Sea Bird Yawl model

[Michael_Owen]

Hello all.
I have begun construction of a 1/6 scale model of the Sea Bird Yawl. I have the plans from our hosts. It will be pretty big for a model because I want to try to make the build as close to the experience of building a full-size boat as possible.

It's been fun so far. I "lofted" the boat "full-size" by doubling the sizes from the plans. This was going slowly until I switched to metric. No more trying to figure out what twice "3 and 13/16ths inches" was in my head!

I've gotten out most of the backbone structure, and now I'm wondering about how/when to bevel the keel. It stays its full width along its top face as far as I can tell, and I've laid out its bottom from the half-breadth plan. I can see the different widths at the rabbet line for each station on the body plan. I'm just wondering how to measure these.
For my model I suppose I can use calipers, but what to do in real life, with a giant piece of oak?

Hope I've made myself clear. Any thoughts appreciated.

const. dwg..jpg

backbone.jpg

CB slot.jpg

Mike

[Peerie Maa]

I'm wondering about how/when to bevel the keel. It stays its full width along its top face as far as I can tell, and I've laid out its bottom from the half-breadth plan. I can see the different widths at the rabbet line for each station on the body plan. I'm just wondering how to measure these.
For my model I suppose I can use calipers, but what to do in real life, with a giant piece of oak?
Mike

When lofting full size, the loftsman/shipwright would make templates of the rebate at each station or waterline on the keel, stemand apron assembly, and stern post deadwoods. Then the timbers can be marked out from these tempates and the marks joined up with battens.
Then short sections of the rebates are cut at the build moulds when they are erected to check the accuracy of the lofting, which are then connected together.

[Peerie Maa]

Originally Posted by Michael_Owen
I'm wondering about how/when to bevel the keel. It stays its full width along its top face as far as I can tell, and I've laid out its bottom from the half-breadth plan. I can see the different widths at the rabbet line for each station on the body plan. I'm just wondering how to measure these.
For my model I suppose I can use calipers, but what to do in real life, with a giant piece of oak?
Mike

For your model.I would erect the frames upside down in a jig, a bit like this:

Erected frane B.jpg
Then I would dry fit the mid line structure to the frames in the building jig and mark the rebate from the frames.

[Michael_Owen]

Thanks, Nick. I have been wondering about upside-down vs. right-side-up. I have made six molds with a common baseline for an upside down build. I've done one frame, but forgot to deduct planing thickness. I'll build some more soon, and will make "legs" to the baseline, with cross-spalls to stiffen them.

I often have to get the 3-D parts in my hands in order to comprehend the steps ahead.

Mike

[Peerie Maa]

Thanks, Nick. I have been wondering about upside-down vs. right-side-up. I have made six molds with a common baseline for an upside down build. I've done one frame, but forgot to deduct planing thickness. I'll build some more soon, and will make "legs" to the baseline, with cross-spalls to stiffen them.

I often have to get the 3-D parts in my hands in order to comprehend the steps ahead.

Mike

Once upon a time, not so long ago, all boats were built the right way up. Nowadays even small dingys are built inverted, which is a PITA if you are building clench lap, so building your model inverted is not a dumb idea.
My jig is a flat board that captures and secures the heads of the extended fames.

[Michael_Owen]

I cut the slot fro the CB this afternoon at work. I started with trying to drill a million holes on the drill press, but I was using a long bit and maybe working too fast, so some of the holes were not coming out on the centerline on the other side. Ended up doing some plunge-cutting on the table saw. That was the way to go. The slot is a hair wider than designed but I think I can live with it.

Tonight, I'm gluing the sternpost to the keel. Doing it right on the lofting to get the angle right. This joint was not as good as I had hoped. Next up, stem, deadwood and stern timber will be attached, completing the backbone assembly. Then drawing the rabbet line on there. Oh right, I need to expand the transom and cut it out, and THAT will complete the backbone!

I'm looking again at Greg Rossel's "Boatbuilder's Apprentice."

Thanks for taking a look.

Mike

glue.jpg

slot.jpg

[Michael_Owen]

More progress on the backbone structure. I'll probably cut out the transom blank today. I need to remember to deduct the planking thickness from it.
I will need to notch the molds for the sheer clamps and bilge stringers, then set them up on the building jig. I'm learning as I go...

Mike

backbone 2.jpg

backbone.jpg

[Hugh MacD]

Love the scale you're working in! Thanks for taking us along!

[wizbang 13]

Oh that looks so nice!

