Rattlesnake - a semi-kit Hahn model

[Greg Davis]

This class-offering certainly will have similarities to Dave Steven’s exposition on Sir Edward Hawke; but it will also have noticeable differences. With respect to hull construction, Dave created laser cut components to build many of the Hawke frames. Here we will stay true to the Hahn method – building sistered frames from strip stock. Full masting and rigging is also planned for this model.

I will be working from the semi-kit that is made available at The Lumberyard for Model Shipwrights. To help guide the construction of the model there are several Harold Hahn documents that I will appeal to. In Dave’s thread on Harold Hahn it was made exceedingly clear that beyond Hahn’s modeling and artistic skills, he also was a prolific author!

Some of the Hahn literature that I find useful for this project include:

Ships of the American Revolution and Their Models. In this book, Hahn provides basic construction information on 6 ships and detailed information on creating a model of HMS Alfred. While Alfred is a much more involved model than that of Rattlesnake, the techniques involved are basically the same.

Rattlesnake, a 20-Gun Privateer. This article was published in the Nautical Research Journal Vol 39 No 1. You can also find a link to the original typed manuscript within Dave’s thread on Harold Hahn. In this article, Hahn talked about choices he made in creating his plans and model. Some pictures of the model were printed in the article. Interestingly, a full set of plans were published as part of the article.

I will also be making use of a collection of photographs of Hahn’s Rattlesnake model that can be viewed at https://www.modelshipbuilder.com/img/models/rattlesnake.pdf

Harold Hahn drew his plans based on drawings made by Howard Chapelle, George F. Cambell (who produced plans for the Model Shipways Rattlesnake kit), a model of Rattlesnake that was held by the Smithsonian, as well as Admiralty drawings.

Chapelle noted that history of Rattlesnake was vague, but that she had received her first commission in June of 1781. In 1782 the ship had been captured by the British and renamed Cormorant. At this time the Admiralty drawings were made. Apparently, the ship was renamed Rattlesnake in 1784. This information was all gleaned from Hahn’s article in the NRG.

It was this photograph of Hahn’s model that hooked me quite a while ago:



An order was placed in 2017 for the semi-kit. It has been on the shelf for a while and now it is time to get to it. A very interesting aside – The Lumberyard has NOT increased the price of this product; it now cost exactly the same as in 2017!

 

[Greg Davis]

Below is a list of what materials are provided in the semi-kit. What makes this a semi-kit, is the inclusion of several sheets of laser cut parts.As you can see, I chose the Swiss Pear timbering set.




The supplied wood is nicely bundled and identified to match the content list.



Here are the laser cut sheets:



An important part of building in the Harold Hahn method is having an assembly jig to position frames. Such a jig - laser cut - is supplied:



Finally, a full set of plans in the scale of 1:48 (i.e., 1/4" = 1') is included - rolled / no creases. There are 6 sheets in total - including masting and rigging information.



What you will not find is an instruction manual. This is where the material referenced in my previous post will quite useful.

In Hahn's descriptions of how he constructs his models, the starting point is typically the assembly jig. Here that is already done. Next he tends to build the stem-keel-stern post - deadwood 'backbone' of the model. This is then followed by fabrication of frames.

So as not to take up anymore bench space than needed initially, I have decided to go straight to fabrication of the frames. How this is to be done will be introduced and/or reviewed in a forthcoming post.

 

[Greg Davis]

Following Hahn's exposition on Alfred, I constructed a jig to cut pieces needed for the frame blanks associated with frames 4 thru 28.



The slots on the left are used for the 'top' layer of the frame blank; those on the left for the 'bottom'. The top extensions are rectangles and require just one cut in the jig (assuming the strip being cut has been cut perpendicular at the end). The other pieces are trapezoidal and need appropriate angles cut on each end. The two top slots on the right side of the jig are for cutting the piece that has the most extreme angle. First the shot slot is used to cut the lower (less extreme) angle. The strip is then inserted in the second slot to cut the piece to its final shape.

The jig itself is based / copied from Hahn's work. A piece of 1/4" Masonite was cut wide enough so the saw blade would reach both edges depending on which slot the miter gauge was positioned in. The Masonite is screwed to the bottom of a piece of pine, that in turn is screwed to the miter gauge. A 140 tooth 7 1/4" hollow ground saw blade was mounted in the table saw. Each side of the Masonite board was then cut. Copies of the frame blank components were made, each cut as needed and rubber cemented to the Masonite. Here it is important to get the edge angle perfectly aligned with the board! Next, using band saw and scroll saw, the slots were cut out. The jig was done. Jigs for other frames will be made later.

The strip framing material that was provided in the Rattlesnake timbering set is 1" wide. From what I can gather, Hahn like to work with stock cut to 7/8" - the plans themselves measure out at about 13/16". So I've set the jig slot with to 7/8" while maintaining the correct length of pieces as well as angles.

A couple of framing strips were ripped down to 7/8" and the jig was tried out. Below are the resulting pieces laid over the plans. To keep the pieces in each layer from moving around during the glue up, Hahn had rubber cemented the pieces of each layer to a copy of the frame blank plan. The two layers were then set on one another to arrive at the correct overlap position. He then drilled several holes thru the blanks to accept shot pieces of lil pins - these were used to maintain alignment when the layers were glued together. I get why he did that as these trial pieces don't want to stay where I set them!

 

[AnobiumPunctatum]

I wish you a lot of fun during your build.

 

[JacquesCousteau]

Very interesting build, looking forward to following along!