Building the CoPogy 18

[AJZimm]

Having always been a self-propelled kind of guy, or at least self-propelled when the wind wasn’t blowing, having designed and built my own sail and oar boat, and having held the belief that age is just a number, I figured I’d always be a sail and oar guy.

However, as Robbie Burns sagely noted, “The best-laid schemes o' mice an 'men gang aft agley”, or sh** happens. After developing periodic atrial fibrillation (afib in medical shorthand), the cardiologist advised me that going out and rowing for 8+ hours a day for weeks on end during a cruise is no longer a recipe for growing old(er) gracefully. I caved in and bought a 2½ HP outboard to propel Fire-Drake, my sail and oar boat, in the calms, but it’s not a congenial match.

After much pondering and brooding, I finally came to the conclusion, that if I want to keep getting out there on extended voyages along our wonderful BC coast, I really should do it in a different boat, a motorsailer of some kind. I still want to sail when the wind serves, but the boat should be happy motoring all day in the calm and/or the rain that we get up the coast. The rain also means that if I could find something with a small cabin, so much the better. I could have gone out and bought a used small production plastic cruiser, but I viewed this is an excuse to build another boat.
As it would mostly be me cruising solo, it didn’t need to be a big boat. I didn’t want the expense of a boat that had to be kept in the water, so: trailerable. A third constraint is the size of my garage/boatbuilding shop. I had thought that Fire-Drake, at 18’ long and 5’4” wide, was the biggest boat I could build in the shop. After re-examining the shop, moving things around, and offloading one large power tool I didn’t use much, I figured I could build a boat of about the same length, but a little wider.

All these considerations led me to Tad Robert’s Pogy 17 design, which is, as he puts it, “a minimum coastal cruiser for one or two people”. When I contacted him and said I was ready to order the plans, he told me that the detailed plans had never been developed, as nobody had built one, and essentially that now, several years later, he would come up with a slightly different solution for the same mission. What he proposed sounded like an even better fit for what I had in mind and, to cut to the chase, the result is the “CoPogy 18”, which I’ve started to build.

Principal hull dimensions: length: 18’1½”, waterline: about 17’3”, beam: 6’5 ½”, draft: 9”

3D Rendering
CP18view01.jpg

Sail plan/profile view, (with colour added, crudely, by me)
Profile veiw coloured.jpg

[Max F]

A nice little cruiser Alex. I´m looking forward to your build thread.

[AJZimm]

A nice little cruiser Alex. I´m looking forward to your build thread.

Thanks Max. I'll post some pictures of the first steps once I have them uploaded from my phone and sorted.

[rgthom]

Neat little boat. I've been thinking of Welsford's Long Steps as next boat for a similar use, but this is intriguing with more hard cabin. There's sitting room to look out those windows? Are you going to use the 2.5 hp motor and where does it go?

Rick

[Yeadon]

Same motor as before or do you have an electric solution in mind?

[WI-Tom]

Alex, I'm glad to see how you're keepin' on keepin' on despite the afib. Looks like a smart choice of designs there--I'll watch your progress with great interest. I could easily see something like this in my future at some point, too. I've already progressed (devolved?) to the point where I now bring along a chair on my cruises, and it's all downhill from there!

Good luck with the build. I'll be especially interested in your feedback on how roomy/non-roomy the cabin is--for me, about 38" of headroom above the seat is the minimum I could tolerate.

Tom

[timo4352]

Interesting.
I'll be following too.
Enjoy the build.

[cstevens]

Fantastic! I love little motorsailers and Tad’s designs in particular. Sorry to hear about the afib Alex, but I’ll enjoy following this build.

[Rich Jones]

I'll be following with interest.

[AJZimm]

There's sitting room to look out those windows? Are you going to use the 2.5 hp motor and where does it go?

Rick

Same motor as before or do you have an electric solution in mind?

There definitely will be sitting room to look out the windows. At least 48 inches, I think.

Probably need a bigger motor. The 2 1/2 would likely push it along just fine below hull speed in a flat calm but I expect it would be working hard to do so and get terrible mileage while it's at it. A 4 or even 6 HP would likely run at part throttle most of the time, improving mileage, but still have reserve to cope with a string headwind, say, should I ever need it. Also, you have to go to those sizes to get an attached alternator.

