bottom inner corner of the stringers. This will remove a little bit of weight, since the timber I'm using is slightly over sized from the original specification.

While sanding one of these pieces, I had a bit of a mishap. My ring finger got caught in one of the accessory holes in the top of my portable workbench. It's ripped a lump of finger-tip away, I managed to stick it back down with a plaster and stem the blood, but it was very sore. I was using sharp tools all day, planes, saws, chisels and the jigsaw, and I managed to wound myself on a blunt work bench!

Thursday, September 11, 2008

Stitch That!

So tonight it was out with the drill and the cable ties and time to stitch the panels together.

It was a fairly easy process, I marked out the chine edge on the bottom and side panels with a straight off-cut of ply, following the curves so that the holes would match up. The instructions say to start at the stern and work forwards. This made for wobbly initial progress, 14' long thin ply planks have a mind of their own.

The last part to go on was the transom, after bracing the gunwales 610mm apart. All of a sudden this loose and floppy mess held its shape and I could see how it could become a kayak. I kept the stitches fairly loose, I won't tighten them until I've made a few adjustments and got a good test fit of the deck beams and bulkheads.

Tomorrow I'll buy the softwood for the inwales, cockpit stringers and runners and get everything aligned ready to start filleting and taping the main seams. I'll also add photos to this post, I can't seem to do it from home since changing ISP.
See, I told you it was a kayak I was making!

Wednesday, September 10, 2008

A Slow Day

Unfortunately I had to do some real work this evening so no real progress on the kayak. I spent a few moments trimming the excess glass and resin from the glass strap butt joints, ready to start stitching, and that was it really.

I also made room for the assembled kayak by moving the Mini over to one side of the garage. Pushing it was made easier by pumping up the flat front tyre, and I then steered it close to the wall, but annoyingly I couldn't get the back end to tuck in as neatly. The solution was to grab the rear of the car by the wheel arch seams and pick it up and shove it over. Job done!

Tuesday, September 9, 2008

Taping the Other Side

Last night's boat building went very smoothly compared to the previous few days. The planks were all warm and dry in the garage, so it was simply a matter taping the other side of the join.

Where a lot of resin had soaked through from the first side I sanded with some 150 grit paper to give the new epoxy a surface it could key to. I'm fed up messing around with food wrap, its very difficult to get the wrinkles out of, and any wrinkles cause an impression to be cast into the resin. Instead I laid the planks over an offcut of thick builders polythene sheet.

I used lots of epoxy to soak into the glass, making sure it all went nice and transparent. This indicates that there are no dry spots or air bubbles. After an hour, by which time the cure should have been well into the gel phase, I went back to check it all looked OK and locked the garage door on it all for another 24 hours.

I've just had a reply from the designer regarding a couple of points with the bulkhead and bottom runner sizes, thanks Paul. Since I should be ready to start stitching the hull this evening, I can also now go and buy some softwood, the last structural components of the kayak. It should be looking boat-shaped by the weekend.

Monday, September 8, 2008

The Day After the Storm

What a nightmare - I put the 'tent' up over my kayak pices on the east side of the house. Its the most sheltered side and usually bad weather comes in from the west. Last night we had a howling wind and lots of heavy rain from the east, and it blew against the side of the house and down the back of the tarp. One of the planks got wet. It was mainly at one end, and the joint appears to be OK. I lifted all the pieces and put them in the garage, under the mini. I'll take a better look after work tomorrow and hopefully tape the other side then. At this rate it'll be Friday before I'm ready to start stitching the hull together.

Saturday, September 6, 2008

Epoxy Again

This Sunday is Father's Day in New Zealand, so it was a leisurely start after a nice breakfast out at Verran's Cafe (French toast with bacon, berry coulis, grilled banana and maple syrup, if you're interested). When we got back to the house I lifted the tarp at the top of the driveway and un-piled the bricks and boards from the ply. What I found didn't look good, it was almost like a continuous bubble had formed between the ply and the glass, and I was able to lift the glass off with nothing more than a firm pull.

I got myself appropriately dressed and protected and sanded off all the epoxy from the previous day and then set about preparing to re-do the job. Knowing that the wet time and the cure time are two totally different things, I wanted a place that could be left undisturbed and where I could shelter the parts from the weather. As it happens the bit of deck outside the back door is just wide enough for all four planks, and is mostly covered by the house's wide eaves.

I laid down some flat boards, covering the centre one with food wrap, and then laid out and aligned the parts. The far ends I held in place with boards and bricks as before, but near the join to be made I used ply off-cuts nailed down through the board below. Before getting on with the epoxy, I lashed the four 8' fence posts to the deck rail to hold a tarp up when I was done.

