Bulkheads - 1 out of 2 aint bad

Ok, so having wired the boat together, the manual casually mentions to flip the boat over and support it in mid-air on poles attached to the gunwhale (the top edge of the hull).  This is a faff, especially if you want the boat to be vaguely level.  The important thing is you don't want the bottom of the boat touching anything otherwise it won't assume the right shape.  The hull stays in this state, hung in mid-air until its been epoxied permanently in shape, so spend some time on this.

Looks like a boat to me!

I thought the next bit was to get the fibreglass out, so I was all prepped and ready for that until I realised I needed to make the bulkheads.  For the landlubber: bulkheads are the cross-section shapes that you'll see in a boat - internal walls if you will.  In bigger boats, these might be watertight, they might have doors in them, etc.  In the Chesapeake 16, there are 2 bulkheads, and these are drawn full-size in the plans.

First you make the bulkheads in cardboard - the reason will become sadly clear shortly.  Take the plans, lay them over some cardboard.   Use a bradawl or pin to transfer the lines from the plans to the cardboard.  Finally have some dot-to-dot childhood throwback time to join them up.  Simples!

So this all works great if they fit.  I was lucky - one of mine did!  The other, not so good.  Bulkheads for the kayak should not distort the shape of the hull - they should just fit to it, possibly drawing the sides in a little if they're loosely wired.


Well, I quickly cut the bulkhead out that fits from the wood.  Be warned - they don't make this clear in the manual, but follow the wood layout guide.  The bulkhead is cut from the 6mm ply (all else thus far being 4mm).  The 6mm piece is 4ft x 4ft and is mainly used for the bits that make up the coaming.  One of the bulkheads comes out of the middle bit of the coaming, so bear that in mind or you'll not have enough space on the board to draw out the other bits.  Fortunately, I had spotted this one!

It doesn't look too bad here, but trust me - its not right

So why didn't the other one fit, you ask?  Hmm - well I'm pretty confident of my measuring (I checked, ohhh I checked!), but I think this is one of those flexible things about boat building - by the time you've wired your panels together, they can assume a number of shapes, esp if you, like me, bought your own wood with its own bending abilities.  Its not that anything is wrong - tho always check, just in case!  Its just that every boat assembles differently.

If you look here, you'll see how far out this is

My next job therefore is to work out the shape from scratch.  If yours is a close, but inaccurate fit, you can adjust it, but mine wasn't wide enough, deep enough, etc and its easier I think to start again.  I've taken a while thinking this one out, and I'll certainly take any suggestions as its an awkward shape!  My current approach is drawing a line around the shape (you can see it faintly in the photo above) and then marking lengths, etc.  I layed a bar across the top and measured the drops to different points.  However, this isn't quite working, so I'm going to have to revisit this.

Thats about where I'm up to, tho we're approaching Christmas now and so I don't think I'm going to have much more time until we're the other side of it.  Its cold in the garage at the moment, so thats not helping.  You know what they say, you can't have your kayak and heat it!  (Sorry, its the only kayak joke I know - you were going to get it at some point!)

Merry Christmas and a Happy New year to one and all!  Pete

Slow but steady progress

So I have been somewhat remiss in keeping this blog up to date!  I can only apologise, although I have made some progress.  Not lots mind you - but it now looks like a boat!

I should probably explain my progress here, as it was always my intention to take my time here.  I'm not a boatbuilder, I'm a software engineer, I'm married and I have 2 young girls.  All of this keeps me quite busy, and the intention of the kayak project was that it was fun.  I'm lucky enough that we have a single garage that we don't keep the car in, and nobody really needs it for anything, so I can leave the kayak untouched without getting told off for weeks, even a month or 2 without being told off that its in the way!   This was quite important to me, because I'm building this for fun, and I don't have a lot of time always, so I really wanted to build something I'm proud of, but in a timeframe that suits me.  I get a lot of people asking me how its getting on, and whilst I'd always love to tell them of the vast changes I'd imagine myself making, I'm quite happy.