I thought about electric, but not for very long. For the extended, multi-week trips beyond the each of shore power I have in mind, I couldn't pack enough solar panels on the boat to power the motor for long enough. I have done some rough calculations, and, using reasonable assumptions, I would need nearly 7 square meters (~730 ft2) of solar panel to recharge batteries in one day, to make up for the energy used for a 2 1/2 HP equivalent electric motor, running at only 60% load. Not gonna happen. I could carry a gas-powered generator to recharge the batteries, but that seems to me to just add another inefficiency into the system, so why not just go with the OB in the first place? Besides, in a whole season, I doubt I would use much more than the equivalent of a tank of gas for the tow vehicle.

[timo4352]

With the amount of head room in the cabin would an inside (seated) helm be possible?
That would be great for foul weather.

[AJZimm]

Tad’s a busy guy, so I’m getting the drawings in stages as he works through the details. The hull dimensions are fixed, so I’m starting with that. Hull construction is marine ply; 9mm for the bottom and lower strakes, 6 mm for the topside and raised deck strakes. Tad has kindly provided a strake layout drawing, so no lofting is required.

Given my limited shop floor space, and that the rainy season is pretty much upon us here, I’m making the hull strakes and also plan to make the bulkheads before I set up the strongback.

First order of business is scarfing together 3 sheets of ply for stock long enough to cut out the strakes from. I have to do this three times. I’ve scarfed lots of smaller planks and narrower pieces of lumber, but never a full 4’ sheet of ply, so I approached it with some trepidation. I considered all sorts of jigs, but in the end decided just to use planes.

I did have to build a take-apart table for cutting the scarfs, to be disassembled between sets of cut scarfs, while I glued them up into long panels


Joubert Occoume, BS 1088


First scarf (8:1) cut with hand planes, just being cautious until I knew what I was up against. Used hand power planer on subsequent scarfs.


Dry fit, with pencilled reference lines and a couple of finishing nails, sans heads, for registration pins

[AJZimm]

With the amount of head room in the cabin would an inside (seated) helm be possible?
That would be great for foul weather.

I think so. That is what I am planning on doing. Haven't figured out placement, construction details or how to connect steering and motor controls yet - that will all be easier to do once I have the hull built, I think.

[rgthom]

Probably need a bigger motor. The 2 1/2 would likely push it along just fine below hull speed in a flat calm but I expect it would be working hard to do so and get terrible mileage while it's at it. A 4 or even 6 HP would likely run at part throttle most of the time, improving mileage, but still have reserve to cope with a string headwind, say, should I ever need it. Also, you have to go to those sizes to get an attached alternator.

I know very little about motors, but was pleasantly surprised to find that a 220 W electric outboard drives my 18' skiff to around hull speed (4.3 kts) in calm. I would have thought 2.5 hp more than enough, but bigger is more insurance. Does it go on the transom (not in a well)?

[AJZimm]

I know very little about motors, but was pleasantly surprised to find that a 220 W electric outboard drives my 18' skiff to around hull speed (4.3 kts) in calm. I would have thought 2.5 hp more than enough, but bigger is more insurance. Does it go on the transom (not in a well)?

220 Watts is almost a third of a horsepower, so, if your skiff is light enough, I can believe 4.3 knots. My gasoline 2.5 HP OB only develops its full power pretty much at full throttle. Running at that speed all the time would definitely shorten the life. So the useful HP for all-day running at part throttle is likely only around 1 HP, maybe less. It's hard to say for sure as I have never been able to find a power curve for these little motors. I find that about 1/4 - 1/3 throttle pushes Fire-Drake, a displacement hull, when loaded to an all-up weight of about 850 lbs, along at 3-4 knots. It takes the rest of the throttle to get it up to hull speed, which is about 5 1/2 knots.

Electric motors on the other hand usually have a much flatter torque and power curve, so a lot more of the power is usable across a broader range of speeds.

The outboard on the CoPogy 18 will go in a well.

[rgthom]

Just looked up the Pogy 17 on Tad's site, it's a more substantial boat than I thought:

• Displacement: 1,500 lbs lightship, 2400 lbs cruising
• Sail Area: 142 sq.ft.
• Ballast: Steel centerboard of 110 lbs

That's much heavier than my rowing skiff. Is the CoPogy the same?

[Woxbox]

Nice project. I'll be following.

