I received a request for the table of offsets for a lapstrake chebacco. Here I have posted an Excel file with all of the offsets in Feet-Inches-eighths and also mm for both the 19’6 and the 25’4 versions. I found it easier to work in mm here in Australia (Inch rulers and tape measures are available but not so common) so I created these spreadsheets to make the conversions. It will probably require a bit of studying to work out what you are looking at.

The first table for each boat shows the height above a base line of the buttockline at each station. You will need to refer to the drawing for the location of each station – you may notice that Phil numbered his stations in different directions for the 19′ and the 25′ versions. We will never know why. The base line is the bottom of the keel for the 19′ version and 2 inches below the bottom of the keel for the 25′ version (I assume Phil changed his mind somewhere in the design process about the depth of the keel – but kept the table of offsets.) The buttockline is the line where a vertical slice would go through the hull. The vertical slices are 12″, 24″, 30″ and 36″ from the centreline for the 19′ version, but only the 24″ buttock is given for the 25′ version. This table also has the height of the deck and bottom panel. It looks as if I have found a small error in Phil’s deck height at station 1 during my analysis.

The second table for each boat shows the width from the centreline (so-called “half breadth”) of the waterline at each station. The waterlines are the lines where horizontal slices meet the hull. This is just like the line where the water meets the hull when the boat is afloat.

In theory you could build a hull using only one of these tables – but in practice you need to cross reference some little details that can’t be worked out with only 1 table.

Andrew

Chebacco News 72 – Chris Smead’s Chocolate Moose Part 2

March 19, 2021 4 Replies

Chris’ project continues on through the pandemic – Great photos, well thought through build, it is going to be a sail boat comparable to any Chebacco out there. – it looks like there is a part 3 to come too. Chris writes:

I forget to mention that I glassed the bottom, all the way over the joint with the bilge panels. I did not glass around the keel or the topsides.

I started sewing the sails, a kit from Sailrite here in the States. This is the mizzen with panels joined but it still needs patches and all the edge work. My church was closed for a long time during the pandemic and it gave me a great opportunity to use the huge lobby floor as a sail loft!

I decided to paint the bottom before flipping the hull. I used latex floor enamel paint. It won’t have that glossy finish and maybe not the wearability of marine-grade paint, but it was easy to apply and clean up, as well as quick-drying and not so toxic to the people who live in my house (especially over the garage). Besides, this boat will live indoors, in my garage for the majority of its life! Painting revealed lots of imperfections to be filled and faired. That process is ongoing even today, but I had to get after the ones that would be harder to reach after the hull got turned over! Here I am getting ready to unfasten the hull from the strongback in preparation for turning over.

What a triumphant moment! Here we are basking in glory – a hull in one piece and right-side-up! I have a second-hand trailer shown here. It still needs to be fixed up, but I’ll block the whole thing up to continue working on the hull on top of the trailer.

I took off the front part (tongue?) because it had to fit in my garage. Wouldn’t you know it – I had to park it diagonally because my garage door wouldn’t otherwise clear the bow in the upright position. My “manning-esque” bench came apart and got reassigned.

In this picture, I am preparing the FG tape on the inside seams.

I gotta tell you, it’s a surreal feeling when I look at the upright hull. That bow is so high! I didn’t expect it to feel like such a rise. Once I gained the confidence to step aboard, I spent a long time sitting in the cockpit just looking around. So happy!

This is a dry fit of the rudder box. I just had to install it on that square hole in the hull. Man, it was hard to start cutting that hole (mentally).

I did some framing next, for the cockpit and deck. I thought about making a bridge deck. My decision against it came from wanting to keep a large cockpit, and a plan to use the floorboards to make a flat platform in any configuration needed.

Here you see the aft quarters and the framing just installed. You can also see the side deck, which overlaps the last bulkhead into the aft section a little bit. I did this because I couldn’t figure out how to make a trustworthy butt joint right on the bulkhead, so I’m going to make one here instead, with a patch of wood underneath.

Here you see the same method (if you can even dignify it by calling it a method) on the forward end. I also fit the cabin sides. I thought it would be easier to do this before decking.

I got some great advice from Jamie Orr about mast slot design and it helped me think about how the mast partner pieces must go together. I read some classic posts from chebacco.com discussing weather helm. P. Bolger reportedly experienced a sail on a Chebacco and found more weather helm than he would have liked. He said moving the mast forward 3 or 4 inches wouldn’t hurt. I agonized about this for a few days, tried some different pencil marks and clamping arrangements, and settled on 2.5 inches forward of the mark on the plans.

I made the roof from 2 layers of quarter-inch. You can see here I also made the seats (which are not yet glued down in this picture) and also the, shall we say, backrest. In the plans, this backrest extends upward into a vertical coaming. I’m going to attempt an angled-back coaming and attach it to the backrest.

Then I cut the companionway and mast slot out.

Someone gave me an old 3-pulley bandsaw that I finally figured out how to repair and use. I used it to rough out the Jonesport cleat.

I took a shot at the sliding hatch by first looking at some examples for bigger boats in “How to Build a Wooden Boat” by David C. McIntosh and Samuel F. Manning. Then I dumbed it down and cobbled this, keeping the rails in place while gluing so I don’t mess up the shape and the squareness all around. No, that’s not the roof – just some scrap scaffolding to hold the shape while the glue dries.

I tacked on the roof later and started thinking about how to make the windows. I want them to be simple. Bill Sampson reported (over 20 years ago on chebacco.com), “I did SYLVESTER’s portlights simply by cutting oval holes in the sides of the cabin and screwing1/8″ acrylic sheet on the inside, with some clear silicone sealant between.” I think I might do that and maybe put a plywood border on the outside?

Here are the aft deck pieces and also the side benches being glued down.