Having said that, I've probably failed to blog just as much as build, and have managed not to cover the most fun part of the project - putting the hull together and getting a boat shape!  To recap - I cut some 8 ft x 4ft boards into 11inch wide strips, then from those created (using scarf joints) 16ft long blanks.  I then plotted out the hull sections on them and cut them out.

The next step is to create the kayak shape - this is the "stitch" of "stitch and glue" construction.  Its quite simple to do, and allows you to take flat panels and create a kayak in under an hour!  This is magic - the hull is more or less monocoque (no internal framing) so the shape forms itself.

As it was a nice summer day (then, not now!) I did this outside on our grass, and my 5 yr old daughter (and the 3 yr old for a bit!) helped me do it.  This is highly recommended actually - its not too technical, and kids love the immediacy of this bit.  They also can't break anything provided they are told not to stand on the wood in no uncertain terms!  First, I cut up a load of copper wire into 4-5 inch lengths and put them into a tub.  4 inches is quite wasteful once these are in place, and it uses up a lot of wire to do that (I ordered a 2nd bundle of wire from Fyne boat kits in the end) but it makes it easy to work with whilst you are doing it.

Drill holes at equal lengths down the edges to join together (about every 6 inches, but more near detailed curves, etc) - the smallest drill bit you've got, just enough for the wire to poke through. 

Its an awesome hat - don't argue :)

The order of assembly is this - start with the bottom panels, and drill the bottom edge of them, and wire the whole length of the bottom.  Do not wind the wires tight - you want plenty of movement (think keyring sized loops).  This should effectively make you a panel that opens like a book.

Next drill the ends of the top panels (the very front edge of the boat, and the very back).  Wire these up.  This should get you 2 long panels with the ends wired, which you can open up in the middle.  Find your plans and find the distance from the bow (make sure you measure from the right end!) that the spreader stick needs to be placed.  This is just a scrap piece of wood, cut to a size to open the boat out.  This is exciting because you see the size and shape of the boat already.

At this stage, the upper panels are resting on the lower panels - they would fall through without the scrap wood separating them.

Next, lay some spare bits of wood on the upside down top-panels, and lay the open-book bottom panels on top.  You will want to do this on some trestles, because the panels won't marry up flat, you'll want to bend them (they're upside down, so this is effectively making them droop off the trestles) until they line up.  Next, you guessed it - wire them all together.  Voila! One kayak!

Stitching the upper and lower panels together

Stiffening up!

Yay! Back in the boat building game :).  So progress has been slow, but now I'm back on my feet I've picked things up again.  I'm now almost to the point where the boat can become a 3 dimensional thing so it's getting exciting, but let me back up and tell you whats been going on.

Having cut the boards to shape -initially with the circular saw, but I found this not to be too precise, despite what the books tell me.  The circular saw I have is probably a bit meaty for this bit, as you're supposed to be able to cut fair curves with a shallow setting of a small saw, but I was nervous and just stayed a few mm outside of the lines.  I suppose this was good because I found it takes almost no time at all to bring this right up to the pencil mark using my trusty block plane.  Taking a full 5mm off the plywood took me about 20 mins for the full length of the boat which, using the plane, can be controlled really accurately so highly recommended!

With the boards fully cut, the next job was to move on to the sheer clamps.  Sheer clamps are the name for the stiffening applied to the top edge of the side panels (in other words, they are inside the kayak, but on the joint between side and deck).  These are made of 1inch x 3/4 inch lumber.   (An aside here - you'll notice I've used imperial and metric measurements in the same article - deal with it, I'm British and we're seriously confused about our units - I use miles, feet/inches for height, grams for pasta and small distances in millimetres :).

