PDA

View Full Version : Arctic Tern Turned



mcdenny
01-26-2010, 08:44 AM
I've been working on an Oughtred Arctic Tern this winter and just got it turned over this weekend.

http://im1.shutterfly.com/media/47a0df07b3127ccef960816f50c400000030O00AZM2rdm3ct2 IPbz4C/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

My daughter, Ami, is co-owner, sailmaker and color selector. I'm a white with a little varnished trim kind of guy but followed her instructions for purple topsides and dark green bottom. I have to say it looks pretty good and certainly will get some attention on the water. Interior will be the same greenish grey as the boot stripe with natural garapa floor boards and (maybe) seats.

The hull took four sheets of 9mm Meranti ply, stems, keelson, floors are sassafras, keel is garapa. The hull sitting there only weighs 180 lbs. Piece of cake to turn over by myself.

Her dog is named "Bosun" but has not helped at all!

johngsandusky
01-26-2010, 08:50 AM
Wow, that boat is striking. You must be very proud of the daughter and the boat. Congratulations!

James McMullen
01-26-2010, 09:30 AM
Sweet! Now add just a few little details and you'll be sailing in no time.

Rich Jones
01-26-2010, 09:37 AM
A beautiful boat and a hearty looking crew. Well done! Plus, I'd die for your workshop. Keep the pics coming.

Thorne
01-26-2010, 10:17 AM
Lovely! More pics, please....

mcdenny
01-26-2010, 12:41 PM
- a few little details, I wish. All the spars are done (sitka sprice birdsmouth) as are rudder and centerboard (garapa).

I'm really glad some people here and at a couple of wooden boat shows turned me on to sassafras. Clear, light weight, easy to machine and smells like root beer at only $2/bdft. Looks just like oak or ash.

I'll post another pic when I get sheer clamp and lower edge trim on.

kenjamin
01-26-2010, 12:52 PM
Ya done good, son!

Are you going to meet the master himself at this year's Woodenboat Mystic show?

Hope to see you there and keep up the good work!

Is your daughter lobbying for tanbark sails or cream?

mcdenny
01-26-2010, 01:03 PM
Hey Ken, Good to hear from you. Ami is building the sails from Sailrite kits (4oz white, got to have some contrast to that purple hull.)

I'd love to take the boat to the WBS this summer and meet Iain, he was delightful to chat with on the phone. If I go, though, I'll be bringing the Harmony 25 elctric launch to offer for sale. My timing really sucked for going into the boat business.

RodSBT
01-26-2010, 01:08 PM
How was the Meranti to work with? Any problems with it bending into shape?

And great job! The hull looks wonderful!

Bill Perkins
01-26-2010, 01:29 PM
A beautiful boat , congratulations . I'll be watching your build with interest .

As to the Sassafras :it's also highly rot resistant, and available at many sawmills in the East .

kenjamin
01-26-2010, 02:15 PM
Yo mcdenny,

Do you mean to tell me that beautiful, award-winning, well-mannered, extremely quiet boat of yours hasn't sold yet?

I very much enjoyed my ride in Harmony, judged Best Owner-Built Powerboat at the 2009 WoodenBoat Mystic Seaport Show. I was particularly amazed at the control you had at the helm. When I asked you to bring me in a little closer to get a photograph of the Egret sharpie, you just whirled it around and held position. And it was really nice to have easy conversations over the low hum of the electric power plant a very enjoyable boat! This will make someone a fine and very quiet motor launch (if I had the money, she'd be mine![no profit for me if she does sell]):

http://ford.physics.fsu.edu/Electric2559.jpg

htom
01-26-2010, 02:22 PM
A beauty, just as she is. Gilding is not needed, it would only distract.

mcdenny
01-26-2010, 04:49 PM
Rod, The 9 mm meranti was easy to bend - 3 or 4 drywall screws with washers held it to the stem until the epoxy kicked off. I considered okoume but the weight savings would be moot as the boat needs some ballast anyway. The meranti is stronger, more rot resistant and cheaper.