I mentioned that I wanted to angle the coaming and tried to figure out a good method. A local guy has a J. Welsford boat (I think it’s a Pathfinder) and I stopped by his garage. His boat has beautiful angled solid coaming and I checked the angle and height, then tried to carry the idea to my boat. Here is the block beside the cabin, cut to about 10 degrees.

I also glued little angled, cypress blocks right on top of Frame #5 to help hold the coaming and also to place an oarlock someday. I sat against the coaming for a while after the epoxy cured. They seem pretty comfortable! Fellow chebacconist Howard Sharp suggested I also angle back the benches for comfort, but I decided not to try because of all the drainage engineering it would’ve required.

Here are the slots for the companionway boards. Some glue ended up curing in the slots and I didn’t notice for days after. I’m having to scrape as much as I can reach. Also, I’m shaving down the boards so they will fit the slot.

These aft-quarter coaming pieces had to match the rest of the coaming in curvature, so I had to carefully brace them in the right position while gluing. I still haven’t worked out all the mainsheet traveller and mizzen sheeting arrangement back here. Plus, there will be some kind of hatch for storage. I made the clamshell vents too.

I glassed the joint between the cabin and deck. I’m not sure if it was necessary, but it seemed weak and I didn’t want to worry about it.

I named it “Chocolate Moose.” I’ve tried on all kinds of other names. Some were more cheeky, some were more serious, even borderline profound, but they didn’t fit. A moose is a majestic animal, brave, large, fierce, strong and peaceful. On the other hand, one can’t escape the fact that a moose has a certain, unavoidable tinge of ridiculousness woven into its very identity. Yes, a moose is ridiculous. I mean, just look at that nose and those big ol’ antlers! This mix of character reflects my boat, I believe.

(Brittanica)

(Rocky and Bullwinkle)

But even beyond these kinds of moose lies the best mousse of all! I mean, seriously, is there anything better? I doubt you could name a single better dessert. You might call it heaven in a cup.

(Cooking Classy)

Andrew, sorry for the long-winded update, [Not at all! – Andrew] but let me leave you with a couple of questions:

1. I saw the pictures and videos of capsize testing using Jamie Orr’s Wayward Lass at the Wooden Boat Festival a few years back. When she was on her side, she floated high and water didn’t get into the cabin. She righted easily, it seemed. However, when turtles, she did come up, but completely flooded. With so much volume in that cabin and unsealed storage under the seats, etc., I don’t know how you would possibly add enough flotation to make her rescuable from a complete flood. Do you? it seems like the best strategy would be to make a mast float to help keep her on her side in the case of a knockdown. What do you think about this safety issue?

2. Where and how do you attach the mast traveller? I was planning to use a simple rope one. Does it need to be tended while under sail?

3. Do you have any suggestions regarding how to set up the boat to optimize its sailing performance? By this, I refer to the fact that, without a motor, I need the boat to be able to point well and sail well generally over a broad range of conditions. Any tips or rules of thumb?

Chebacco News 71 – Chris Smead’s 19’3″ Chebacco part 1

March 18, 2021 3 Replies

It has been a while since we have had a reader story – it has been worth the wait. Chris has been asking questions and posting photos of his build on Woodenboat forum for a couple of years now. This is the first part of a two part story. Enjoy. Chris Smead writes:

Hi Andrew! I started building my sheet-ply version sometime in mid-2019, with great inspiration from those who have gone before me on chebacco.com! My wife and I have four kids and live in a Virginia Beach neighborhood which doesn’t allow building projects outside. I chose the design partly because it seemed like the “most boat” I could build and store in my garage!

Dude, look at this picture (from chebacco.com). I don’t know who this is or where this photo was taken, but look how many adults and kids are just having a blast on this thing! It’s like a sailing adventure party and it fired up my imagination.

I started out laminating the spars, trying to get used to epoxy and how to work with it.

I think that’s the boom, oblong in cross-section. I used cypress. I still haven’t made the mast, which will be fir, but the rest of the spars are made and just waiting for fittings/finishing.

I hired these guys to be the crew. This picture was taken in 2019 out by Lynnhaven Bay. They look so small now. Two years makes such a big difference with kids. Don’t they look like they need a boat for adventures?

I remember laying out all these huge plywood sheets in the garage back in 2019, making straight lines and cutting with the jigsaw. You can see bulkheads and the temporary forms up against the back wall. On the ceiling is the other boat I built, an awesome 8’ Dave Gentry skin-on-frame sailing pram. Maybe it could be the tender one day? You can probably see that I have to work around lots of clutter. Our little garage serves many purposes besides boat building. It’s hard to keep it all organized, especially as the boat evolves. The curvy parts were more interesting and fiddly. This is the making of the stem pattern, bending battens over nails. This made me feel like a real boat builder, instead of just a jigsaw handler for straight lines on plywood. I made the inner and outer stems at the same time, thinking this would SURELY make them line up perfectly when it was time to attach them. (They didn’t, but it ended up working anyway.)

Here is the inner stem being laminated. It was hard to keep the layers aligned. I would have tried another system to hold everything in place if I had it to do over again. Luckily, it worked out anyway and there was plenty of wood left for the bevelling, which I messed up anyway. I needed more clamps. I still need more clamps. The thing is, it’s hard to make the inside surface smooth once all the epoxy cures because the surface is so concave and I don’t have a tool to match. A smoothish surface is needed later when fiberglassing the joint between the stem and the plywood panels on the inside, especially up near the breasthook.

Then, I got to shape the stem with a planer and a file. It’s funny, I tried to keep the bevels symmetrical as I did this, but I got off track somehow and didn’t realize it. In a later picture you may be able to discern the consequences of this mistake. If you look at the bow straight on, you mayyyyybe might see a slight asymmetry. It worked out alright, and I don’t think anyone would notice by looking at the boat now, but I will always know…

I tried to construct the hull bottom (which is flat athwartships, of course) using Payson’s method of fiberglass butt joints. Why did I make my first attempt upon the largest joint in the whole boat? You are right to ask this question. I messed it up. It’s supposed to go: Wet out fiberglass tape and ply ends with epoxy, lay out on (plastic-protected) floor, wet out new ply ends, apply fiberglass tape on top, saturate with epoxy and squeeze out bubbles with a painter’s edge.