[epoxyboy]

I know very little about motors, but was pleasantly surprised to find that a 220 W electric outboard drives my 18' skiff to around hull speed (4.3 kts) in calm. I would have thought 2.5 hp more than enough, but bigger is more insurance. Does it go on the transom (not in a well)?

I had a 4.5hp outboard on a Welsford Pathfinder of very similar dimensions. Half throttle or less for hull speed in calm conditions, and there were only a couple of times when a little more might have been good, just to avoid running a two stroke at WOT. If there is a barge pusher prop option, that would be worth going for.

Pete

[Dave Lesser]

Very nice, Alex. Planning a Spring launch?

[AJZimm]

Just looked up the Pogy 17 on Tad's site, it's a more substantial boat than I thought:

• Displacement: 1,500 lbs lightship, 2400 lbs cruising
• Sail Area: 142 sq.ft.
• Ballast: Steel centerboard of 110 lbs

That's much heavier than my rowing skiff. Is the CoPogy the same?

All-up displacement will be a little lighter, about 2200 lbs, maybe less, depending on how disciplined I am in the build and how much stuff I bring along.
Sail area somewhere around 175 ft2
The centreboard will be steel, about 200 lbs, offset to make more usable footroom in the centre of the cabin

[AJZimm]

Glad to see that you're doing this. I found myself in the same position.

Metoprolol works wonders with the afib, and with zero side affects, unlike the older beta blockers. I only take it when it gets up over 200 bpm, then it's 25 mg. At 240 I take 50 mg. Less than 200 a glass of ice water, deep breathing and strenuous hiking do the trick so rowing may actually be good.

For me it's entirely stress related. Things that I didn't even notice before can be stressful enough to trigger it now. Aging is, well, I guess you've noticed.

There's a kit available to adapt the Tohatsu 6 to remote. You lose the manual tiller/throttle though.

6 may seem like overkill but at low rpms it's nice and quiet and at 2400 lbs. 6 should be just right. At 1/2 or more throttle it vibrates too much and is too loud for my taste, but don't/aren't all single cylinder outboards?

I'll be watching. Thank you for sharing Alex.

Gib, good to hear from you. Without turning this build thread into a medical one, I’ll expand a little on my experience, as it may be useful to other aging folks following this. I think there must be a lot of variation in afib manifestation. My afib episodes are highly periodic (“paroxysmal” in the medical jargon) and have happened mostly in the summer, strangely. I carried Metropolol around for 3 ½ years but never used it as my heart rate doesn’t increase much during episodes, the rhythm just goes screwy. Flecainide is what I take to reset back to sinus mode. I haven’t been able to identify any specific triggers except for extremely cold water or icy drinks, the opposite of your experience.
I have cut back on my caffeine intake (regrettably), have been drinking a lot more water for the past 8 months, and increased my salt intake a little, and this summer was much better, but I wouldn’t say I’m back to normal (how would I tell, my wife asks?) 😉

[AJZimm]

Very nice, Alex. Planning a Spring launch?

Thanks Dave. Spring launch night be possible, but not likely, I think. Hard to estimate how long this build will take. My last boat, Fire-Drake, took me 1,050 hours spread out over 17 months. Getting the hull finished to the point of turnover was a little more than a third of that, but, it was 11 planks per side. This hull is simpler but the deck and cabin are more complex, so it might end up the same number of hours, perhaps more. Can I squeeze all that into 8-10 months? Would be nice but I'm not counting on it.

[Hugh MacD]

Sorry to hear about your afib Alex, but I'm happy to be able to watch your new build. Looking forward to seeing your progress, Think you'll be able to get her down to the PTWBF next year (he says optimistically)?

[AJZimm]

Glue-up went fine, but for the first long panel I used an epoxy, called Ecopoxy, that I hadn’t used much before. It’s purported to be an eco-friendly epoxy, derived from plants. I wanted to like the stuff, as it is also cheaper, but I am having a hard time doing so. On all my previous boats, I have used Cold Cure, originally made by Industrial Formulators here in British Columbia, but acquired by System Three a few years ago. The Ecopoxy has a longer cure time – it says 48 hours, but in reality it took about 72, has a shorter pot life, requires a narrower temperature range and is more finicky to mix at a 4:1 ratio compared to Cold Cure at 2:1. For making boat pieces like panels where you want to glue it up one day and cut bits out the next, the 48-72 hours just doesn’t work. I’d also have to heat my shop much more with it. Both of these are deal-breakers for boat-building in my situation. I’ll use up the rest of my supply on less-critical pieces as the work progresses, but its back to Cold Cure for me in the meantime.