Like the plywood, I needed to make the sheer clamps almost 16ft, and I was given 10ft lengths - time for the scarf joint to come out again!  In plywood, by far the easiest way to make this joint is to stack the wood into a ramp and plane it with a bench plane.  In lumber, you could do this, but it'd be hard work.  I decided to use my circular saw (Actually, I was going to use my table saw, but then I realised it was propping up the bench that I've been using to build the kayak, so durrr).

Scarf joints in lumber need to be 8:1  (12:1 if you're going to be making something critical like a mast or spar).  In other words, for 1inch lumber, this needed to be a 12 inch long diagonal cut.  First, I found 2 pieces of wood that I could use to make up a jig - 1 was the same height as my lumber, so that I could rest the wood next of it, both pieces being on top of the other part of the jig.  (I did have a photo of this, but I can't find it - will put it up if I do).  The idea was basically that the circular saw would sit flat on top of my piece of wood, cutting through the lumber next to it.

This worked ok, but I found that simply holding the 10ft long piece of wood was not a good idea when cutting - firstly because I don't like having too many things to do when playing with circular saws, but also because the wood tending to move slightly during the cut and thus shorten the length of the cut, messing up the angles.

The solution was to butt up a sacrificial piece of wood on the other side of the lumber, such that it was sandwiched in place and could not move.  The only thing to watch is where your nails are going so you don't send the saw through them.  Anyway, with this modification, everything cut much better.  A small application of epoxy and some time, and voila!  sheer clamps.

The next job was to then attach them to the side panels.  Fortunately I read the book at this point, and it helped remind me that by doing this, I was choosing which panels would become the outside of the boat.  Make mistakes slowly!  Anyway, I selected the best sides and after applying parcel tape to the top edge to prevent any stray epoxy getting on the wrong side, I set up for gluing.

This is the first part of the build which really calls for clamps.  I have about 14 spring clamps, 4 g-clamps and 2 bar clamps, which was just about enough.  G-clamps and bar-clamps are better because they noticeably apply more force, but the spring clamps are cheaper and easy to put on when the wood is sliding about on epoxy.  I've also heard you can make your own clamps by using pvc piping if you need more.

I was pleased with my epoxying, as much because I guessed the quantity of epoxy bang on - 1 full pump of resin, 1 full pump of hardener plus about 4 spoons of silica micro balloons was fine.  The sheer clamps need to stick up about 1/4 inch proud of the panel (so they can be planed at an angle later) so I marked that all the way along in pencil, and then used a brush to paint the epoxy onto the panel inside the lines.  After that, it was simply a clamping up job.  This was really nice, as I did it again 2 days later for the other side of the boat!

My next task is to drill holes along the (correct!) edge of the lower panels ready for wiring them together.  I also need to do the same for the upper panels (the ones with the sheer clamps on).  The bit after that is really exciting - I get to assemble the boat!  This is odd because stitch-and-glue boat building means that you get to do this whole bit in an hour or so, after which the boat is fully 3D, flat panels no more!  Due to limited space, this'll probably mean reconfiguring the garage again so the kayak can sit on the trestles, but at least I'll get my table saw back!

Normal service will resume shortly!

I don't know how many people are following this at the moment, but if you are thank you, its been a bit quiet from me I'm afraid.  I've been wiped out for a few months with illness, but that should hopefully be behind me and boatbuilding activites can resume.  The boat has not changed much, but the panels are all fully cut, planed and ready to go.  I've started cutting the sheer clamps to size and had a problem with cutting the wood accurately for the scarf joints - more to follow, but hopefully I should be back in business now.  Once the sheer clamps are glued together and attached, then I can do the fun bit of creating a 3-dimensional kayak out of all these pieces and actually stitch it all together!

And so, it has come to this....

So I've not done much on the kayak for a week or 2 apart from look at the garage longingly.  I did say this was a blog about trying to do this with a young family so I guess I deserved this, but with 2 kiddies and 1 wife ill with flu, I didn't really get that far (I know! they've got no sense of timing!).