I’m not sure if you can see in the picture, but there are a few air bubbles under the fiberglass tape (somehow). I had to perform some surgery on the big joint. Then, I had to completely remake the small forward joint. Maybe I didn’t measure the epoxy components properly? Nearest the bow, I remade the joint using some thickened epoxy between the butted edges. I also needed to make a small fillet, as the forward section of the bottom is made of Okoume 12mm, whereas the rest of the bottom is made of Doug. Fir 5/8″, which I had on hand. I know, I know, “Why would you try to make a flat panel out of different thicknesses of plywood?” Next time I will not be doing that, as it adds too much complication.

Humbled yet again, I sat in a chair for a long time thinking about what I could’ve done differently. Payson made it sound so simple in his book! Anyway, I laid some blue tape and a straight line and measured offsets to join my side panels. I used lots of epoxy this time to really saturate the tape. Yes it ended up on my floor. I also used a bit of thickened epoxy in the actual joint (I think this helped). Then, after using a roller to remove air bubbles, I lay down some saran wrap and plywood and screwed it down just to hold it together. I was nervous to look the next morning…

They actually turned out great! I then carefully laid out the strongback with a straight string. I put it on casters so I could roll it slightly out of the garage when working, since otherwise the transom is right up against the wall.

I recently learned that my neighborhood association will not allow permanently stored boats or boat trailers on the property. However, after fuming about it for a few days, I realized there would be a few advantages to storing the boat permanently in the garage, especially during hurricane season. Also, the finish might hold up longer, etc. I’m building the boat 5″ shorter than in the plans so it will fit in my garage. Trust me, I thought about all kinds of ways to build out my garage door so I could keep those 5” but didn’t come up with a reasonable solution. I briefly investigated the practice of scaling a boat’s length. It seems that boats often get stretched more successfully than “smooshed,” but we’re only talking about 2.5%, so I think it’ll be fine. Here’s hopin’!

Moving forward, while measuring things out, every 4′ becomes 47″. Things got more confusing than I thought. Here is the first bulkhead up at station 5.

I had trouble making sense of the plans regarding the transom bevels. After sitting and scratching my head for a long time, I cut some wood and made this.

I left the transom with some curve on top. This was meant to be an experiment in motorless cruising, so I didn’t see the need to cut out the motor mount yet. I know Chebacco was specifically designed to take an outboard, but I’d prefer to leave it off. I’m willing to take more time to account for tides, winds, etc., and possibly extra sail. I also realize I will need to build in safety features that don’t depend on an outboard. I am open to suggestions in this regard! My mission is to take the whole crew island-hopping in the Chesapeake Bay and Albermarle Sound over multiple days, albeit with primitive accommodations.

Here is where I noticed I had somehow messed up the bevels on the stem. See the humongous gap? I had to do some re-thinking, then some re-shaping, and later some generous gluing.

There are 7 “frames,” including the transom, which are attached to the strongback. Only Frame 4 and the transom have vertical levels specified in the table of offsets, as far as I can tell. I tried to guess at the remaining 5. After this, I lay the side planks on the frames. It took HOURS to adjust the heights of the frames to make them look right. Since the side planks are vertical, they have defined marks from the plans for placement on the frames. These fore-aft marks on the planks lined up remarkably well with the frames.

See how the bow wants to stick out of my garage? It’s a good thing I measured so carefully! I was so proud of myself. Later, when I flipped the boat, it did NOT fit because the pointy bow hit the upper rolly part of the garage door. Why hadn’t I thought about that?

I had a tough time fitting the “bilge panels” in the forward section, but got it done with some straps and clamps. Maybe I should have laminated it instead, but it wasn’t too tough. You can see I also fit the keel pieces! The centerboard case is in there too. Trust me. This is a messy job, but the end product is quite satisfying!

I spent some time on the inside fillets of thickened epoxy but decided to leave the fiberglass tape for when the boat was right-side up. I did fit the sheer stringer. Maybe you call it the clamp? Here is the ugliest part of it, where I scarphed in a piece and tried to make it look like it belonged there. Luckily, this piece will be under the deck behind the cockpit coaming and will not be visible in the finished boat. Here is the test with the centerboard pivoting in its case. I had to do some sanding with a long stick to smooth out the epoxy on the inside of the case. Once I got it working, I shaped and ballasted the board. I used some lead shot I found combined with some ingots I ordered online. I painted it with some red leftover Rustoleum hardware store paint. I mean, only fish will see it, right?

I spent some time fairing the hull. I used West System fairing filler with some silica thickener. By this point, it was much harder to see the asymmetry between the topsides at the stem!

Oh, and I started messing with an offcut from one of the spars to see if it could become the Jonesport cleat. I really like the look of the Chebacco bow, so I wanted to get this piece right!

Chebacco News 64 – The Coulson Build

May 31, 2019 4 Replies

Over a year ago, Canadians Shelley and Jerry sent me some photos of their sheet ply build – and a great looking marine grade aluminium rudder. I am looking forward to hear how it works. Jerry has built over 40 boats and this build shows his skills.

Great news just today:

Hi Andrew. We just put her in the water. We are in midst of setting the sails properly and adding fittings etc. We are hoping to go sailing this weekend. Thank you for your interest. I’ll send a picture. Take care. Shelley.

UPDATE July 2019: She is for sale, the for sale pages.

Chebacco News 63 – Octagonal or round mast?

