Double-planking, or not? (Moved by moderator)

[MarkBseau]

Why are some models double-planked, some not?  Is this for historic accuracy, or to get a better finish?
I can well imagine wooden sailing ships being double-planked for strength - for that matter, might some have more than that?

 

Is it assumed that you'll double-plank a hull when the instructions don't say anything about it?  Or will a kit always supply enough wood for a second planking and discuss it when that's supposed to happen?

[russ]

Many times, a kit has too few bulkheads in the framing to really define the shape of the hull. This is one way the kit manufacturers can keep the cost down to make the kit affordable. The result is that you need that first layer of thicker planking to help strengthen the hull and better define its shape. Otherwise you end up with flat areas developing in the wide spaces between bulkheads in certain critical areas of the hull. The final planking is done to get the look of a single planked hull.

 

It would help to know which kit you are dealing with. Some are single planked, others double planked.

 

Russ

[testazyk]

Hi Russ--I haven't bought a kit in a while but I remember that they usually indicated "double plank on frame" or less commonly "single plank on frame."

 

I don't know for sure why there is a difference, but I for one am deeply grateful for double planking.  I find hull planking the most challenging part of ship building and it's great to be able to make mistakes in the first layer, fix them with sanding and putty and then put on the second layer to hide everything!  That could well be a reason they do it.   

 

All of the double plank kits I've done make it very clear which is the first and which is the second layer.  The first layer of planks are generally thicker and a lower grade of wood (e.g., pine) while the second layer is finer (e.g., walnut) with nice grain and colouring.

[MarkBseau]

Thanks for the replies.  Russ asked what model I was dealing with - for one, I have Dumas' G. W. Washburn waiting for me to get some more experience with simple stuff first.  It doesn't seem to mention single or double-planking, and that's one reason I asked the question (wondering if it was just a "given" that we double-plank).

 

So it sounds like when double is called for, it might be a different wood (or perhaps different widths?) used?

It also seems like you would completely ignore the pattern of planks in the 1st layer when doing the 2nd, is that right?

 

Sorry for being completely ignorant, but - er. well - I am...

[russ]

In double planking, the first layer is thicker for strength. The second layer is really for appearance and is usually thinner. When doing the second layer, you can follow the pattern of the first layer or not. It really depends on your preference.

 

Russ

[testazyk]

Hi Mark--

 

Have a look at this--looks like it's single planking and this might give you some good ideas:

 

http://modelshipworld.com/index.php/topic/186-george-w-washburn-by-larry-dumas-1890-tugboat-148/?hl=washburn

[augie]

You might want to contact Larry who has completed this kit.  I'm sure he'll be happy to comment:

 

http://modelshipworld.com/index.php/topic/186-george-w-washburn-by-larry-dumas-1890-tugboat-148/page-2

[MarkBseau]

Yes, I've seen it - what a great job he did on it!  (I've asked him about the 'beard' fender he hung on the bow.)

 

Now, my question is "why" it's a single-planking.  Is this basically because a tug ought to be a painted finish, which would pretty much hide all that work anyway?

 

Thanks,

Mark

[Beef Wellington]

Mark, I think Russ hit the nail on the head.  Models that are designed to be double planked typically come with a limited number of bulkheads that give the shape to the hull-far fewer than would be on a real ship.  Because there is a reasonably large distance between these, its very hard avoid having peaks and valleys no matter how well bulkheads are fared.  Smoothing out the first planking and covering with a second layer makes up for this deficiency.  I don';t think its down to skill level, its inherent in the structure.

 

Kits (and scratch builds) that use a significant number of bulkheads or frames have a much smaller distance between them which allows a modeler to simulate the original ship using single planks, as each one can be given a much better lie to each plank.  On the double plank hulls you sometimes see builders simulating with shaped balsa filler to provide extra shape to the hull, typically at the bow and stern where the lines change most significantly.  Of course this method of building is more manually intensive to get the frames correct.

 

Of course, in both of these methods, it ultimately comes down to the skills of the modeler on how good a finish they can achieve - its never guaranteed.

[mikeaidanh]

Panart's Armed Pinnace is triple planked! If that was not enough the first planking is effectively the inner face of the model which means care must be taken from the start. The second planking brings some relief as it will not be seen and simply adds strength. Finally the third layer and much more care needed. In the end you will have a very strong hull with a large proportion of the "bulkheads" removed to form the open boat that you are building. The planking was a pain in the fundament but the end result well worth it.

 

Mike. 

[wq3296]

Greetings Mark,

 

I haven't been impressed with any of the previous attempts to answer your question since there is not one definitive answer. I built a relatively high end kit from Corel (Berlin) that has widely spaced bulkheads and is single planked with thick walnut intended to be left natural. Once the hull was planked, she seemed to be as solid as any other model I have ever built. I have also built several high end Blue Jacket and MS kits that are single planked in basswood over widely spaced bulkheads. These kits call for painted hulls. In my opinion, strength is not the primary reason for double planking, since practically any configuration of hull construction will produce adequate strength. Frankly, how much strength does a static ship model need? I am familiar with construction of wooden boats, and most are single planked. From what I've read, most early ship construction relied on one exterior layer of planking, although there was an inner layer applied to the inner face of the frames in some ships.

 

As you know, many models of early ships are double planked, with the outer layer being of thinner mahogany, walnut, etc. The obvious and only reason for this is to simulate the look of the actual ship. However, if the ship is of later vintage and had a painted hull, in my opinion, there is no need for double planking. Further, I see no compelling reason for double planking since a hull can be singled planked with wood intended to painted or left natural. With that said, I think a double planked model would be better for a beginner because it is easier to plank over a planking that is used as a base for the thinner, outer planking. It all comes down to skill and how the ship should look when completed, and not strength or any other hocus pocus.

 

wq3296