Cedar Strip canoe build

[Bill]

Hi all,

 

As I am undertaking a boat build it seems appropriate to start a build blog. This however will not be the usual NB fitout jobbie. I have just started on building a 14'10" explorer open Canadian cedar strip canoe. This will be used alongside my NB (The Midnight Owl) as a tender/playing about boat.

The process begins by obtaining a set of plans and various bits of wood to build what is known as a strongback. This is a box section structure about 15ft long on which to mount the mould sections which form the shape of the boat.

The moulds (13 of them) are cut from MDF after marking the shape of each from the plan. I currently have about half of them cut. When the shops open tomorrow I can get more wood to do the rest.

 

Moulds cut so far

 

Edited January 1, 2013 by Bill

[Tonka]

Have you also checked out "Song of The Paddle" canoe forum

[Bill]

Have you also checked out "Song of The Paddle" canoe forum

Not recently, but I will when I get a few moments, thanks for the reminder I had forgotten all about that one.

[Bill]

Getting on with the build, the strongback is now built and the moulds placed and aligned. The moulds now need fairing (edges chamfering to accommodate the cedar strips so they lay flat) and a few lumps and bumps need sorting. Cedar strips are due this week so need to get on and get ready. The whole garage now smells like a woodyard and I'm beginning to hate wearing a dust mask all the time (but preferable to getting MDF lung or some horrible ailment).

 

The whole jig needs to be covered where the wood will be glued (I'll use packing tape as its quick and cheap) so the finished hull can be removed.

 

 

Next build job is to laminate the stem and stern section from thin strips of wood bonded with epoxy (the bit with all the spring clamps in the photo).

[Batavia]

Please keep up the blog, with plenty of details. I have been wanting to build a strip plank canoe for years, but it has never reached the top of the pile of things to be done. Perhaps in a few years time........

 

Is it a Selway Fisher design?

 

Our neighbour is currently building a strip planked 26' Edwardian launch - as his first attempt at boat building!

 

Chris G

[Dovetail]

Good luck Bill I will watch out for more posts in the future. I have worked with plenty of Cedar in the past but not in the thin strips you will be working it’s a great timber to work with and smells gorgeous.

You probably know and I assume it will be Western Red Cedar? make sure its Canadian as the same timber grown in the UK is different from growing conditions and looks good in its own right but not as good as Canadian.

[Bill]

Yep its a Selway Fisher Explorer, open canoe. Very nice plans to work with (full size mould sections, so no scaling or messing about). The instructions are limited and it does say that this particular design is not ideally suited for a 1st time builder. But having fitted out a narrow boat, built a kit car (Spartan), and built various models over the years I figured I'd be OK .

 

 

Yes it is Western Red Cedar but to be honest I don't know where it was grown, it is kiln dried and clear grade (i.e. no knots) but I'll have a word with my supplier to find out where it came from. He is also supplying ash for the gunwales and I assume this will be British (should be dirt cheap given the Ash die back disease that is kicking about).

[Jerra]

He is also supplying ash for the gunwales and I assume this will be British (should be dirt cheap given the Ash die back disease that is kicking about).

 

I wouldn't like to bet the wood will be cheap due to Ash Die back! The Forestry Commission say

 

The implications for growers of ash for the timber trade would be significant if the disease were to become established in Britain. The timber in infected trees might still be usable for some purposes, although staining by the fungus might limit the range of end uses. However, it is not currently possible to move ash material out of confirmed infected woodlands or other sites which have been served with a Statutory Plant Health Notice.

[Dovetail]

Probably a high chance it will be Canadian Cedar Bill especially as you say knot free. UK Cedar can be knot free but its more difficult and wasteful achieving it, also its not as easily sourced I had to supply it for a job and it took a few calls to get some and then had the trees cut to my requirements and dry the timber whereas I could have had a lorry load delivered within a week of imported Canadian Cedar. Good luck with the build.

 

Just to add Canadian Cedar is rarely kiln dried and is often shipped green but Cedar does dry very fast and stays reasonably stable. I have taken delivery of 12”x2” boards soaking wet and when stood on end a small puddle of water can form around the board but within a few weeks it can be almost perfectly dry for machining. You should have no problem with the strips you are getting.

Edited January 8, 2013 by Dovetail

[ditchcrawler]

O I want one.

[Bill]

Glued up the inner stem around template using West System Epoxy (nearly forgot to put tape on the template prior to gluing it up ). Hopefully when it has cured it will maintain the shape and I can transfer it to the build jig.

 

 

If all goes well I'll do one for the other end tomorrow.

[Bill]

Now have the stem and stern inners on the moulds. The screws are removed once all the strips have been epoxyed to them. The 1st strips are in place (once again screwed to provide a solid starting point). The screws are removed prior to glassing the outside and the screw holes are covered by the gunwales when they are eventually fitted. The epoxy I have (West system) is OK down to about 5C, but its a bit colder than that in the garage so I'll hold off until it warms up a bit. When I took the photo below I thought it all looked a bit pissed, turns out the lamps on the workbench cast shadows which made everything look lopsided (it's not, I measured it all again to make sure ).

 

 

At least the cold weather is stopping me rushing things as I can't feel my toes after 30 minutes and my fingers feel like they belong to someone else.

[Chris Pink]

What do reckon the cost of the project Bill?

 

Lovely bit of work.

[Bill]

What do reckon the cost of the project Bill?

 

Lovely bit of work.