May 20, 2019 2 Replies

When I built the birdsmouth mast for Khaos, my Chebacco 25, I liked the look of the eight sided stick. So I rounded the corners and varnished the beautiful octagonal showpiece.

But that turned out to be the wrong thing to do, The varnish didn’t like protecting the corners and after a time cracked and let in water. After some more time the water got into the timber (Queensland hoop pine) and the swelling caused cracks to form.

So, over the last few weeks I have removed the mast from the tabernacle and put it on saw horses outside my shed. Epoxy filled the cracks. Planing took 8 sided to 16 sided. More planing took 16 sided to 32 sided. At this point I made up a sanding contraption with an old drill, threaded rod and two plastic wheels.

This contraption is the third version I made, I discovered that the rubber tyre was important for grip and that the tyre must be a larger diameter than the mast. None of the websites I visited mentioned this fact, but it is critical, the friction on the driving tyres must be more than the friction on the mast itself, otherwise you end up sanding the driving tyres not the mast. For geometry reasons the larger diameter tyre has more contact area than the smaller diameter mast and this results in more friction between the tyre and the inside of the (inside out) sanding belt.

I started with 80 grit and ended with 220 grit.

I held the other end of the rod with a bit of steel with a hole in it. Simple.

This turned out to be the only way to practically sand this mast. 5″ x 20′ turns out to be a lot of sanding and completely impractical for hand sanding. Even then it took me two weeks of sanding sessions (limited by my stamina)

The round mast looks good too.

Andrew

Chebacco News 62 – 11 years and counting, a cedar strip build

April 29, 2019 2 Replies

Received from Dennis Gamble recently:

I live in Marshfield, Wisconsin, and have been building my Chebacco for about 11 years now. After completing a Bolger Gypsy back in 2004, I decided I needed something a bit larger. I did not enjoy the sanding of epoxy required for the tack and tape method, so I decided to build my boat using sawn frames and chine logs instead.

I first lofted the boat full size in my basement on ¼ inch gypsum board. I then built the frames, inner stem, centerboard and case. The frames and stem are of douglas fir. The next step would have been the strong back, but I didn’t have a large enough space to set the boat up at my previous residence. So the frames and centerboard went up into the garage rafters for a couple of years until I moved into my current home.

I have a double garage now, about 22 feet deep. The strongback went up in the right side stall, and the boat has lived there ever since. My hull is constructed of 3 layers. The first 2 layers are ¼ inch by 1.5 inch cedar strips laid on a diagonal at 90 degrees. The outer layer is 1/8 inch meranti plywood. The hull is covered on the outside with 4 oz fiberglass cloth set in epoxy. I will not be fiberglassing the inside. In retrospect I would probably have used plywood for the hull, as this is a fairly labor intensive method of construction. Also, my hull is not as fair as it could be. This did not become apparent until after I had glassed, painted and flipped it onto it’s trailer. I will repaint with a flat finish rather than re-glass. I have been using ½ inch MDO for the cockpit, deck and cabin construction. All exterior horizontal surfaces will have a layer of 4 ounce fiberglass cloth set in epoxy. I am using thickened epoxy for exterior glue joints. I have been using PL Premium construction adhesive for most interior joinery.

Progress has been slow but steady. I added a heater to my garage a few years ago, which has allowed me to work through the Winter. I try to work on the boat a little every day, but probably average only 5 hours a week. At my current pace, I’m probably 3 to 4 years away from launching. I haven’t taken many construction pictures, and have lost track of some of the earlier shots, but here are some newer shots. More shots at https://saildubay.club/boat-building-project/

Chebacco News 61 – Mudlark, the other Chebacco 25

February 28, 2019 Leave a reply

I received an exciting email from Simon Jones in South Australia. If you have read all the newsletters you may remember Simon started a Chebacco 25 back in newsletter 26 (1999). The hull got built but the project got put on hold for many years. Simon tells me the covers are coming off and he hopes to have Mudlark in the water next summer (southern hemisphere).

I’ll let Simon tell the story:

“Call me dumb or stubborn, I knew I only had one big boat in me but a multitude of ideas and wishes that I had to incorporate into my build.

I loved the basic lines of the C25, I didn’t like a lot of other things, the cabin was too low, the centreboard was a huge lump in the way, the rudder was too small and not on the stern, the cat rig was too cumbersome and inflexible.

I wrote to Bolger asking for advice and any thoughts. I received a very terse reply to the effect that any deviation was an abomination and I was on my own.

Changes.

Raised the freeboard one plank to allow for sitting headroom over water ballast tanks under quarter berths.

Moved to ketch rig with adjustable bowsprit and stern hung rudder.

Moved from centreboard to leeboards.

Extended cabin top and recambered.

Installed watertight bulkheads fore and aft.

Reduced depth of keelson to allow for more stable grounding.

Rearranged interior to sleep four with central galley.

Cheers Simon.”

I have suggested a meeting of the only two Chebacco 25’s at Goolwa wooden boat festival in two years time – are there any other Chebacco owners in Australia who might want to join us?

Chebacco News 59 – Pete Greenfield’s Outdoor Boat

December 8, 2017 5 Replies

Pete Greenfield is the editor of Watercraft Magazine in the UK (watercraft-magazine.com) a magazine dedicated to small home build boats. In 2009 he recycled the moulds from a lapstrake Chebacco that Connie Mense had used to build her beautiful “Argo”. See the resources section under websites for photos of Argo. Peter wrote about his journey to build his own Chebacco (actually he is still writing about his journey, like so many boatbuilding journeys it is a long one!) in Watercraft Magazine and he has graciously given me permission to reproduce some of his articles.

This is the first one he wrote in the November/December 2009 edition:

Building the OUTDOOR BOAT

by Pete Greenfield

Underneath the spreading chestnut tree, the editor has recycled Connie Mense’s moulds to build his own Chebacco Boat. And the green-ness of the project doesn’t stop there. With photographs by the author and the resident twitcher.