Aaanyway, first night back in the garage and tonight's job was quite fun - to plot out 2 of the panels, so I guess this is the first "glimpse" of what we're going to be making!  This is effectively an X-Y plotting exercise, but you start by creating a straight baseline to plot your points from.  I scarved the panels pretty straight, but decided to play it safe and created a separate baseline anyway.  This I did with a chalk-line. 

This is my first experience of using a chalk-line, but I needed to make quite a long straight line and this is what everyone recommended.  I used my family's week of illness to buy one of amazon for 2 quid.  I would link it, but it was a bit rubbish so don't bother.  Firstly, I'll give you 2 guesses what it DOESN'T come with - lets think, I'm buying a long piece of string on a winder and ummm, oh yes, no chalk.  Stupid.  Easily fixed - one benefit of a young family is that we have an easel in the lounge.  Ok, yes I admit it, I stole their chalk, I feel bad, sort of, but I've not been able to boat-build dammit!  It was only a little bit! They could have it back, but I whacked it repeatedly with a hammer and chucked it in my new chalk-line!

I digress, back to boat.  I pulled the chalk-line taut and noticed that in places, it hovered a good inch over the wood - this comes of having to build a make-shift 16ft long bench.  Anyway, with a few adjustments, I got it pretty good, then 'pinged' the chalk to leave a mark. 

Chalk sold separately

As the chalkline is new and I've not got a lot of chalk stuck to it yet, I probably can't really blame it for not leaving a perfect line, but to be honest, I was hoping it'd do a bit better.  Anyway I used a long spirit level to firm up the line with a pencil and checked it was straight by stretching out the chalk-line again and also sighting down the length of it.  Hopefully good enough - I'm a bit paranoid about triple-checking at the moment, but that should be a good thing if it works!

Yep, thats the baby monitor by the spirit level :)

Having got my straight line, I had to go and find my plans, as this is where they first come into play.  When you design or build a boat, the plans are 2 dimensional, and funnily enough, are not full-size compared to the boat you're building (I'm told that you couldn't do this even if you wanted to because a printer wouldn't give you an accurate image at that length and you'd get stretch, etc).  You've therefore got a job to do called "lofting".  I first read about this on another blog - "the Unlikely Boat Builder" which I highly recommend and I've followed from the start, but anyway, read this article of John's on lofting if you're interested as its very good.

Here's a shot showing how 3 of the ply panels are layed out, and the offsets for the long panels.  I've removed some of the numbers because these are not my own plans and the purpose is to give you the idea, not to allow you to build a kayak without paying for the plans!

As I said, lofting is the process of plotting out the boat from the plans.  In my case, I don't have too big a job.  Take the boat panel in question as a 2-dimensional shape, and a baseline running underneath it.  Along that baseline, you then plot "stations" which are normally interesting points along that line at which we need to mark a vertical line.  This vertical line naturally will meet the panel at various points, and the plans give the offsets that you need to mark.  Simples!

Next job will be to make up a long bendy batten that I can use (in conjunction with some nails at the marks) to join the points into a fair line.  "Fair" in this context is important - it means that the line follows a good single curve from bow to stern and doesn't wiggle up and down the length of the boat.  I think my current plan is to use a bit more of my scrap plywood to make this up - this is where I get to see whether scarf joints really live up to their reputation of not creating flat spots when bent into a curve - still weighing this one up, but I think it'll be ok, at least to try.


I have 4 panels that make up the lower sides of the kayak - 2 bottom panels (gar-boards if you want to know the boaty term) and then 2 side panels each side.  CLC recommend, for obvious reasons, that you plot the panel out on one panel but cut 2 panels clamped together, thus ensuring the sides of the kayak are symmetrical.

Amusingly, cutting these panels out will actually mean I'm going to start the proper building manual for the kayak.  You can buy kits from CLC (or Fyne boats in the UK) which would allow you to skip what I've done thus far, apart from that you'd have to epoxy-glue a pre-cut scarf in the cut panels.  I didn't want to go that route as I thought it was a good lead-in to the project. 