I was almost better prepared this time, wetting out all the parts with neat epoxy before adding the microfibres to get a gap-filling strong bonding agent. Then I realised that I'd forgotten the glass tape, so I charged down to the garage, past a bemused neighbour (I was in a white chemical protection suit, dark glasses and medical style disposable gloves remember) got the glass and was back again in less than a minute. I cut generous lengths of glass tape and laid them over the wetted joins before squeegeeing the thickened epoxy over and into the tape and joins. When I was happy that all the tape was properly wetted, I laid another board covered in food wrap over the top and then piled on a few bricks to try and get the ends of the fairly springy ply to sit flat and level.

This was a fairly frantic process, and I carried on by putting the tarp over the fence posts and tidying up before stopping to get the camera out. But you should be able to see that I negated any chance of the ply moving until I decide its time. Hopefully this join will be good and I can turn the pieces over and tape the other side tomorrow evening.

Saturday Afternoon - Epoxy Time

So there was no more putting it off, it was time to use the epoxy.

This is the bit I am most wary of. The most careful woodwork could easily be trashed by carelessness with the stick stuff, and I could trash a load of other things too if I get too messy.

The first thing to do on the kayak with regards to epoxying is to join the fore and aft pieces of the four hull panels to their full 14' length.

My plan was to lay out the master parts that I cut on day one of the build, tape and epoxy them, lay plastic food wrap over the join and then lay the other panels on top to get their alignment spot on and then tape and epoxy those. That plan turned out to be far too ambitious. The ply, even at only 4mm thick, has quite a spring to it, and as soon as I lifted some of the weights, the joints lifted on one side, bringing the tape with them. I quickly weighted it all back down again and went to do something else.

My son has a little basketball hoop that clips over the top edge of his bedroom door. The only trouble is that when its in place, the door doesn't shut and then the door frame blocks half of the basket. After I decorated the hallway I promised him I'd make a permanent backboard to mount the hoop on. While I waited for the epoxy to cure, I cut the backboard from 10mm MDF and then measured and drilled the hoop mounting holes. I masked up and sprayed the lines using some left over black enamel, then gave a clear lacquer coating to the bare MDF. Mounted up I think it looks pretty good, and Sam was really happy with it.



Well, it was time to check on the epoxy. A test piece in the garage still hadn't gone into the final cure state, although with the increased volume and therefore exothermic heat, the leftover epoxy in the pot had gone rock hard. Although it was a beautiful warm day, its only just getting in to spring and it cools off quite quickly. I suspect that out on the driveway under the boards and bricks, the kayak panels still won't have cured by the morning. I covered them with a polytarp and more bricks round the outside, and we'll see what the morning brings.

Saturday Morning - Tidying

Before any more work could be done on the kayak, I needed to tidy the garage. Apparently, the key to working with epoxy is being organised and tidy. I wanted a store to keep the epoxy containers with their pumps mounted that I could use and pack away with the minimum of fuss and the minimum of risk of getting resin all over things it shouldn't.



To this end I cleared a space in the corner of the garage near the door. For my epoxy storage unit, I used an old heavy duty plastic document container that I had previously made a lid for to use as a tool and recovery gear box in the back of the Land Rover. I chocked it up on blocks and screwed through its base into the block wall to keep it stood on its side. I used a piece of scrap board as a false floor, packed up at the front to bring the tapered box side back to near-enough level, and used a bit of redundant flat-pack computer desk to make a shelf over the top. The bungee cord closing was the same as had been used in the Land Rover, but I moved the cleat to on top of the shelf for easier access.



The beauty of this arrangement is that I just have to pull the containers onto the open lid/door to use them, and any spills should be restricted to this easily replaced piece of board. Perhaps I should cover it with some polythene sheet that can be pulled of and thrown away, allowing the door to be closed with no fear of it being bonded shut when I return the next day.

Before I stopped for lunch I went and got some safety equipment. For using the epoxy I wanted vinyl gloves (I find the latex ones far too flimsy), some good glasses that wouldn't keep slipping, a cover-all disposable suit and some masks that would be up to blocking the fine sanding dust. I went to the the Archer's Road branch of Protector Safety, where a very nice man soon had me fully outfitted for a mere $55.

