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phisherman
02-02-2005, 02:45 PM
Has anyone built an atking bluebird. the lines appear similar to old lifeboats. I contacted atkin plans to try and get info but all they told me was the ballast should be 430lb lead in or outside. I did some calculations and extimate total disp at around 1 ton. My main question is will this design work for lapstrake construction. My guess is yes but atkin makes discouraging comments against changing the construction details. bluebird is 18' overall 16' waterline draws 2' on a beam of 6'10". does my disp calc seem close, I am afraid it might be low. any suggestions would be helpful. I am not however interested in building her with plwood laps or using the designed carvel construcion.

RonW
02-02-2005, 04:35 PM
Very neat little trailerable sailboat. And I would be willing to bet quite capable at that.
I like the inside ballast and no keel.

A couple of comments, I suspicion that the frames are bent white oak. If you want to get away from carvel, it looks as if this boat would be a perfect candidate for traditional strip planking. Leave everything as he designed it, just put strip planking on it instead of carvel, even the same thickness, probably 3/4.(no cloth)
Atkin talks about strip planking and was very in favor it.Look at his articles on the same site.
If you wanted to lapstrake it, again leave everything the same, just use douglas fir marine ply, maybe a little thinner like 5/8 to compensate for the laps, and why glue it, why not just fasten it traditionally with rivets, screws and clenched nails. I have examined many boats built like this from the 1950's, and they hold up very well.

If you read Atkin, as I do, you will see that he was sick and tired of people buying his plans and playing backyard architect and then crying to him about their results.I don't think he was as opposed to different construction methods, provided there was on the same weight and strength guidelines, as he was to hull deformation and weight redistribution.
But who could say it better then him. Here is his quote from the same page of your boat.

---Atkin says---In the matter of headroom what more might one expect in this little boat. I know there will be builders who will lower the floor, raise the height of the sheer, the height of the cabin sides, the house top crown, and many seemingly small items in an effort to improve the design or to make it adaptable to some very particular requirement. And in about six months I'll receive a letter telling me the boat does not perform as specified and that I should not encourage people to build boats at all. If you will leave her as she is, then you will have an excellent little boat, measuring up to all expectations. --

The man has a wonderfull way with words.

holzbt
02-02-2005, 04:36 PM
http://www.boat-links.com/Atkinco/Sail/images/BlueBird-3.gif

Looks like changing to lapstrake should be no problem. The specs call for 3/4" white cedar planking on 3/4" x 7/8" steam bent frames on 8" centers. You could probably decrease the plank thickness slightly (5/8" + or -) and leave everything else as spec'd.

RonW
02-02-2005, 04:46 PM
- Holzbt- Where did you find the specs for the bluebird, or do you already have the plans for it?

imported_Steven Bauer
02-02-2005, 04:54 PM
What a cutie!

http://www.boat-links.com/Atkinco/Sail/images/BlueBird-1.gif

Jack Heinlen
02-02-2005, 05:30 PM
Ron W,

Here is an alphabetical list.

http://www.boat-links.com/Atkinco/BoatList.html

Be ready to spend a few hours, and a few more, and a few more. smile.gif

Check home if you want to go at it by boat size and type.

RonW
02-02-2005, 05:39 PM
Thanks Jack, but I got the Atkin site and have already spent 2,489 hours and 32 minutes on it.

- But Holzbt, spells out 3/4 planking, 3/4 by 7/8 bent ribs on 8 inch centers, so he must have the plans or inside info from somewhere.

Anyhow it is good that you posted the site for one and all to indulge in.

Venchka
02-02-2005, 05:51 PM
Aye. First it's just a quick peek at the Atkins' site. Then another. One more peek can't hurt, eh? Then you're hooked. Time for the 12 Strake Program! :D

By the way, holzbt is psychic.

Wayne
In the Swamp. :D

Dave Fleming
02-02-2005, 05:57 PM
Nah Roger ain't no mind reader. :D

He has every volume of the Motor Boating Ideal Series ever printed. Is all. ;)

holzbt
02-02-2005, 06:37 PM
The plans are in Volume 47- Workable Plans For Practical Boats.

I'm missing a few volumes- If anyone would like to donate volume 3 or 25 I'd gladly accept! I'm missing a few others but they don't contain plans as far as I can find out.

If I were converting to plywood lapstrake I don't think I'd go over 1/2" thickness.

Jack Heinlen
02-02-2005, 07:01 PM
- But Holzbt, spells out 3/4 planking, 3/4 by 7/8 bent ribs on 8 inch centers, so he must have the plans or inside info from somewhere.
I see, I misunderstood.

And I agree with Holzbt that the tuck would be quite plankable in lap, and with 5/8 +- for the scantling. Just out of our heads. I'm relying on him, 'cause my "head" is a bit old in these matters.

