Cad design Alfred stern cad designing

stuglo said:
You guys are the theoretical mathematicians of model building. Don't understand what you are saying, but still very impressed !
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I won't lie to you this is really hard to do and I am stumbling through it.
the topic is showing all the back round work that goes into creating a kit and also not to scare anyone away from taking on a scratch project but you really need to have a firm grip on concept, design and an understanding of the structure. Then once you have a grip on that you need to figure out how to do it.
 
I have heard the saying "oh you guys make it look so easy" you know why it LOOKS easy because you did not see the first 10 tries.

ok here is the stern timbering the light blue ghost line is the fashion timber that holds up the ends of the wing transom.

stern timbering.JPG
 
the blue ghost line in the last post is the fashion timber and it is the last hull frame. This timber rests against frame Z and goes up under the wing transom.

fashion timber1.jpgfashion timber2.jpg
 
I too do not understand a word that is spoken here, BUT DO UNDERSTAND THE FINAL OUTCOME, PLEASE DAVE AND GARY explain to me the difference between what you are doing and what DONNIE POSTED ON THE Le ROCHEFORT log and what DAVE did for me on the CAUSTIC, i just can not grasp what is going on,. GOD BLESS AND STAY SAFE. Don
 
donfarr said:
I too do not understand a word that is spoken here, BUT DO UNDERSTAND THE FINAL OUTCOME, PLEASE DAVE AND GARY explain to me the difference between what you are doing and what DONNIE POSTED ON THE Le ROCHEFORT log and what DAVE did for me on the CAUSTIC, i just can not grasp what is going on,. GOD BLESS AND STAY SAFE. Don
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what you are seeing here are the first stages of research, design and drawing of a stern of the Alfred. Hahn created a simpler version of the stern construction in his drawings and model. He did this so the average model builder can actually build it. Hahn also took artistic license, keep in mind back when he did his model there was no internet and research was extremely difficult.
Once the "working" drawings are complete, then step 2 is creating a 3D model of the stern and all the laser and 3d printing files will be done from the master working file.
What Donnie is doing is creating instructional drawings a "how to" do something which is different from what is going on here, this is about designing.

what I did for Don on his building of the Caustic is to take the drawings

_caustic_2_.jpg_caustic_3a_.jpg

imported them into a 3D program


_3d1_.jpg
 
I did not see a reason why Hahn added that extra planking out from the cabin wall to the balcony, it makes more sense to just run the deck planking out
 
shaping the lower filler transoms
see those numbers behind the stern from 7 to 12 is the transoms my first thought was the arc in the lower drawing would give me the shape. Then on second thought i am not so sure. so the question to Gary is how did you get the shape of the transoms?

if I were building this I would just put over sized pieces of wood in and sand them to shape BUT I need to draw them which got me wondering how
img019.jpg
 
Hi Dave, like my late wife said (he is just slow),, i got the part of what you said about DONNIE it was an instruction but not of a specific ship, when you did the caustic for me you already had everthing you are doing now done so all you had to do is what DONNIE did only for a specific ship, am i correct. Don
 
I think I got it the ends of the waterlines are actually the shapes of the filler transoms. What i did was to trace the waterlines you can see the trace lines in red

tran2.JPG

the waterlines are numberes

tran2.JPG


i will use waterlines 8 to 12 for the shapes of the transoms

tran1.JPG

here are the results

tran3.JPG
 
Very interesting topic guys and I miss seeing your progress Gary now that I am no longer on MSW.

To add my twopenuth,the planking would have run through creating what is known as a cantilever or sprung balcony.This technique is still used in modern construction,I built two sprung balconies when I extensively remodelled our previous home.
Not all period ships relied on this method,many included support in the form of structural carvings or iron gussets.

Kind Regards

Nigel
 
Gary if they had the planks doubled to increase strength in line with the deck planking on top,I would imagine this would run continuously inside the cabin area to produce the cantilever effect.How far it ran inside would be the million dollar question.My guess would be at least double the balcony projection,but I have always been known for my belt and braces approach ROTF
I have found that these sprung balconies have deck planking run through parallel to the vessels centreline.Balconies supported by Carvings or iron gussets have deck planking running athwartships on the balcony.

Kind Regards

Nigel
 
Hi Gary,yes I think the immediate assumption is that these details are for decoration,I think it is more a case of the structural support is built and then made to look decorative afterwards.If we look at examples of the very ornate examples of the French first marine which have balconies in abundance,the assumption is that the vertical carvings are just there for show.I feel there is a structural element at work here.We have a combination of sprung and gusseted balconies but are linked into a strong and unitary structure by these carvings.Some carvings may be in tension,some in compression depending on the vessel and placement.

Kind Regards

Nigel
 
cantilever has much more structure support behind than what overhangs like this

cantilevered-deck-frame.jpg

the force of the red arrow is pushing down on the balcony which includes the weight of the sides of the balcony. This force will create a counter force pushing the planking upward like the blue arrow

bal cant.jpg
 
I traced Hahn's drawing from the cabin wall out to the edge of the balcony the lines between are the stern

bal2.JPG

taking a close look at Hahn's model you see the planking

SCN5148.jpg

changing the angle now you see a margin plank pointed to by the arrow

SCN5355.jpg

bring the structure into CAD

bal1.JPG
the outer margin plank is the arced lines so what is holding it up? you need some beams or joists running in the direction of the green arrows.
As for the planking like a deck it needs beams running in the direction of the blue arrow. Yes the ends of the planks could sit in a rabbit along the edge of the margin plank but structurely i don't think that would hold because it has to support the weight of the balcony sides.
 
Gary's post #134 is showing the underside of the balcony with fancy paneling. This is like the floor joist in a house the top of the joist would be the upper floor and the bottom or ceiling would be the room below. So that finish work on the under side of the balcony would not have been nailed to the underside of deck planking so there must be some structure like floor joists. I think
 
You know guys,some times I wish I had become a carpenter instead of a electrician. ;o) Dave you say that the finish work fancy paneling would not have been nailed to the deck planking above and wonder why do you say it wasn't nailed? if it was not nailed to something what kept it in placed?

I was saying the fancy finish work at the top (roof) of the balcony I don't think was nailed directly to the underside of the planking there had to have been some sort of beams or joists or some sort of structure between the deck and the roof of the balcony.

looking at this cantilever balcony the joists that the deck is nailed to sits on a 14 inch thick stone wall

DSCN2331.jpg

looking at the inside the joists run 4 feet in past the stone wall. Now the plywood floor would be the balcony deck and the fancy finish work would be nailed to the bottom of the joists. Deck planking could not just run out past the stern without some sort of support structure

DSCN2330.jpg
 
I looked through my archives and this is what I found

as you can see here there was no fancy paneling and moldings on the roof above the balcony. There might of been i don't know, but Harold just left it plain and flat. He did not even bother to plank it and we know that could not have been just one big piece.
you can see the doorway to the far right of the balcony.

SCN5122.jpg

as for the floor i did not have a shot of the underside of the balcony but what i can make out here is the pillars had a square crown on the top which i think was big enough that they extended almost to the edge of the molding. Then there is a filler piece between the moldings like the top of the balcony roof.

SCN5124.jpg

SCN5127.jpg
 
I finished the deadwood frame steps last night and this is the final result the light blue frames Z Y X W and V are double frames the numbered frames are single frames.

steps2.jpg
 
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