Why do birds suddenly appear every time I go near the boat frame in our garden? The cat has only to purr from the depths of a duvet in a distant bedroom and they take flight instantly. But when I peel back the polytarp from the boatbuilding frame, every tit in Cornwall turns up to perch on it. I never liked that Hitchcock film. Worse, they’ve all been devouring the autumn’s raspberries, so my boatbuilding frame is beginning to look like a Crime Scene and – I kid you not here – a hungry-looking lesser-spotted woodpecker has also taken to visiting and I swear he has his onyx eye on my lining-off battens.

I’m quietly proud of my lining-off battens, not least because in the past, I’ve had problems with battens. Last time, they were fairing battens. A fairing batten is a length of small section timber which you lay across the erected inverted mould frames to check that they are …er… fair, meaning that you have set up the moulds so accurately that the batten takes up a suent curve, without humps or hollows, as it drapes across them. Needless to say, the fairing batten should not be so thin that it sags between moulds or so thick that it will not bend over them without resort to brute force. Equally, there should be no imperfections in the fairing batten – knots, kinks or badly made joints – which cause deflections, making it harder to check whether your moulds are really fair. Or, in the case of my previous ferro boat, really not.

You do not need lining-off battens for the monocoque hulls of ferro boats. You do need them when building a clinker planked wooden boat because they delineate the edges of the planks which are a major factor in the visual appeal of the boat. These clinker planks might look to the untutored eye as if they have straight parallel sides and are all of equal width but as Water Craft alumni will be aware, in reality such planks are frequently banana-shaped, sometimes S-shaped and the beamier the boat, the more curvaceous they need to be. Further, the illusion that the planks of the topsides are identical is created when the boatbuilder determines the shape of the garboard, the plank nearest the keel, which may well need to be a convoluted S-shaped banana with extra-wide ends…

But enough of GM crops… take it from me that when a shapely clinker hull is lined off so that the lie of every single plank from garboard to sheerstrake looks just right, it’s a work of art as much as craft and the tangible testament to the hand and eye of a real boatbuilder. Which is why, rather than mess it up myself, I decided to use the lining-off marks Connie had left on her moulds. But I still needed a full set of lining-off battens, all long enough to wrap around the hull from stem to stern, all knot- and kink-free. Fat chance of finding suitable timber in west Cornwall, I grumbled and went to the nearest builders’ merchant with little hope and less expectation.

Alas, dear reader, that I should have been so unjust! There at the Culdrose branch of the Travis Perkins chain, beyond the inevitable breeze blocks, pea gravel, drains and decking, huddled in the crepuscular cathedral of the timber shed, I found long lengths of straight grained and generally knot-free red pine in various sizes including a nominal 38 x 16mm, which they supply ‘Planed All Round’ at 34 x 11mm. Which is how, me buckos, a national disseminator of what Betjeman called ‘bungaloid growth’ came to determine that the lands – the overlaps of the clinker planking – on our Chebacco boat will be precisely 1 5/1 6″ (34mm) wide.

Unfortunately, however, the longest pieces TP could supply were around 15’6″ (4.8m) which meant proper joints would be needed; scarf joints which would not create kinks when the battens were bent to the hull curve. In the past, I’ve had problems with scarf joints.

The scarf joint, Grasshopper, is the boatbuilding joint. When one long length of timber must be made from two short ones, the shipwright cuts identical opposed tapers which mate together. Long tapers are required to get the largest possible ‘faying surfaces’ – the faces of the timber which will be glued together – which means the scarf needs to be at least eight times as long as the thickness of the timber being joined.

In the past, I would try to cut the taper with a tenon saw, the saw would invariably veer off-square and I would then need to plane vigorously to get a uniform incline, all too often creating in the process a speed-bump halfway along the taper. Planing down the speed-bump, I would start to get break-out at the feather edge. I would also start to get rather irritated.

So, Grasshopper, reach not for your western saw. Take up instead your Gyokucho Ryoba Kommane – yes, I had noticed that this running metaphor is crossing cultures, thank you – which has a 12″ (0.3m) double-edged blade, with rip teeth on one edge and crosscut teeth on the other. This gives the unique combination of a saw blade short enough to be used with some precision yet with rip teeth which are much better suited to a shallow diagonal cut virtually along the grain. Do not – at first; you will later – saw to the line; cut a little shy to allow for a couple of passes of the plane.

My other problem with scarfs used to come when I glued the two halves of the scarf together: all too often, as clamping pressure was applied the tapers would slide apart and sometimes go off at a tangent in the process.

It was under the tutelage of Mr D Phillips at Falmouth Marine School that I learned to do scarfs properly. First off, you need a base to support the scarf while you glue it: a clean plank, as long as you’ve got, with a nice straight edge. About midway along the plank, square across two lines to show the extent of the scarf joint, then wrap this area in cling-film to prevent the job sticking to the base.

For quick jobs outdoors, I have found Gorilla Glue easy and forgiving to use, tolerant of low temperatures, quickly cleaned up and very strong once set. It’s a polyurethane, so no mixing is needed and it’s not only tolerant of damp timber, it likes it. So much so that you are advised to spread the Gorilla Glue on one of the faying surfaces – now you do remember what a faying surface is, don’t you children? — and paint the other one with water. The wetter you make this face the more the Gorilla Glue will foam up as it sets; the foam fills crevices but does not act as a bonding agent on sloppy joinery.

So, my method when gluing scarf joints is to first clamp the piece of timber with the lower part of the scarf to the base, aligning it with the marked lines and the edge of the base and positioning the clamp well away from the action. Apply the Gorilla Glue to the taper. Wet the matching taper on the other half of the joint and lower this second piece of timber into place, again lining it up with the joint lines and the base edge and securing it firmly in place with a clamp well away from the joint. And it’s only when I’m sure the two pieces of timber are correctly aligned and firmly held in place that I wrap the topside of the scarf joint in more cling-film, add a scrap of ply on top to spread pressure and then clamp up the joint firmly. This way, I suffer from none of those old kinks and slippage; an important consideration at my age, Grasshopper.