[Michael_Owen]

Thanks, Gents. Got a bit more done this weekend. First the taper in the after part of the keel.
taper.jpg

Setting up some molds.
3 molds.jpg
Transom knee
Transom knee.jpg
Made a planking fid, which showed me that either a few of my molds or my rabbet line are a bit off. I'll have to sleep on it.
fid.jpg
And I've begun to notch the molds to receive the bilge stringer (chine log) and the sheer clamp. I'll put those members in to check the molds for fairness. I sense some trial and error ahead.
5 molds.jpg

Happy Solstice and all the other Holidays!

Mike

[nedL]

Looking good! This will be fun to watch,…. Thanks!! ����

[wizbang 13]

Would you build the real boat upside down?
for me, if the model is not built as the boat , one might as well just 3D print it.
The result is a beautiful model but it does not reflect the actual construction.

[Peerie Maa]

Would you build the real boat upside down?
for me, if the model is not built as the boat , one might as well just 3D print it.
The result is a beautiful model but it does not reflect the actual construction.

Does this not represent the actual construction?

[wizbang 13]

It shows the construction style of the boat of course.
But does it show the model builder all the idiosycr..idiosyncratic… idiocies… all the wacky things that will happen in real life and how to deal with them ?
Will building the model teach one how to build the boat?
that’s what I’m trying to get at I guess.
Its nice to hold a model up and make believe yer sailing around in her, look at her shape from a fishes eye view, put her in a pond even, but it may not be exposing a very expensive mistake that may happen on the vessel.

[wizbang 13]

I can see / envision Robb , ( or his son I guess) ,building a model of a boat and setting up tiny dioramas of dudes pushing a plank on, on lying downside up trying to caulk a trick spot in the way back .
Nick, Michael, don’t get me wrong, I just love them.

[Peerie Maa]

It shows the construction style of the boat of course.
But does it show the model builder all the idiosycr..idiosyncratic… idiocies… all the wacky things that will happen in real life and how to deal with them ?
Will building the model teach one how to build the boat?
that’s what I’m trying to get at I guess.
Its nice to hold a model up and make believe yer sailing around in her, look at her shape from a fishes eye view, put her in a pond even, but it may not be exposing a very expensive mistake that may happen on the vessel.

You cannot build a model like that if you do not know how the prototype was built full size, what techniques and tricks were employed, the order of construction.

[wizbang 13]

Well okay, it seems maybe for the two of us the model has a different purpose.
Perhaps yours is to exhibit the historical aspects for others.
For me it is to learn how to build the boat.

[wizbang 13]

How about this… I see sometimes folks will build a half model of a boat for display on a wall.
For me, that half model came before the boat , the first, did it not?
The retro made model is only for theatre, for display.
It teaches almost nothing.

[Peerie Maa]

Well okay, it seems maybe for the two of us the model has a different purpose.
Perhaps yours is to exhibit the historical aspects for others.
For me it is to learn how to build the boat.

It can be for both. My coble model was built right way up, shell first exactly as the prototype would have been. Both models were built to test my understanding of the prototype, as well as to create an historical record of boats that no longer exist.

How about this… I see sometimes folks will build a half model of a boat for display on a wall.
For me, that half model came before the boat , the first, did it not?
The retro made model is only for theatre, for display.
It teaches almost nothing.

Half models were design tools, but many builders also made a half model as a wall piece for the customer, or to use as an advertising tool.
There is a model of a liner, fully fitted out, on display in a museum collection. It started out as a design tool, for working out the butts and seams in the plating, then went back to the model shop for conversion to a dispaly model for the customer.

[Michael_Owen]

I will probably not be building this boat in real life. The primary purpose of the model was to keep me sane during the cold months of no sailing, and my basement stairs are too small for me to build the Atkin Handy Andy that I started last summer.

If I hit the lottery, though, the Sea Bird would be a worthy stretch of my abilities, and a nifty/capable boat to sail around my local waters.

Then, the decision to build right side up or not might be dictated by construction method. Carvel or strip? Carvel for the fun of trad. build. Strip for water-tight and more forgiving of my amateur skills.

Thanks for looking in!

Mike

[Michael_Owen]

A bit of progress. The molds are almost done, so I couldn't resist trying a very flexible batten in the notches for the sheer clamp. It'll need some fine-tuning, but it's nice to see.
When I tried the actual pine strips for chine and clamp, however, they seemed like they were going to require a lot of coaxing, especially edge-set. Wonder if I'll need to soak/steam them?

0-1.jpg

And because the computer allows it...
0-1 copy.jpg
Cheers,

Mike

[Peerie Maa]

Wonder if I'll need to soak/steam them?

Cheers,

Mike

Poring boiling water over them, and dry heat can do it as you bend them off the boat. Over bend a bit, and theu will spring back when you put them to place.