Summary: One panel plotted out ready for drawing in the curve,  Night all!

Scarves in winter!

Ok job 2!

The not-necessarily eagle-eyed amongst you will note that I cut 8ft blanks from the wood I bought, when actually the boat is 16ft long.  I'm obviously therefore going to have to join some panels together.  At this stage I have 8 x 8ft blank panels, which will make 4 x 16ft long panels when this job is complete.

So how do we join the panels together? We'd like a joint in the wood that is not really going to show - a kayak has nice curving sides (even in a hard-chine hull like the Chesapeake) and we don't really want a flat spot in the curve half way down the boat where we created a simple butt joint (butt our 2 panels up against each other, then put a backing pad behind it).  The way to do this, keeping a single thickness of wood is to use a Scarf Joint.

Imagine you just put the 2 panels next to each other, and put glue between them - not very strong at all!  Now instead imagine that the point of contact was made larger by making it a diagonal slope - this creates a much larger surface area to glue against.  The recommended slope for such a joint is 8:1 or 12:1 (if you were doing a really structual joint under load like a mast).  That means for a 4mm thick panel, we need 8 x 4 = 32mm wide slope.

The manual and the internet describe a number of ways to create such a joint, such as using routers, belt sanders, etc but I've also read on the internet time and time again on other people's blogs that the best way is actually by hand, and however they try other techniques, they always gravitate back to the one I'm going for.  No point finding this the hard way me thinks, so lets stand on the shoulders of some giants and follow the recommendation: take your wood, and stack a number of panels on top of each other (I did 4 panels at a time).  Step the panels such that each end sticks out 32mm from the one above it.  Take your (sharpened!) bench plane and just plane down the slope - the steps set you at the right angle and provided you have a sharp plane, this is straight forward to do.

Having cut my 11inch wide blanks I had a 6inch slice of wood spare to play with, so I used this to have a practice.  It's worth doing, as you'll get an idea of how evenly you can plane the scarf.  I also think that at the beginning of a project, you sometimes need to have a few plays at things to convince yourself you're safe to get going.  Anyway, you should see how well you're doing because we're using ply, and therefore as you plane, you'll see the layers appear as a horizontal band.  If you've planed evenly, the bands will be straight.  The only thing I'll add is that I found the bottom most panel suffered a bit at the end when I tried this, so make sure you're planing on top of a hard surface.  This job is definitely easier with a sharp plane - I definitely noticed when mine got blunt and the difference when I resharpened it.

Right! Epoxy time!  This is good, but scary stuff!  Again, I used my test piece to have a little play with the epoxy before I started - I plan to do this as I go along with various bits so I can reduce the screw ups!

Epoxy is a 2 part plastic adhesive.  It has a resin, and a hardener which arrive separately.  When mixed, they cause a reaction and start to go hard.  As this reaction takes place, toxic vapour is given off, and the mixture will get warm (it didn't noticeably for me when I tried it, but I suspect will as I use larger quantities later).  The warmth speeds up the curing time, so its best to use shallow trays to spread the mixture out and stop it curing itself.  The other fiddle is you need to keep the resin and hardener stored at room temperature (18-20 degrees) or it starts to go off.  The vapour isn't good for you (and there are dire warnings about sanding semi-cured epoxy and breathing in the dust) - the long and short is take the safety instructions seriously with this puppy, and always wear vinyl gloves when handling it.

The building manual said to lay all 4 planks (well 8 halves at this stage) on top of each other and separate the layers using celophane.  You should then put epoxy between each layer and then clamp it down.  It warned that the diagonal joints of the scarves could slip apart as you clamp them, so you'll need to prevent that with clamps elsewhere on the wood.  Sounds relatively simple yes?

My work area!