Thursday, September 4, 2008

Friday - a day off from the build

No boat building today, but I was working at a customer site in Albany, close to the PlyMan. I took the opportunity to call in and buy the West System Epoxy components required. I got 4 litres of resin, 800ml of slow hardener, some low density filling additives and some microfibres, and the mini pump system that makes measuring and mixing simple and mess free.

I then tried to find Fibreglass Supplies to buy some tape, but got a bit lost in an industrial estate (I hadn't checked them on a map before leaving and was winging it). Just then the customer called me back on the cell phone, so I pulled over to take the call. As I was talking them through their support issue, I realised I was staring straight at the sign for Fibreglass supplies.

Although PlyMan could have sold me 100mm tape, it would have cost over twice as much as the 75mm tape I really wanted as sold by Fibreglass Supplies, and I was going to get the epoxy from the Glue Guru, but noticed it in the PlyMan when I bought the ply last weekend, and it was a good few dollars cheaper. It just goes to show how a bit of shopping around can save a few bucks if you have the time and patience.

Deck Beams, Bulkheads and the Transom - Part 2

I got home from work at about 4:30 after a very early start. The weather is definitely getting better, so the first thing to do was get changed into shorts. The second thing was to make some lemonade. Take a lemon fresh off the tree (larger than I've ever seen in a green grocer's and lots more juice) and squeeze the juice into a tall glass. Add water and drink.


Fully refreshed it was time to complete the athwart ship members. The good news was that on closer inspection, the deck beam that I thought I'd stuffed up was salvageable. The only deep scoring is across the corner that will be cut out to make way for the cockpit stringers, so no real drama.


In order to finish the deck beams, I needed to fashion a rounded sanding block, since a spokeshave had failed to materialise during the course of the day. A bit of scrap timber and a minute or so with my cheapo No.4 smoothing plane followed by a minute with the block plane and a very quick sand and I was ready to go. Using this on the deck beam undersides with some 80 grit paper wasn't a whole lot slower than planing the top edges, although I cut a lot closer to
the line on the undersides, predicting this situation.


All the other pieces went quite well apart from planing the slight curves in the bottom angles of one of the bulkheads. I completely overshot the centre line and had to remake the piece. Since I had the plans back in the garage to mark out the replacement bulkhead (less serious than the deck beam since it uses a lot less ply) I decided to check the profiles of all the pieces. To my delight, all were well within what I consider to be acceptable tolerances. We shall see for real when I start stitching the pieces together at the weekend.

Wednesday, September 3, 2008

Deck Beams, Bulkheads and the Transom

Last night I tried to get out all the athwart ship parts from a sheet of 9mm ply. Rather than using a table of offsets, these parts are shown as a full scale half-profile on the plans.

Step 1 was to hold the plans up to a window and carefully draw on the back of the half profiles, including the centre line.

Step 2 was to draw a centre line on the ply and pin the plans on top, taking care to place the pins through the centre line on both the plan and the wood.

Step 3 was to use an awl to poke marks through the plan into the wood on all the corners plus plenty of points along the curves.

Step 4 was to unpin the plans and then carefully pin them back again using the same pin holes but with the plans turned over.

Step 5 was to repeat step 3 to produce the other half of the profile.

Step 6 was to carefully join the awl marks with a pencil line. Note that although I marked the positions of the stringer cutouts, I don't intend to cut these until I've sourced my softwood since it is unlikely to match the dimensions given on the plans.

Step 7 was to cut the parts out. I only cut out the two deck beams using a different jigsaw blade to the course one I used for the hull parts. The fine blade gave a much nicer cut, but light was fading and I was finding it difficult to follow the line, so I stopped before I wasted any wood.

Step 8 was to trim up the parts right up to the line. I only did this to one of the deck beams. The straight ends I decided to cut with a panel saw to get a good, straight edge. This would have been fine if the saw hadn't of slipped and scratched the surface of the part. This was when I knew i was rushing and was getting sloppy, so time to stop work.

Given that the one deck beam was likely to be scrap now, I experimented with trimming the outer curve. The Stanley Bailey block plane made very short work of this, I love that tool.

The inner edge presents more of a problem though. Some of the concave curves on the hull parts were just about manageable with the block plane, given their very gentle curve. But the deck beams have a quite tight radius to their undersides, and for this I need a spoke shave.

All the usual outlets have drawn a blank on this front, so I'm going to check out the second hand tool stores at the Takapuna market on Sunday, keep my eyes open on TradeMe and see if I can beg steal or borrow one from anyone I know. Failing that it'll be course sandpaper round a piece of thick dowel.

I'll add photos to this post later, to show the marking out process.

Photo of the marking out process, as promised.