Venchka
02-02-2005, 07:30 PM
As the owner of a slightly longer glued lap plywood boat made with 1/2" and 3/8" plywood with 3/4" laps, I would hazard the following:

If the right person who had both the EYE and the GIFT lined her off and IF that same person used doug-fir or sapeli plywood I venture Bluebird could be built with...

1/2" ply to the waterline
3/8" above the waterline
3/4" laps
laminated doug-fir or mahogany frames 1"x1" or maybe molded 1-1/2" on 16" centers, maybe even 24" centers
1-1/2" sided doug-fir floors to hold her bottom together

or 1/2" strips and two veneer layers of WRC totalling 3/4", few if any frames and the same 1-1/2" sided floors

...but I have no idea what I'm talking about.

Mumbling out loud. :eek:

Wayne
In the Swamp. :D

Keith Wilson
02-03-2005, 09:56 AM
Y'know, Bluebird is a lovely boat, and would be even prettier lapstrake, either glued plywood or traditional. However, with all respect to the Atkins, it looks to me like she's got VERY little lateral plane, at least by the standards of the past 60 years. I thought she had a centerboard at first, but nooooo . . . It looks to me like she wouldn't point high, and would make a LOT of leeway if sailed at all close to the wind. Maybe I'm just prejudiced after sailing a Thunderbird, which was very good in that respect, but I really like modern boats' windward ability. Perhaps those who know more about sailboat design than I could comment.

phisherman
02-03-2005, 07:48 PM
aye, the lateral plane issue concerned me a bit also, but the fact that the keel, ballast and deadwood all appear to be fairly square makes up for it, in that I will be able to make the casting, this will be the firest large casting for me. I have begun lofting her 3" to the foot, to get a better idea for the lines while I wait for the plans to arrive. the reason I am leaning towards traditional lapstrake is 1) where I am at it is more affordable to get oregon pine timbers than doug fir plywood. 2) the boat is going to be built with hand tools only, besides the rough cutting of of the keel and stem assembly and using a planer to trim the planking to proper thickness, because though I have access to stationary tools they are a good drive from my building site. this boat is going to be built on the sidewalk in san francisco. crazy you say, I already have the permit, so its to late. the only kink is that the sidewalk is at an angle, about 6 degrees, but fortunatly this is about the angle the keel bottom sits at relative to the molds. pretty lucky huh, I think this will allow me to build a flat base to hold the keel and naturaly put the keel at the correct angle relative to the molds, does this sound legitamite, or am I asking for trouble. anyway thanks for all the advice and if you got anymore let me hear it

Venchka
02-03-2005, 07:57 PM
Lat. & Long. of the building location so anyone who happens to be in the neighborhood can look in on the progress, lend a hand, convey encouragement, donate beer or other essential materials. :D

Hmmmmmm...Oregon pine? What wood might that be? Or am I just dense? Have you heard about the old timer across the Bay who was forced to liquidate a huge stash of old doug-fir and other local lumber? Somebody brought it up here at the Forum in the last year or so. Might be a good source of timber for the backbone. SEARCH feature here might find it.

Wayne
In the Swamp. :D

RonW
02-03-2005, 08:05 PM
Any more advice?.....Yea do it...and don't give up till it is done.......

phisherman
02-03-2005, 08:32 PM
wow thanks for the tip on the salvaged wood, salvaged wood is definately what I am looking for, good and cheap. being from oregon, we call douglass fir oregon pine, as it is truly a pine species. my location is outer richmond on balboa in san francisco, I'll be here nearly every day once I start so feel free to stop by, or let me in on other lumber sources

holzbt
02-04-2005, 05:16 PM
If you are planking with d. fir/oregon pine I'd think your planking should be closer to 1/2" than 5/8". This should keep the weight about the same and help with the twisting that will be required in some areas.

Steve Miller
02-04-2005, 07:49 PM
I always thought the latin name for doug fir meant false hemlock. Never connected it to pine trees which are not all that common in Western Oregon since the native forests are douglas fir and hemlock. Gotta go east of the mountains for pine trees (lodgepole, ponderosa, some spruce).

So I looked it up. The firs, pines, hemlocks and larches are all part of the pinaceae family of trees. Learn something new every day on this forum.

Douglas Fir: Pseudotsuga menziesii

donald branscom
09-05-2006, 01:01 AM
Has anyone built an atking bluebird. the lines appear similar to old lifeboats. I contacted atkin plans to try and get info but all they told me was the ballast should be 430lb lead in or outside. I did some calculations and extimate total disp at around 1 ton. My main question is will this design work for lapstrake construction. My guess is yes but atkin makes discouraging comments against changing the construction details. bluebird is 18' overall 16' waterline draws 2' on a beam of 6'10". does my disp calc seem close, I am afraid it might be low. any suggestions would be helpful. I am not however interested in building her with plwood laps or using the designed carvel construcion.

I am also wanting to build bluebird (Atkins) and saw your post.
2000 lbs seems about right.

I was going to build in 10 or 12 gauge steel or strip plank.
I am more familiar with steel but round hulls take more work.