Chebacco News 56 – Chebacco 25

December 10, 2015 7 Replies

Chebacco.com has a new webmaster and a new look

Hi, I’m Andrew Yen. I live in Victoria, Australia and I am passionate about Phil Bolger’s Chebacco boats. Thanks Richard for all the time and effort (and money) you have put into the site over the years since taking over from Bill. Now it is my turn to help Chebacco owners and builders to share their experiences on the web. If you have stories to tell, email me <insert my first name>@chebacco.com. If you wish to support the site financially please use the “donate” button at the bottom of each page.

Chebacco 25 launched

I decided to build a Chebacco 25, Easter 2010, despite there being no other examples to follow and no designer to ask questions of. The design is described in Boats with and Open Mind (see the resources page). It is glued plywood lapstrake, 25’4″ long by 8’2″ beam. About as large as you would want to trailer behind a SUV. The designed displacement is 2,200 pounds (1 tonne) and she has a split rig a little larger than the 20′ Chebacco. The cockpit is huge, at 12′ long and the cabin is somewhat larger than the 20’ers cuddy. The outboard is located centrally in a transom cut out and I have a 15hp Johnson that so far has pushed her just over hull speed flat out. With the right conditions she might plane one day (Phil claimed a Chebacco 25 would plane with 15hp, but maybe he was overly ambitious).

I changed the cabin from a raised deck to a conventional trunk after struggling for weeks to get the plank lines and sheer line to “look right” on the raised deck cabin. I also borrowed the #540RD (Raised Deck Chebacco) rudder design and adapted the rig design from Bolger’s Martha Jane. The birdsmouth mast is hinged in a tabernacle and the lower section is counterweighted with lead shot. This means one handed 10 second mast stepping. That is quicker and easier than anything else you see at the boat ramp.

I sealed the cockpit footwell from the interior of the hull and the planking stock ended up 15mm rather than 1/2″ (12.4mm). Otherwise I tried to be as faithful to the original drawings as I could.

It took 4 years of evenings to build, over 40 litres of epoxy and lots of sheets of marine plywood – but she looks stunning. She is called KHAOS, and was launched 27/7/2014 on Albert Park Lake, close to Melbourne CBD. I suspect that this is one of the largest yachts to ever sail on this little lake and if I had asked for permission first I would have been told no!

Start by building the moulds

Then add carefully measured and spiled planks

The plank lines needed to be determined individually

The centreboard case is so large it required a winch to insert it into the hull

The outer stem was made from a spotted gum railway sleeper

the balanced rudder backbone is stainless rod – no welds.

The rudder shaft bearing is graphite filled epoxy

The cockpit footwell is sealed – so no water can get inside the hull

Sailing on Albert Park Lake – close to Melbourne CBD

As far as I know this is the first and only example of the Bolger Chebacco 25 in existence. Another hull, based on the Chebacco 25 design, was started in South Australia 18 years ago but, for personal reasons, is not yet completed.

I cannot speculate as to why no one else has taken up the challenge. Sure she is a bigger boat than the 20’er, so it has been more work to build (maybe a lot more work). But she is not much heavier when on the trailer and is easily towed by my SUV. The biggest issue with the size is the required space to store and manoeuvre it on the trailer. There is no turning space on my property so I have to reverse it from about 800m up the street and then up my driveway in order to park it.

But size has its advantages, I have comfortably sailed with 6 or more on board and have slept 3 in the cabin on one occasion. A planned modification (removing a sail locker that is taking up valuable space and not being used) will give me 4 berths in the cabin.

Chebacco News 55

November 10, 2011 Leave a reply

2011 “World” Pudleduck – Richard Spelling

Sorry, it has been quite a while since I have updated this site. You see I kind of get obsessed with things. I was building a house for me and the kids to live in. Then a tornado came and blew it away. So then I was re-building a house to live in…

other things and picking up the pieces. (both literally and figuratively)

The only time I have had the boat out was a couple of weekenders to Eufala, which I write about in this issue.

Other than that, my current obsession is the 3D printer I built.

It’s a Self Replicating Rapid Prototype Machine, a 3D Cartesian Robot using Fused Deposition Modeling. I call it “Bob”. To the right is the faucet handle I printed to replace the one that was busted by the tornado when it scraped the well house off to ground level.

Also, my tractor had the good graces to die right in front of the shop, and to wait till after I used it to push the remanents of the old house down… so I had to fix my tractor so I could get the boat out… 🙂

Oh, yeah, and I’m Divorcing the wife I re-married. My “re-wife” as a friend calls her. I think I have learned my lesson this time.

Only misshap on the trip this year was that the exit off the turnpike was right after the toll booths. I mean like 25 feet. I was in the far left lane so I could use my pike pass, and there was NO WAY I could have made that turn. Oh, well. GPS sent me on a different route this year than it did last year. I have ignored it before to my peril, so I followed it’s instructions this time. Last year I almost blew a trailer tire. The second one, both from Pep Boys. Granted I am running them right at the load limit. I was able to put on the spare and limp to a tire place, who had real load rated trailer tires to sell me, so that worked out.

Well, also when I was getting the boat ready, I discovered the motor wasn’t pumping water out the tell-tale. I took it apart and just flipped over the impeller wheel for now, after greasing it up with a fancy teflon based greese. The fun part was the six hours I spent trying to get the bleeping lower end to fit back on. I finally gave up and went to bed. In the morning I got up, spun the shifter lever around 180 degrees, and it it went on like it was designed that way. Go figure. 1IMAG0157

The messabout was held again at the Monies place at lake Eufuala. Better organized this year, with the tents in the back and even lined up. The Monies provide free food, but myself and others chip in cash to cover their expenses. Hopefully they do not take too much of a hit on the food costs.

