Bulkhead installation

[Schaye Goldcwaig]

Hello, I am currently building a Model Shipways Niagara, so far all has been so good but I have some doubt regarding the bulkheads.I dry fitted the bulkheads, and all looks fine with all the lower parts matching the bearding line, I draw the reference lines on all the bulkheads and all those lines also match with with the reference line I draw on the false keel.But later I saw that even with a good and alligned dry fit with all the reference lines alligned together, some of the bulkheads over lap a bit on top of the false keel.I know that the top of the bulkheads are curve a bit on top of each, which is normal, but that over lap is a result of the piece being laser-cut?
 

It is that ok?, and later once all the bulkheads are glued should I sand all the bulkeads on the top so the top of the bulkhead is flushed with the top of the false keel, but also keeping the curved shape on each bulkhead?

 

Thanks, Schaye G.

[Captain Poison]

I would take the measure of where should rest on the false keel and cut instead of placing it and lowering the excess on top, I think it would be easier.

Edited April 20, 2020 by Captain Poison

[Schaye Goldcwaig]

Thanks for your reply, so in my case the bulkheads must be installed in a way that lay flush with the top of the false keel and keep the proportion regarding the bearding line.I also have the concern if by follow your advise at the end those references lines will be affected as so for the installation of the bulkheads and a result effect on the kit?

 

Thanks, Schaye G.

[amateur]

Could you please post a picture. I have some problem in getting the picture, and am afraid to advise you in the wrong way.

 

Jan

[Schaye Goldcwaig]

Hello amateur, as you can see in the pictures if I place a bulkhead down on its slot to be flush with the top of the false keel, then the reference line relationship and aid between the false keel and the bulkheads are in some way lost, and I believe that this could affect the rest of the building specially the parts around and over the bulkead timberheads, but if I place a bulkhead down on its slot and alligned with the respective reference line of the bulkhead and the false keel, there is a small amount of curve part of the bulkhead that get over the top of the false keel.So, which is the correct way to install the bulkheads in relation to the reference lines and the top of the false keel?, If I install them by the reference lines, then later I will have to sand that small part of the bulkheads above the top of the false keel?

 

Thanks for your help

Schaye G.

 

The kit is a Model Shipways Niagara 

[Jaager]

If the line that is on the center spine and on each of the moulds is from the kit mfg, that is the reference/register line to assure that the moulds align properly.  Not only is the shape of the hull, and the run of the planking dependent on this being correct but the top is what replaces the deck beams.

The moulds look to be sparse enough in number and far enough apart that two layers of planking will be needed.  This means that the bottom of the moulds must be well above the rabbet for the actual planks.  Some ships had a garboard that was twice the thickness of the bottom planking and the outface was dubbed/adzed smooth and some had a step down.

 

If the outer planking comes in too high, a wedge shaped plank at the spine can fill the gap and allow the outer plank to seat in the rabbet.

Edited April 20, 2020 by Jaager

[Schaye Goldcwaig]

Thanks Jaager for your response.In fact with the bulkheads mounted with the reference line alligned with the spine or false keel reference line, the bottom of the bulkheas are well above the rabbet, as on the pictures.

 

The reference lines are from the kit plans.

 

So, once installed the bulkheads in relation to the reference lines, I should not touch the curvature of the top of each bulkhead or should sand them to make them flush with the top of the spine or false keel.

 

Sorry for asking again this, but I am still unclear in this step.

 

Schaye 

[Jaager]

Let me first supply this caveat, I have never built a POB hull. In deed, I went to some effort to demonstrate an alternate method to POB to fabricate a hull that gets you the place where the real planking of the hull can begin.  I jumped in because when I looked at C. Poison's pix of POB components and saw no lines to site the moulds properly on the spine, that shocked me.  Your model does have them.

 

But I do not believe that the height of the central spine has anything to do with the deck.  It would be more or less useless to have one line of pseudo carlings at the center.  Indeed, has it exists, it is a problem for hatches and masts.  It is neigh on to impossible to have the mast below the main deck be long enough to easily get the correct rake.  It just does not extend to a mast step on the keelson.   You do want to test that height and camber of the moulds will support a sweet and proper run of deck planking.  Use a wooden batten to do this. ( I am guessing that your deck is a sheet of basswood, instead of actual planks.  But even this does not like misalignment and dips. ) 

[Schaye Goldcwaig]

Thanks Jaager for the info.I will check.

 

 

[Dr PR]

Schaye,

 

The tops of the bulkheads must align with the sheer (fore/aft curvature) of the deck. If they do not your deck will have waves in it. You may end up having to sand the tops of some of the bulkheads, or maybe add strips to the top to bring a bulkhead up to deck height. This isn't uncommon in kits. You can use a strip of wood laid down lengthwise to the ship on the tops of the bulkheads to detect any that are high or low.

 

You will also have to sand the outer edges of the bulkheads to get the correct bevel for the planking. Again, attaching thin strips of wood or plastic to the bulkheads along the length of the hull will reveal if any are too wide or too narrow, side to side (port to starboard). Look down the length of the strips and if you see any "waves" along the length a bulkhead is either too wide or too thin.

 

You must get these things right before proceeding to hull or deck planking.

 

Also, be sure that you do not create any curvature in the false keel as you fasten the bulkheads to the keel. Check to be sure the keel is straight as you add each bulkhead.

Edited April 22, 2020 by Dr PR

[Schaye Goldcwaig]

Dr PR Thank you very much for your words, now all is more clear, so I can continue with the building of the model ship.

 

Schaye 

[Bossman]

Schafer, you have been given good advice. I have never built a kit that did not need some “adjustments” of some kind. As DrPR says, if a bulkhead is high at deck level, sand it down. If one is low, add a strip of wood to it. Same goes for the outside. Once you start fairing the hull bulkheads, if one is low, add a strip to it. Use a strip of plank and check your work often. Go slow. Trust me on this one, I’m the world’s worst at going too fast. Above all, have fun. 

[Schaye Goldcwaig]

Thanks Bossman for you comment.

 

Schaye