[Michael_Owen]

Soaking in a wet towel and then pouring boiling water on them worked pretty well. The bilge stringers are wider, so I should have soaked/heated them longer, but I got impatient after the sheer clamps went so well. Here are the stringers being introduced to the idea of bending in two directions. The clamps are on the table.
bilge stringers.jpg

And a side view.
clamp :chines.jpg
Here is where the sheer clamp meets the stem.
clamp at stem.jpg

I'll get these dry-fit and marked up, and then I'l take the keel/stem assembly of the jig and begin chopping the rabbet in some known locations. Also beveling the stem and bottom of keel-still a bit of a mystery. Then I'll be cutting loads of frames!

Mike

[Hugh MacD]

Looking good! Thanks for sharing this What are you going to do to cut the rabbet in at this scale?

[Michael_Owen]

Thanks, Hugh! Here are the tools I used to begin chopping the rabbet this AM. A nice marking knife I bought when taking a beginning woodwork class about 10 years back. Chisel, same. A bevel gauge I made about 5 years ago. Crappy mallet almost ruined by my neighbor using it to try to pound in metal tomato stakes. Lil steel rule.
tools.jpg

The rabbet started.
rabbet .jpg

Bilge stringers beveled.
bevel.jpg

Once I get the rabbet chopped out, I will try cutting some notches into the keel to accept the frame heels.

Trying to figure out the order of operations is tricky, but fun.

Mike

[Michael_Owen]

Well, chopping the rabbet was a bit of a mess. I have finished the starboard side, and I can say that I'm glad my first time doing this was so low-stakes. I have learned a lot, though and the second side should go faster and maybe neater. I know that some of the issue is the small size of the thing. The wood fibers are the same size as on a big build, but the rabbet is 1/6 the size. With that caveat, 2 photos...

0.jpg

0-1.jpg

Mike

[gypsie]

This thread is a delight. Well done for posting it!
Looking loverly btw. Is that Balsa?

[Michael_Owen]

Thanks, gypsie! My pleasure.

The centerline timbers are poplar and the frames are basswood. There's an art supply store right near work that sells bass and balsa for architectural models.
I'll be ripping clear white pine for planking, same as the longitudinal pieces above. I'll need to line off for that soon.

Thanks for following along!

Mike

[Hugh MacD]

I'm surprised to see bass tearing like that. Last stuff I used was incredibly fine grained, but I did need crazy sharp tools to get a clean, slick cut. Love the model, though! Have you seen Paul Pless' "Don't She Pretty" thread in the bilge? http://forum.woodenboat.com/showthre...on-t-she-purty

[Michael_Owen]

Hugh, this stuff is poplar. The frames are of basswood and work beautifully.
Well, I did get better at cutting the rabbet on the second side of the keel, but you'll just have to trust me on that.
Here you see the worst part of the worst side of the rabbets. But it is where I cut the first frame notch this morning. It went pretty well. Hoping/assuming that I'll get better at this with practice as well.
The frame and the little "garboard" mate pretty well. I'm glad I don't have to count on this garboard-to-keel joint to keep out water, though.

I did a bit of color coding on the construction plans to clarify things a bit.

notch.jpg

frame.jpg

frame:garboard.jpg

color code.jpg

code.jpg

Cheers!

Mike

[Hugh MacD]

Nice! Yeah...I've carved a little bit of poplar. The varying grain makes it a challenge. I found I had to keep my knives really sharp and take little "bites". I really like your model!

[AJZimm]

Re: Your rubber mallet.

I had one exactly like that, one that I had for many years. The rubber head, or whatever polymer compound it was made of that they called rubber, slowly got harder over time, to the point where it was so hard I was afraid to use it with my chisels. It happened gradually so that it took a while for me to recognize just how hard it had become. I finally went out and bought a new one and the difference is astonishing.

My understanding is that the rubber continues to polymerize over time due to exposure to temperature, light and oxygen. Same thing happens to car tires, which is why the tires on my vehicles age out before they wear out (I figure 6 years is about the max).

All of which is a long-winded way of saying you might be happier and have a better working experience wielding a new rubber mallet, and donating the old one to the neighbour so he can pound more stakes.

[Michael_Owen]

The next frame notch was a mess to cut, but ended up tight enough that the frame could support itself. A good sign, I suppose.
Note that the boat is not as beamy as this frame would seem to suggest. I need to lop off about a cm. from the length.

frame1.jpg

frame2.jpg

[Paul Schweiss]

This thread is a delight. Well done for posting it!
Looking loverly btw. Is that Balsa?

Sorry, this is a bit off the wall. What is a “chateratist”? The great Wizard of Google cannot enlighten me.

[Michael_Owen]

Not much visible progress to report. I'm about 3/4 of the way through cutting notches for frames into the keel. Probably need to set up the bedlogs and CB trunk next, before framing out.
Here are some notches.

Mike
notches.jpg