I could barely squeeze the truck and trailer through all the cars, and someone told me the ramp was un-usable, so I had to go to the state park down the road and launch. I walked up from the beach, where there was a LOT of boats, on friday night, just after dark. Beached the boat way on the end by a Micro that looked vaguely familiar.

Walked up to the Monies place and there were people on a loudspeaker. How weird. Jim Michalak and two others were speaking about plywood… and it looked like they were selling raffle tickets. And t-shirts. Unfortuantly, these were WHITE t-shires. I have no businsess owning white t-shirts… They finished talking, and we all went to get food. Talked to Jim and responded that I had built a 3d-printer when he asked what was up… All the old friends were there, except Chuck

Visiting with friends, Mia (ex-step grand daughter) make a new friend or two, I check email on my smartphone.

This was the second annual “world” puddle duck gathering. Very reasonably held in October when it’s not so bleeping hot outside. Puddle Ducks are small square boat, a racing “class” boat, but interestingly only the hull lines are fixed, everything else is alowed to be changed. This basically lets you play designer as well as race your boat. Very Interesting, but not interesting enough for me to want to make one and race… lol

Next day they had various events, which I ignored. Funny how I can drive hundreds of mile to meet friends and boat builders, then be unsociable… 🙂 I went sailing back to the ramp to pick up the things I had printed to show Jim et. al. Water level was much lower this year than last, with the dangerous hidden stumps at least sticking out of the water this year! Interesting that they were all about the same height. I assume oxygen lets them rot above the water line. I tried to avoid the stumps and the racing course.

Lots of boats.

Kids swiming. Daughter playing disaffected teenager.

***

Chebacco Bluster – Randy Wheating

Hi Richard, here is a small article…

Bees on the High Seas

Well known Chebaccoist Jamie Orr and our friend and fellow small boat enthusiast Curtis joined me aboard Chebacco Bluster for a fall sailing day in October 2008. We launched at the picturesque Gibsons Landing Marina. Gibsons is a small town a short ferry ride away from West Vancouver, British Columbia and famous as the setting for the long running CBC television series “The Beachcombers”.

With had no particular plan beyond getting out on the water, we spent a leisurely morning tacking north against the ebbing tide of Shoal Channel . It was one of those lovely sunny fall days with just a hint of chill and contentment in the air. Just as we were breaking out the lunch Curtis noticed what appeared to be a bees’ nest inside the cabin. I took a peek and sure enough it was. When we were preparing to launch I just tossed our cooler and bags into the cabin with out really looking inside. The bees must have moved in while Bluster was stored in the driveway under tarps. I was pretty sure the nest was abandoned but thought in prudent to wait until we were docked before and closer inspection. Nowhere to run on a twenty foot sailboat a couple kms away from shore!

Bravely we continued on until reaching the New Brighton public dock on Gambier Island. We tied up and went ashore to visit the quaint general store there. Back aboard we motored back to Gibsons Landing where we secured a berth in the marina for Bluster. My last duty was to bundle up and crawl forward in the cabin to knock the bees’ nest into a paper bag. As we hoped, no live bees. I did notice Curtis was well back but had his video camera ready just in case! Thanks for a great sailing day Jamie and Curtis.

Randy Wheating

Chebacco Bluster

***

Rigging – Skip Pahl

Hi Richard, Happy to send you some stuff. Here’s s shot of her on the day I finished the rigging.

***

Chebacco 25 Downunder – Andrew Yen

Hi Richard,

I built my first rowboat on a dare from my pre-school aged son (see: http://www.boatbuilder.com.au/images/stories/mag/smiggy.pdf ). Then my second son wanted to out-do his brother so I built him a sail-boat (a Bolger Cartopper). By then the boat building and the sailing bugs had bitten!

My dilemma was that I have three young adventurous children and my largest boat was an older 15′ trailer-sailer. I needed a bigger boat, a versatile trailerable boat with a shallow draft, occasional accommodation for five, easy to sail, good looking – and I wanted to build it. Over years of study I kept coming back to the Chebacco design. I like the look of the lapstrake version. But I had reservations about 20′. While much bigger than my current trailer-sailer I wondered if a growing family of five would find it too cramped.

This logically lead to a serious study of the Chebacco 25.

There were a number of down sides:

As far as I can tell only one has been built and that one was highly modified.
Phil wasn’t going to be around to give advice.
The design had not grown and progressed like the 20′ version has over the years.

But on the up side it was light for its size, small enough to tow behind my 4WD but with generous cockpit accommodation. And it was attractive. It has that Chebacco lineage.

Six months ago I started using the offsets in Boats With An Open Mind to mark and cut out the moulds from some scrap ply I had. Cost so far $0.

Then I made a building frame from left over timber from a construction project my company was working on. Cost so far $0.

Then I put it all together and it started looking like it might be a boat some day. Cost so far $0.

I had a decision to make – my investment so far had been about two months of evenings in the shed. This is the point where I was going to have to spend money. Susanne Altenburger wrote to me offering plans and building details as I was pondering whether to commit or not. She suggested that I could adapt the lessons learnt on the Chebacco 20 to the Chebacco 25 and gave me some clues as to how.

That did it. I realized that I had been committed since I first saw the design in BWAOM.

I have now scarfed the bottom and fitted a modified sternpost/rudder-stock housing. This rudder stock housing will accommodate a version of the Chebacco RD’s balanced rudder design (see Ben Ho’s description on Chebacco.com).