 

 

Not cheap, probably about £750ish in materials

 

£420 cedar (much cheaper if you do not want bead and cove, or have the machinery to do it yourself)

£25 ash (gunwales)

£60 strongback (Ply, 3x2's, screws)

£70 epoxy, meter pumps, stirrers (tongue depressors)(I'm using clean tin cans as mixing tubs)

£110 woven fibreglass, resin, hardner, sqeegee, roller, brushes

£75 misc (should cover wood for seats, thwarts, varnish etc etc)

 

Fortunately I had most of the tools I need, needed a few more clamps and other small bits and bobs. Will be worth it though once its done. As I enjoy pottering in the garage I would only be doing some other project. So given the four or five months I expect it to take I recon its money well spent.

[Bill]

Its been a bit cold of late so progress has been slow. Only managing to get one or two strips a day in place due to the long hardening times of the adhesive. I am using what is known as the clamp method which does not use staples. This means that the individual strips can only be done one at a time and are held in place with a small wooden jig and a G clamp until the glue has set. The beauty of this method is that there are no staples to pull later on, also no little holes to fill and make good. Some people use small wedges under the jigs to apply pressure and make sure the strips lie flat against the moulds. I found this to be both very fiddly and tedious to do, so I found another way. I used a small length of thick plastic coated wire (red bit in the photo) which has a small amount of give (considered neoprene tube but this was too squishy), I then pushed the jig hard against the mould and tightened the clamp, Gives just the right amound of clamping pressure and does not damage the cove. Starting to see the lovely curves appearing as the strips get added. The white marks on the wood are dried adhesive which will be removed at the end when the whole thing is sanded.

 

[Bill]

Now the warmer weather is here the progress is starting to happen. It's quite difficult keeping tight against the mould so I have resorted to using small wedges when required, seems to do the job.

 

 

 

The camera flash makes everything look blotchy, I'm tempted to sand some of it now just to see what it looks like, but I'll probably leave it until then end. You can really start to see the curves coming out as you turn from the sides to the bottom. The wood takes quite a twist from near horizontal in the middle to nearly vertical at the stems. Using small width strips helps as you can twist them without resorting to steam bending (which the ash gunwales will definitely need). The last few strips are supposed to be a real pain to get right but to be fair it has not been that difficult so far, just apply pressure and clamp up tight till the glue is dry, when you remove the clamps everything stays in place.

[Chris Pink]

Wonderful job Bill, truly wonderful.

 

I've bent 1 x 1 ash around a tighter curve than that simply by leaving it the canal for a while - if you haven't got easy access to steaming equipment.

 

have you planed a bevel on the edges of the planks? or do they just fit so well because they are thin?

[Dovetail]

You are cracking on Bill it is looking great don’t worry about the wedges, I have a saying “don’t underestimate the power of the wedge” it’s a great tool.

Ash lends itself to bending that’s why it was used in plenty of early cars as it tends not to split. Try pre bending no steam and then increase the bend over a couple of days something as simple as rope/ string like a large bow may do it but you will have to bend it beyond the final bend as it will want to spring back some extent.

[Bill]

Wonderful job Bill, truly wonderful.

 

I've bent 1 x 1 ash around a tighter curve than that simply by leaving it the canal for a while - if you haven't got easy access to steaming equipment.

 

have you planed a bevel on the edges of the planks? or do they just fit so well because they are thin?

 

 

The edges are bead and cove, one side concave the other convex, so they sort of interlock even when at a slight angle (i.e. when turning the bilge). The beauty of that is that once sanded back the very small joint virtually disappears. I do have a pressure steamer which I can link up to some large bore pipe so I will try that when the time comes. I think I will try bending dry (or soaked in hot water 1st) but as the gunwales are recurved (bend back out at the stems) it may be easier to add a little heat to the mix. I'll see how it goes.

[Bill]

Nearly there with the planking. The cold has once again slowed things down a bit but the last couple of days have been much quicker. Each individual piece now has to be cut and trimmed to size which is time consuming but very satisfying when it slots in with nice neat joints.

 

 

The end is notched ready to take the hardwood stem outer. I've decided to use a dark wood to contrast the relatively light cedar.

 

 

Then it is sanding time, given the good fit of the planking it should only take a couple of hours to fair in the stems and give the whole thing a good rub down. I'm planning to put 1 coat of resin on before the woven mat, that should seal any minor pinholes and stop any bubbles forming during glassing. Really looking forward to the glass fibre work as its years since I did any (and that was patching up an old banger).

[Dovetail]

Its looking great Bill is it just the last few planks and then do you take it of the mould, I bet that will be an exiting bit.

[Grace and Favour]

Bill - that's a superb job you're making there, Sir! Superb!

 

(But I hate to mention - - has anyone pointed out that you're building it upside down?)

[Bill]

It stays on the mould until the outside glassing is done. Then off it comes and is flipped over to do the inside (I understand sanding the inside is a bit harder/fiddlier to do). Then it will be glassed inside making a cedar sandwich.

 

And no, it's not upside down, I'm planning on using scuba gear otherwise I'd have to come up every couple of minutes for air

Edited March 6, 2013 by Bill

[IainW]

looks great!

[Bill]

Hardwood stem and stern now on, all planking finished, had it's first rub down and it is now all quite smooth.

 

 

Another rub down or two and it will be ready for the glass to go on. Got to wait until the weather improves as ideally it needs to be over 15C to make sure that it cures crystal clear (the way things are going I expect that will be sometime in August ).I wetted it down to raise the grain prior to its 1st rub down and the colours are amazing (I'll do some photos next time I wet it).

 

At least the cold will encourage me to go down and get the NB ready for the season, couple of odd jobs to do (re-seal flue, wire in some new lights, generally have a clean up after the winter). So not all bad