Wood boat hull

[BOB BLACKSHAW 1Participant @bobblackshaw1]

[BOB BLACKSHAW 1Participant @bobblackshaw1]

Hello all,

I've made a 2/3rd scale A A Raymans marine steam engine, started on the boiler and now thinking of the boat hull. I made the engine 2/3 rd scale so it will be the same size as my other steam boat engine, and so can scale up to the same hull.

The hull on my steam boat is made out of a solid lump of wood carved out, so was thinking of drawing the shape and profiles out of cardboard as patterns. My question is if I had layers of wood planks under 1/2 inch cut out the rough pattern then glued the planks up, would the finished hull warp after it was finished. I've been looking for a sawn up log on my travels but seems a lot more work involved cutting out the shape.

Bob

[Bryan Cedar 1Participant @bryancedar1]

I would think that if the hull was constructed using glued planks ie, resembling plywood, there is less chance of warping as in proper plywoood. I have two hulls made purely for show constructed this way.

[An OtherParticipant @another21905]

Why not have a browse around the Model Boats site for some ideas and inspiration – go to the ME home page, and scroll right down to the bottom, the link is in the gray box.

[John HaineParticipant @johnhaine32865]

It depends on the wood. My father made me a model boat from a set of Hobbies plans based on a stack of cut-out horizontal laminations, must have been 1/2" thick I guess. He used offcuts of teak flooring from the place he worked which was having a posh new building put up. Used Casco wood glue. Never any problems with warping that I recall.

[BazyleParticipant @bazyle]

This is an age old traditional method of model boat construction called 'bread and butter' or 'sandwich'. You do keep the planks in line though not cross-plied. Thick planks, like 1 in, are less sawing though if you have a bandsaw or jigsaw it is a doddle. You can just get planks from a timber merchant but unless well seasoned and quarter grain will likely be bowed. This only matters for the bottom plank that is widest. You only need two planks if you are cunning and the hull profile is suitable. When you cut the inside out of the largest profile it can use it for the next but one layer and so on alternately. Some people have even managed to cut at a angle so it fits the nest layer.
Unless you are good at the carving this method can end up a bit thick & heavy but it is easier now with an electric sander.
It is also the method used with any old crap like MDF for making the mold for a glassfibre hull.
I would suggest you liook into a final outside single layer of glassfibre using fine cloth and epoxy not polyester resin to waterproof and strengthen it. Go to Modelboatmahem forum for more details.

[DalboyParticipant @dalboy]

For lightness and room the traditional method of plank on frame it takes a bit of time but well worth the effort. There are also suppliers of fibreglass hulls but finding one in the style and scale that you want may be difficult.

As above the bread and butter method can be done and by cutting out the waste from each plank before glueing will reduce the weight early on and save trying to carve the inside.

Which ever method you choose think about prop tube and rudder tube placement before starting as sometimes it can be easier to install these as you progress with the hull construction

[BOB BLACKSHAW 1Participant @bobblackshaw1]

Thanks for the replies, looks like I will go for the sandwich method on the hull, never thought of fiber glass on the outside for strength.

Thanks Bob

[Bob McParticipant @bobmc91481]

Hi Bob…

I am making a model boat at the moment, this is 'Ravenna' and plans are from a well known supplier, disclaimer,

I didn't plan to make a boat but was in the process of changing a wooden slatted venetian blind when it ocurred to me that the wooden slats could be used for something.

The 'slats' are I believe Maple and I managed to bend most of them to shape using plenty of clamps.

'Planks' are butted up with plenty of good quality waterproof glue, small gaps filled in with expanding glue and when finished soaked in thinned paint then 4 coats of paint,…still not finished this … but it looks ok having never had a go at a model boat before.

The cabin is now buit up and am making window frame inserts using brass 22mm compression olives which are elongated over a mandrel and silver soldered.

I don't know if this is the right way to go about it but I'm not one for convention…

Good luck Bob..

[BOB BLACKSHAW 1Participant @bobblackshaw1]

You have done a great job of the boat Bob, if mine comes out as good I will be happy with the that.

Bob

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