Ken, The Arctic Tern will have an electric drive system too, the business end of a trolling motor with a fairing and an APC prop mounted in a clever but yet-to-be-designed well. I believe she will go 10 miles at 4 mph on one 50# battery. My experiments with a canoe last fall support this but you never know... Just in case, I'm going to make a pair of hollow shaft 'birdswing' oars, stealing your idea, so they match the curve of the side seats for compact storage.

JimD
01-26-2010, 06:04 PM
Looks reeeeaaally sharp. More pics, please.

chill
01-26-2010, 06:18 PM
Very nice

Clinton B Chase
01-26-2010, 09:19 PM
My God that is gorgeous!!!!!! Great job.

James McMullen
01-26-2010, 09:49 PM
I love working with Sassafrass too. . . but I have a hard time finding any out here where I live. Both Edensaw and Crosscut Hardwoods have standing instructions to call me if they ever bring any more in.

Bob Triggs
01-26-2010, 10:15 PM
Very nice!!!

simonmags
01-26-2010, 10:35 PM
Hi Denny, very nice boat, I like the electric motor idea too. Have you though about just using a permanently mounted inboard? I saw these motors and they peaked my interest...
http://www.technipowersystems.com/motor-drive-units/st-37-specs

Anyway well done on a great looking boat, who was the design by?

mcdenny
01-27-2010, 08:33 AM
That's a little more motor than I need, 144v! A permanent motor would be nice but I don't want the weight, complexity or drag under sail. It's a very light boat with only 102 sq ft of sail. When I get the motor arrangement figured out I'll post the details and also performance data next spring.

Iain Oughtred is the designer. He has several sizes of double ended beach boats like the Arctic Tern. Great plans with full size patterns for the molds and stems.

kenjamin
01-27-2010, 09:17 AM
Denny,

Just for the record, the majority (60%) of the rights to my birdwing mast belong to FSU. I'm just the guy who came up with it. They are the ones spending all the money on a patent. As for oars, curved oars did occur to me but I thought they would be too awkward to use. Let me know how that works for you. If you're doing hollow oars, why not do a two piece oar with a mahogany core piece for the connection? Also I've found Iain's double enders can be very effectively paddled (like a big canoe) with a five foot ash paddle while sitting near the stern post.

James McMullen
01-27-2010, 10:00 AM
Birdswing oars? Oh dear god, the madness is spreading!

Here's my advice: make up a cheap mock up--doesn't matter how crude, a plywood blade tacked to a 2x8 with the curve sawn into it would be fine--before you spend a dime or a minute on building a deliberately warped oar. I think you'll find out pretty quick whether or not you are willing to put up with the misery of trying to row using an oarshaft with an unbalanced moment of axial rotation. Unless you somehow manage to counterbalance the axial weights exactly at the exact point of the oarlock, that thing is going to try and twist in your hands before, during and after every single stroke.

Sculling oars are sometimes made with a curve, but then they're supposed to flop from side to side during the sculling stroke.

I haven't found stowing straight oars to be particularly in the way in Rowan, but if you must find a method of storing them even smaller, I think you're going to be better off with two-piece oars instead.

kenjamin
01-27-2010, 10:13 AM
James, I guess it was bound to happen sooner or later we actually agree on something.

I, Rowboat
01-27-2010, 10:49 AM
Birdswing oars? Oh dear god, the madness is spreading!

...

I haven't found stowing straight oars to be particularly in the way in Rowan, but if you must find a method of storing them even smaller, I think you're going to be better off with two-piece oars instead.

The stowage issue is really quite a red herring on these and most other boats. Dragonfly's oars are almost a foot longer than Rowan's, and it's still a non-issue. The reality is that very few people will ever spend much time forward of the center thwart, which gives you the space forward of those thwart knees all the way up to the stem. And you can poke them even further forward by going up over the breasthook -- they'll nestle nicely between the stemhead and the fairleads.

Birdswing anything sounds like a badly-conceived novelty solution looking for a problem to fix.

A far greater challenge is where to stow the crab pots.

kenjamin
01-27-2010, 11:36 AM
No matter what it sounds like, if we didn't look to nature for design solutions, we would not have velcro or hundreds of other inventions. If you think it is a waste of time to make masts more aerodynamically efficient, then you must not go to windward very often. Prototypes of inventions are often crude and do not work nearly as well as the final product so please excuse my first attempts to create something new and different. If you think that all the good ideas have already been invented, you're just plain wrong.