Reality, as always, was not so.  Firstly, these are now 16 ft long bendy planks, and you're trying to line them up straight as this will make drawing on them easier if you have a good baseline.  Secondly, and this is a point I should have spotted, its a right PITA to glue the bottom planks when you've got 3 others stacked on top.  I didn't want to do one then the next separately because a) that would take ages and b) I don't have a huge space in the garage to store the planks all over the place gluing so I wanted this to work if I could do it sensibly.  I settled for using an array of chocks to lift the ends up in the air so I could get in to the lower layers to glue them.  I'm sorry I didn't get a picture of this (new to blogging, sorry!) as my head was definitely in epoxy mode!  Anyway, I did a bit of a dry run, and proved I could get it to work, then mixed up the epoxy and got going.  It all went reasonably well - I remembered advice about changing the vinyl gloves often - you don't want to have epoxy blobs everywhere because you couldn't be bothered to change them.

A close up of the joint

The joins on all the panels were pretty good - the dark bit is where the epoxy came out (probably put too much on, but I was worried that this is quite a critical joint and I didn't want to starve it - will get better at guessing quantities hopefully!).  It looks like its just wet, but its actually like a lump of smooth plastic or glass that sticks up a fraction of a millimeter.  Sanded down with my shiny new random-orbit sander, it looks good.  I'm glad I got the tapered join straight here as it will make the kayak look much better if the line is straight and not ragged.  I did have a few places where the celophane wasn't wide enough and the epoxy just caught the layer of wood stacked on top, but fortunately it was only a tiny amount - close call though, I'll have to be more careful.

My next task will be to draw on a baseline (any ideas how to get a 16ft long straight baseline anyone? Maybe I need to buy a chalkline..) then I can mark up the panel shapes from the planks.  More on this next time!

Blog - reboot!

I'll leave the posts below for posterity, and so that you know that I'm a real person and that delays are inevitable with a combination of time, young children and the necessity to rebuild the garage before I could start, but anyway, I'm restarting this blog now that I'm actually making proper progress!

The wood arrived in December just after Christmas.  A word of warning to those of you who want to buy marine ply for a kayak.  First, make sure you do actually buy Marine Ply not regular, or the whole project will have been for 'nowt before you start as you haven't taken it seriously :).

The other thing is that the wood for the Chesapeake 16 is 4mm thick (not that many other boats are a lot thicker) and you need to find somewhere to purchase it and deliver it.  That 2nd point is important because you don't want to be carting 4mm ply on your roofrack as this is an 8ft x 4ft board that is going to break if you have much windage on it going down the road.  In terms of marine ply orders, a kayak doesn't qualify as a particularly huge order, so make sure the guys you buy it from are happy to deliver it.  This will be great peace of mind when you don't have to play with roofracks and damaging your wood and you can simply accept or not accept the order when it arrives direct to your home :).

I was lucky enough to get my wood from a place called Bamptons where they did deliver and gave helpful advice about the wood types and what to do.  Highly recommended if you're in the Solent area in the UK.  I have 3 x 4mm full boards (8ft x 4ft) and 1 x 6mm half board (4ft x 4ft) plus 10ft lengths of spruce for the sheer clamps (the thin strips of wood that run around the inside top edge of the kayak to hold the deck on).

Ok - I'd already repeatedly digested the plans so I was pretty familiar with how to get started (as I mentioned before, it was great to be forced to read before starting because the temptation is to get down and dirty and one thing I want to make sure is I don't rush and mess things up here).

Job 1: Rip 2 of my 8ft x 4ft (4mm) boards into 11inch wide panels.  I used another piece of wood (an 8ft contiboard shelf actually) as a guide to run my circular saw down.  Measure 15 times, cut once :).  This was actually quite a moment for me, because this definitely left me with the thought "thats it, I've started, I've made some sawdust!".  I've then got 8ft x 11inch long blank panels.  There was then a pause as the epoxy hadn't arrived due to a mix up at the shippers, so I'll pause here too!