I laid out the strakes on brown paper to make a pattern, so I only had to do the layout once for each strake for both starboard and port sides. I used my laser level line to ensure a straight baseline for the pattern and then transferred the pattern with nails and batten to the ply. For the second strake of each pair, I checked the baseline on the pattern again with the laser level, to ensure that it hadn’t shifted.

Paper strake patterns


Transferring the lines


Cutting out the strakes



One strake is quite banana-shaped

[The Jeff]

Looking forward to following along!

[AJZimm]

Sorry to hear about your afib Alex, but I'm happy to be able to watch your new build. Looking forward to seeing your progress, Think you'll be able to get her down to the PTWBF next year (he says optimistically)?

That would be ideal Hugh, but not sure. In order to commit to the festival (assuming it goes ahead next year) and have half a chance of getting in, I would have to be sure, around about April, that I would have the boat finished by September. We'll see.

[jpatrick]

Following with great interest, Alex. And thanks for the brief history on Cold Cure. I bought some of their product way back in the early 80's for use on wood turnings I was making then. I didn't know jack about epoxy but they were recommended in an article in Fine Woodworking. It all worked out very well for what I was doing. Later (much later) I thought I'd buy more but couldn't find the company. Now I know. I love it when happenstance can bring experiences back full circle.

Jeff

[AJZimm]

Following with great interest, Alex. And thanks for the brief history on Cold Cure. I bought some of their product way back in the early 80's for use on wood turnings I was making then. I didn't know jack about epoxy but they were recommended in an article in Fine Woodworking. It all worked out very well for what I was doing. Later (much later) I thought I'd buy more but couldn't find the company. Now I know. I love it when happenstance can bring experiences back full circle.

Jeff

Happy to help, Jeff. The price went up when System Three bought it, to match their epoxy, but it's still good stuff. Never had a failure with it so far - 7 boats and some domestic projects.

[Rich Jones]

It will be great to see a never-built-before boat come to life.

[dbp1]

Not to derail, but I work in an unheated garage, so I'm curious about Cold Cure -- I used System 3's SilverTip, which with fast hardener says it cures to 35F (and that was my experience). Cold Cure says it cures to the same 35F, so I'm wondering what the difference is?

[hawkeye54]

Alex, may I ask what the 'orange bits' are in the 3rd photo in post #25 ?



Rick

[AJZimm]

Not to derail, but I work in an unheated garage, so I'm curious about Cold Cure -- I used System 3's SilverTip, which with fast hardener says it cures to 35F (and that was my experience). Cold Cure says it cures to the same 35F, so I'm wondering what the difference is?

Having never used SilverTip, I can't say. Maybe it's just resistance to try something new unless there seemed to be a compelling reason (i.e. plant-based, cheaper), but since I had always used Cold cure, I stuck with it. It has no amine blush, which is a bonus. Don't know how SilverTip behaves in that regard.

[AJZimm]

Alex, may I ask what the 'orange bits' are in the 3rd photo in post #25 ?



Rick

Rick, those are clips that come with a panel platform kit that Lee Valley Tools sells.

For those of us with small shops that have no room for a giant cutting table, cutting out long planks or strakes from a 24 foot panel is a challenge. These plastic clips are screwed on to a base and hold, by friction, sacrificial 1X stock, which raises the ply off the floor and gives enough clearance for circular saw or possibly a jig saw. I used 1 X 3's. The whole setup can be knocked down and set up easily. Cost a little bit, but it's such a slick setup and makes it very stable and to cut out the big strakes. Cost i s negligible compared to the overall cost of the boat in my view.

[Hugh MacD]

Those panel platform clips are slick! I had to look them up. How many kits did you have to buy and what's your spacing? Think that'd be sufficient to support 4mm ply?

[AJZimm]

Those panel platform clips are slick! I had to look them up. How many kits did you have to buy and what's your spacing? Think that'd be sufficient to support 4mm ply?

I bought 3 kits, which come with clips for 6 cross pieces each. I think I spaced them about 16" apart, which was fine for the 9mm. I'm about to scarf up some 6mm for the top strake and raised topside pieces. I'll let you know when I get to the layout and cutting how bendy that spacing is for it. I suspect you might need closer spacing for 4mm.