Sorry for the thread drift, Denny. Great job on your Arctic Tern. Hope to see you at Mystic!

mcdenny
01-27-2010, 12:38 PM
I have to admit I did not think about the CG of a curved oar creating a moment about the handle center line. Good catch. I may take a shot at the math, though, to see what the actual moment would be.

jonboy
01-27-2010, 01:31 PM
The big problem with this boat is you have to build two....

one good tern deserves another

rregge
01-27-2010, 03:52 PM
Denny

She looks great, and that was fast (or was I just slow)?

Do you have any pictures of making the spars?

You are now ahead of me.

Looks great

Russell

James McMullen
01-27-2010, 06:15 PM
Let's not get too far off topic, Kenjamin, but I think you have very much still to prove on your assumption that you have made anything more efficient with your "birdswing" mast rig thingie. I won't argue if you say that you like the way it looks or that you're happy to shut up your loud-mouthed fishing buddy who complains about a mast in his way, but until you prove that your rig goes upwind better or even as well as a competently handled, lug rigged version of a CY, you'd better stop making that sort of outrageous claim. I don't think you have the slightest bit of data to prove your too-flat, wrinkly, stiff-battened sail with that big sculptured and curved stick with its uncontrolled rotation impeding the luff flow has less drag than a modern dacron lugsail with its gloriously unobstructed and efficient leading edge. You still haven't sailed side by side with a CY constructed to Iain's stock plan yet, have you?

There's nobody--including long-time modern fiberglass sloop owners (like myself, formerly!) who would complain about how well a CY with a good lugsail goes upwind. And in my opinion, it's a vastly simpler, handier and more cost effective rig than a heavy, laboriously sculptured, axially unbalanced, curved spar with full battens and sail slugs that need to be inserted into a luff groove to set sail. Caveat emptor.

Here's another thread (http://www.woodenboat.com/forum/showthread.php?t=108685)with a video of a CY in action. Watch how well it sails upwind.

mcdenny
01-27-2010, 06:27 PM
Russell, I'm fortunate to be retired so can spend most of these dreary winter days in the shop. I'm not keeping track of time but I'd guess I have maybe 300 hours in the boat so far and it's maybe 1/2 to 2/3 done. I hope to have it ready to go when we get some nice weather in late April or early May.

I built the spars first so I could use the building frame as a spar bench. Rudder and centerboard got built as fill in jobs when I'd epoxied myself into a corner before quitting time. I'll see if I have any pictures but they are pretty standard birdsmouth construction, all but the mizzen boom which is not much more than a broomstick.

mcdenny
01-27-2010, 07:48 PM
Russell, I did find a couple of pictures of the main mast:

http://im1.shutterfly.com/media/47a0df06b3127ccef963a582a96b00000030O00AZM2rdm3ct2 IPbz4C/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

http://im1.shutterfly.com/media/47a0df06b3127ccef962958a893700000030O00AZM2rdm3ct2 IPbz4C/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

http://im1.shutterfly.com/media/47a0df06b3127ccef9632c70e94500000030O00AZM2rdm3ct2 IPbz4C/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

An inside out sanding belt driven by the electric drill chuck wrapped with two sided sticky tape worked great to go from 16 sided to round. Sort of a ghetto version of the Bud McIntosh spar finishing machine.

RodSBT
01-27-2010, 10:53 PM
"An inside out sanding belt driven by the electric drill chuck wrapped with two sided sticky tape worked great to go from 16 sided to round. Sort of a ghetto version of the Bud McIntosh spar finishing machine."

I like It :D!!!

I'll have to make note of this when I get to the mast.

Now to finish the present project to make room for my own Arctic Tern build. (so many pretty boats, so little time!)

rregge
01-28-2010, 10:29 AM
Denny

What is the center of the mast made of DF?

Where is a good place to go to learn to build a mast that way?

Russell

mcdenny
01-28-2010, 12:57 PM
The plug is western red cedar because that's what I had in the scrap box.

