Question on waterline placement

[_SalD_]

Hello all,

 

I am fairly new to this website and I am currently in the process of building my first ship.   I am working on the New York pilot boat, ‘Phantom’ by Model Shipways.  I have carved the hull attached the keel and was getting ready to copper the bottom of the hull.  Before starting the copper I need to scribe the waterline along the hull.  To do this I wanted to build the Launching Ways that the model is displayed on to get its correct position.  Now, if I build the Launching Ways per the directions included in the kit the angle of the Launching Ways will be approximately 3 degrees, which will be the angle that the keel will sit at.  However, if I measure the angle of the keel from the plans that also came with the kit, that angle measures 4.5 degrees. Please bear with me a question is coming.

 

                                                          My cad drawing of the Launching Ways

 

                                                                Profile of ship from kit plans

 

 

Now I assume that the waterline on the ship should be horizontal when you have the ship on the display.  Yes? No? Doesn’t matter?  If so, do I build the Launching Ways per the kit’s directions and use that angle (3 degrees) to scribe my waterline or do I use the angle from the plans (4.5 degrees) and build the Launching Ways to that angle?

 

I’m leaning towards using the angle from the plans (4.5 degrees) and reworking the Launching Ways, unless that’s totally wrong.

 

I have one more question if you will allow me.  I was planning ahead and I've noticed that the angles of the two masts are not quite the same.  I don’t know if I’m being too precise here or are the two masts just parallel to each other?

 

Thanks for any help you can offer.

 

[trippwj]

Hi, Sal - good question!  I have also posted a response to your build log.

 

In this case, it appears that the ship sat lower at the stern than the bow - not at all uncommon for these types.  Increased speed, supposedly, as well as providing the rudder more bite and increased stability.

 

The launch ways are angled to allow the ship to slide into the water - think of them in relation to the ground and the keel is parallel to the ways. 2.5 to 3.5 degrees was very common for launching ways - about the ideal slant to let the vessel slide in a controlled manner into the water, but not so much that she would start to move before the blocks were removed.

 

The waterline is in reference to the way the ship will set in the water and will not match the slant of the ways.  In the water, the stern would be lower, hence that 4.5 degree angle as opposed to the ways.  They are really two totally different and unrelated sets of angles.

 

the masts also showed different amounts of "rake" - in general, the fore mast had slightly less rake or angle than the aft (main) mast.  This was very common across nearly all ship types.

[_SalD_]

Wayne,

 

Thanks for the answers and as I mentioned on my build log I will mark the waterline on the hull using the cradle I made that keeps the keel at roughly the slope shown on the plans (4.5 d.) and use the kit plans to build the launch ways (3 d.) and in this case when the ship is displayed on the launch ways the waterline will not be horizontal.  Hope I'm not over thinking this.

[wq3296]

Greetings Sal,

 

I see you are from Connecticut. I'm from RI. In my opinion, Wayne's answers are absolutely correct, and I couldn't add anything to them. 

 

wq3296

[Modeler12]

To me it would seem that the ship should definitely be 'horizontal' for a static display.

In other words, if the keel should be at some angle from horizontal, fine. But the masts etc should reflect the required set with regards to vertical. If the plans call for a waterline, stick with that.

BTW I don't go by angles for those small ones. Use the tangent or rise per linear dimension of the horizontal.

 

It is a bit like pictures of the sea. If it is slanted a bit, it looks like water should be draining towards the down side. I always correct pictured because of that (including those that have nothing to do with the sea).

Edited May 15, 2014 by Modeler12