Iain Oughtred’s book on plywood clinker construction has been very helpful as I work out how all the part will fit together. Attached are some photos. Sorry that it is hard to stand back and take good photos when there is the frame of a 25′ boat in you 28′ shed! I will keep you updated as I make progress, or you can follow progress on a website my mate has started putting together http://sites.google.com/site/warrandytewoodenboat/Warrandyte-Wooden-Boats

Regards,

Andrew Yen Victoria, Australia

***

MY CHEBACCO AFTER LAUNCHING – Unknown author

(The hole in the bottom of the boat)

Launching went well and the mast was easily stepped using the mast slot. She floated well and looked good.

Then, WATER! But not where I wanted it: When my friend Pete and I sailed her away from the dock for the first time, water started coming up the rudder shaft and making its way down toward the cockpit. We didn’t notice it at first because we were enjoying the quiet sail and looking at the sail to check the shape and so on.

When I built the after-deck/rudder post support I epoxied one side but left the other side open so that I could check what I was doing when I installed the rudder shaft. I had drilled a hole to accommodate a two inch post as shown in the plans and built the rudder post box support to that size shaft but obtained and used a solid brass shaft a little more than one inch in diameter. Then when I installed the last side of the rudder post box I was not careful in sealing it- I figured I would like access to check on things. So while the rudder shaft surroundings were rugged they were not waterproof.

Pete and I removed the mizzen mast and partner, then the “after deck” and removed the side of the after deck support. I applied 5200 caulking as much as possible and had trouble free sailing after that. Until…

I borrowed a 5 hp outboard and mounted it so I could see if it would be enough to push the Chebacco against the wind and tide. Alas, the weight of the motor lowered the waterline at the rudder post hole and the forward motion of the boat combined to bring water aboard at such a rate that I had to pump continually while we motored back to the mooring. So the 5200 didn’t solve the problem completely. I was surprised at the amount of water that came aboard.

When Hurricane Ophelia threatened heavy rain I chose to haul the boat rather than worry about the rain settling the boat low enough to bring more water aboard.

Back on land I removed, again, the mizzen partner, the after deck, and pried off the still removable side. I know water molecules are very small, and there are lots of them (says Avogadro), but I was amazed by the flow of water into the boat.

I removed the rudder completely and studied the box that enclosed the rudder post. There were no obvious voids.

I temporarily stuck a piece of thin transparent acrylic over the rudder post box with some sticky window caulking stuff and covered the hole in the bottom of the boat making, in effect, a small but columnar aquarium. When I filled it with water the water level quickly dropped, leaking around the caulking.

I found a thicker piece of Plexiglas, bought a tube of 100% silicone caulking and scraped the gunk from experiment number one. I drilled six holes to screw the plexi to the frame, applied the silicone as carefully as possible and attached the plastic with screws. I waited overnight. I dumped more water into my tall thin aquarium-like rudder box and it seemed that I was in business. So it’s winter now in New England and in the Spring I’ll do another check. My current plan is to leave the Plexiglass in place since the rest of the after deck support is very strong. It is very ugly to look at because I used 5200 while the boat was still in the water and I got it all over the place. Also my woodworking skills are workboat level at best. This whole area is covered, though, by the afterdeck.

Moral: seal that rudder box well.

OLYMPUS DIGITAL CAMERA

She was in the water for only about three weeks and I never fully tested her but I had a list of things to attend to. (I used the few days after launching to make a list of adjustments.) She sails nicely in next to zero wind but I have not yet sailed her with a reef. She has a neutral helm in light wind but rounded up quickly in small gusts. I don’t know how much weather helm she’ll have and won’t know till next spring because I hauled her two days before hurricane Ophelia was scheduled to perhaps dump rain on us.

***

Notes on making the mast for my Chebacco. – another unknown author

I’m sure many will find fault with what I’ve done but I had a good time with this project.

I needed stock for a nineteen foot mast, four inches around. Some others have had access to good stock from old buildings (or perhaps even trees!) but I did not.

I probably should have explored using construction staging planks but it was too late, I had already purchased clear pine at the suggestion of the guy who was helping me with the project. I sanded bevels for scarfs, imperfectly, (I had considered using a plane but thought I could sand them better- now I’m not so sure). I glued the scarfs with epoxy to get enough length – I made six long planks out of twelve shorter ones. I then epoxied three sets of two, and finally epoxied the pairs together to make the full blank.

I had access to a very large floor-model power planer so we planed the blank square. It looked great!

It was quite straight and smooth.

The plans showed a taper for the last few feet of the mast so marks were made on all sides of the blank. Then a straight edge was used to mark the taper on all sides. I was a little afraid to use a power planer at first, so a hand-held plane was used to remove stock on the first side. This was a real workout, even with a sharp tool, but it was quite satisfying. However, I tried a hand held power planer on the remaining sides and found that I could control the removal quite well and the results were probably better with the power tool. Once the taper was cut on all sides, both ends, the stock was ready for 8 siding.

The jig for 8 siding is easy to make. I cut a stick about an inch square from a scrap of 2×4. (I wanted enough thickness to hold the pencils without wobbling). I drilled holes for nails positioned at the outer edge of the mast blank. The holes were slightly smaller than the nails to grip them tightly. I then divided the distance between the nails (distance between the sides of the mast) into thirds and drilled holes to grip two pencils 1/3 and 2/3 of the distance between the nail holes (nails not inserted yet). I hammered in the nails which extend down the sides of the mast blank. I pushed the pencils into the jig so that the tips showed enough to make marks.

The jig moves along the blank, and when the blank tapers toward the tip the jig slides along at an angle and continues to make nice even divisions.

The hand held power plane was again used to remove the four corners down to the marks. Again I found the tool quite easy to control and I was able to get reasonably close to the marks. I was very happy because it looked like a mast (to me anyway). I decided I liked the hard sided look so I am not going to 16 sides and round. I’m just going to soften the hard edges leave it as is.

Chebacco Sailboats – Designed by Phil Bolger