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


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.