Building a work boat or lifeboat using a mold

[Kevin Kenny]

It has long baffled me How many of the great modelers make such superb work boats  That service the sailing ships of old. I had made many attempts but always felt that the finial product fell short of the Main ship model. One day i came across A post that suggested that these magnificent miniature  boats were made using a mold. I looked everywhere to find a paper or video to help me try but never found a complete process. So i decided to try to develop the process and recorded my work on video. The first one did not pop out of the mold but the second one did. The finial product was great if i may say so myself. 
Attached are the tree videos on the project. 
 

Part 1

Part 2

Part 3

 

[bruce d]

Kevin, well done. Untill I watched I didn't 'get' the decision to use a master with grooves cut in, or for that matter how to make the grooves. Now I get it and clearly it is a good way to produce identical boats.

A couple of questions, if you don't mind. (They will not make sense to anyone who hasn't watched the video)

Once the ribs/frames were in place, you sanded them down. I get that and of course this was possible because the ribs were supported in the grooves in which they were sitting, but still I wonder how you went about the sanding without overstressing the already small pieces. Hand held sanding block? Rotary tool?

The PVA release agent looks like a good find, well done English (see the video to decipher that message). If I am hearing your dialogue correctly you say that it left a residue: is that correct? Does the residue peel off or does it perhaps soak in to the wood which may affect later finishes?

Thanks for taking the time to produce the videos.

Bruce

[druxey]

When I first made open boats, my molds were made with grooves for the frames. I realised later that I didn't need to do that: I simply built the planks, edge glued over a plain mold. After freeing the shell, I bent in the frames (this is at 1:48 scale). Works just fine and saves a lot of work. Clinker boats can be built in the same way. The only critical points are:

 

a) The planks must be accurately spiled

b) the fit between strakes be really tight in the case of the carvel hull

[allanyed]

I am with Druxey in not using grooves.  They tend to be graves for errant frames if you want to place the frames first.   I make a similar mold shaped to the inside of the frames, then glue tiny spacers to keep the frames in place.  Holly is great for the frames as a minute soaking in water will allow them to be bent without splitting (95% of the time).   Couple photos to give you a better idea of what I mean.

Allan

 

[Kevin Kenny]

Its wonderful to see this conversation progress. My only wish is that it was not posted earlier which would have accelerated   my learning curve.
alan

I will continue to use the groves as they help line up the frames. The spacers are an excellent idea which should match the groves That were cut in the keel. Of course you could  probably make a keel without cutting the  groves to take the ribs.

Bruce

the ribs went through the building board and were stuck with white glue. Supported by the groves they were very stable which allowed me to sand as aggressively as i wanted.  For the fine sanding i did use the  Proxxon pen sander which is so gently its like painting with a brush. 
 

the PVA mould release was easy to peal off. English said i could use water to clean up but i did not have to. 
 

the only change i would make is to draw lines on the building board to space an drill the holes more precisely. I used the mold to determined where to drill these holes and they were not all 100% accurate. 
 

i suppose that in time i may not have to use the groves but for now it provides me with a fool proof way of lining up the ribs. With the second one there was no issue of it coming out of the mold. It just came right off.

[druxey]

Sure grooves help align the frames, but my 'aha' moment came when removing a boat and half the frames stayed on the plug! Had to glue them into the shell anyway.

[tkay11]

2 hours ago, allanyed said:

I make a similar mold shaped to the inside of the frames, then glue tiny spacers to keep the frames in place.

Great idea! I wish I'd had the thought of using spacers before. Thanks very much, I'll definitely do that in future.

 

Tony

[Tom P.]

On 5/15/2020 at 8:54 AM, allanyed said:

I am with Druxey in not using grooves.  They tend to be graves for errant frames if you want to place the frames first.   I make a similar mold shaped to the inside of the frames, then glue tiny spacers to keep the frames in place.  Holly is great for the frames as a minute soaking in water will allow them to be bent without splitting (95% of the time).   Couple photos to give you a better idea of what I mean.

Allan

 

 

Those a very fine models.  They are beautifully crafted and all the better for being historically accurate. I'm in the process of building the Model Shipways HMS Bounty Launch kit - my first wooden boat model - and I'm a little dissatisfied with the kit.  There are significant differences between the kit and the reconstructed launch in the National Maritime Museum in Cornwall. I've been searching for information about how these launches were actually built and when I saw yours I thought maybe you were using the Museum's reconstruction as a pattern.  Or do you have other sources of information for it? Another question, if you don't mind: Your model launch has the windlass for handling the anchor, just as shown in the Draught from the Nautical Maritime Museum, Greenwich, which was the basis for the Model Shipways kit.  But doesn't that kind of heavy work also involve things like bollards and fairleads/sheaves?  The Draught shows none of those, but it is a schematic in some ways.  Maybe these launches left the shop in various configurations to fit the ship to which it would be assigned? Or are some details just lost to us?