If you google birdsmouth mast or spar you will get some helpful links. Its way easier than building a boat. You need a table saw and fussy setup to get the V groove just right. A router would probably cut the groove just fine too but I hate routers. I planed a taper into the staves after cutting the V groove to result in a tapered, constant wall thickness spar. The handy calculator in the link above gives you the stave width for any particular diameter. Lay out one stave with a batten, plane to the line and use that as a master to mark the other seven.

I calculated the weight of a solid spruce mast at 22# and the hollow one at 13#. It's probably around 15# with the plugs.

mcdenny
01-28-2010, 08:46 PM
Russell, Just for fun I got the spars down and weighed them.

---------------------------calc solid weight-------------- actual b'mouth weight
Main mast -------------------22.7 -------------------------14.4
Main boom -------------------9.6 ---------------------------6.6
Main yard ---------------------6.8 --------------------------5.0
Miz mast ---------------------7.9 ---------------------------4.6
Miz boom --------------------1.8 ---------------------------1.5
total -------------------------48.8 -------------------------32.1

Miz boom is solid.

Clinton B Chase
01-28-2010, 09:17 PM
Denny

What is the center of the mast made of DF?

Where is a good place to go to learn to build a mast that way?

Russell

You can look here, a page I created for instructional purposes, particularly demos that I do at boat schools.

http://tinyurl.com/birdsmouth

Cheers,
Clint

RodSBT
01-28-2010, 10:08 PM
Thank you Mr. Chase, the link is now bookmarked.

mcdenny,
those spar wt.s are nice! Outta be able to throw that rig up in no time... or take down when the big blow comes rolling in.

darroch
01-28-2010, 11:28 PM
A beautiful boat, lady, dog...a worthier trinity ye'll be hard-pressed to find.

rregge
01-28-2010, 11:35 PM
Thanks for the info and the link.

Looks like fun, and a big savings over solid wood

Both $ and weight


Russell

mcdenny
01-29-2010, 07:57 AM
Clint, Nice write up of your spar building process.

Clinton B Chase
01-30-2010, 07:08 PM
Denny, Thanks. I would love feedback, questions, etc...will help me prepare for them from students. You can send feedback through my website.

Thanks and I can't wait to sail in your boat Denny...I've been looking at doing an AT for too long.

gazzer
02-12-2010, 07:54 PM
Denny,

Great progress, I know that you started your AT after me and I am just now doing the tedious sanding of the outer hull, which I completed early December. Cold weather has certainly slowed my progress.

Have you gotten your rudder hardware yet. I'm curious about what you have in mind. I can't bring myself to order from the UK, so I am contemplating making patterns for a local foundry to use.

As said above, all your pics are welcome.

-G

mcdenny
02-13-2010, 08:31 PM
I got these from Duckworks:
http://www.duckworksbbs.com/hardware/p-g/weekender/weekender.jpg

$65 for the set. I'd rather had bronze but these were all I could fine short of the Classic Marine pieces that are apparently custom made to order (slow and expensive).

The Duckworks parts are a tad heavy for the scale of the AT but fit and look OK. It took a lot of fussing to get the gudgeons let into the stem such that they are on the same CL so the rudder pivots freely. I may want to replace the two short pins with one long one depending on how fiddly the pair are in use.

I'll try to remember to post a picture when I get home next week.

mcdenny
02-24-2010, 09:19 AM
I finally got the gunwhales finished - what a fiddly PITA. They look nice, though, and I like the detail the open rail with simulated rib ends provides.

http://im1.shutterfly.com/media/47a0dc05b3127ccef9258ad1153c00000030O00AZM2rdm3ct2 IPbz4C/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

Outer rail is two layers of 1/2", one 3/8", tapering to just 3/8" at the ends. Inner is 3/8" with 5/8" x 1-1/8" blocks 6" oc. Blocks + strips + breasthooks = 90 pieces of wood :eek:.

http://im1.shutterfly.com/media/47a0dc05b3127ccef925995fd41300000030O00AZM2rdm3ct2 IPbz4C/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

Next up is building the c'board trunk.