Plans for ship's boats

[Boccherini]

I have need of plans for the ship's boats for my Harriet McGregor build, circa 1860. Can anyone suggest where I may obtain these?

 

Grant

[Jaager]

Check the plans for ship's boat drawn by Underhill at the Brown, Son and Ferguson web site.

I count 5 possibles -  about page 20-21

 

https://skipper.co.uk/catalogue/drawings-and-plans/page/20

[allanyed]

Do you know what kind of boats were on board, gig, cutter, launch, etc?  Same for sizes of each of the boats.

 

There are a number of drawings of ship's boats on the RMG Collections site as well as the Wiki Commons site, but it makes the search easier if you could search by type of boat.

I have no idea if the example below is appropriate but it is from the Wiki site and will give you an idea of what can be found.  Some of the plans are more detailed than others but most would be useful in building a model from the drawing.  Sone are in high res, others in low resolution.  Drawings on line at the RMG site are all low resolution, but can be purchased in high res if you find what you are looking for.  Scantlings from

W. E. Mays' book on ships' boats might also be useful even though the book is centered on warship boats.  Everything from futtock dimensions to thwart widths and thicknesses are listed in those scantlings.  Again, they are for ships of war boats and from circa 1800 but still may be useful to you.

Allan

 

 

[Roger Pellett]

Most of the readily available information about ships’ boats deals with warships.  Since you are building a sailing merchant vessel you are venturing into uncharted territory.

 

From the drawing that you posted it would appear that the double ended boat is a lifeboat and the other a workboat.

 

In this context, a “lifeboat” was a specialized craft designed to meet British Board of Trade regulations covering capacity, stability, flotation, and hull strength.  It could have been of either wood or metal construction.  If wooden, it would have been clinker planked.  Capacity, generally began with crew size, allowing 10 cu ft per person.  The regulations then specified  proportions, length, beam, and depth for each range of capacities.  You might begin by trying to look up Board of Trade Regulations on the Internet.  Old shipbuilding handbooks often publish lifeboat drawings.

 

For the workboat, a square sterned, relatively full lined wooden boat.

 

Roger

[Boccherini]

Gentlemen,

thank you all for your suggestions, I spent an interesting couple of hours poking around the interwebs.

A possible solution was found at the back of my copy of Underhill's Plank On Frame Vol 2. There are plans for 30 foot versions of both boats. The boats from the plans I'm using are both about 18' 6'' (full size). If I enlarge the plans from the book until they match the scale length I require, will this work? Or will it mess with the proportions? Would anyone notice?

 

Grant.

[Roger Pellett]

The book Ships’ Boats by Ernest Blocksidge (1920) lists the following proportions for lifeboats.  Dimensions in feet and inches:

 

Capacity (people).       Length     Beam.    Depth

16.                                  18.            6’-3”.       2’-4 1/2”

18.                                   19.            6’-6”.      2’-6”

 

Hope that this is useful

 

Roger

[Gregory]

10 hours ago, Boccherini said:

If I enlarge the plans from the book until they match the scale length I require, will this work? Or will it mess with the proportions? Would anyone notice?

What method are you using to enlarge them?

[Jaager]

The plans in the book are probably a much reduced copy of the 1/4" plans.

If the book illustrations are enlarged, it comes down to how much artifact is introduced and how much that bothers you.

The 1:48 plans just need a reduction of 0.8 -  plus whatever correction factor your home scanner requires- which you probably already know and used for the ship itself.

 

[Boccherini]

Roger,

thanks for those dimensions, kind of very helpful. Enlarging the drawings from Plank On Frame V2 to the correct scale length gives me reasonable agreement with the length and depth (if measured at the mid section from bottom of the keel to the gunwale), the beam is off by the equivalent of 1foot full size.

Jaager,

original plans were 1:96, printed and supplied from Brown, Ferguson...... They are not fantastic quality, probably having been copied from a copy of or the original, then creased, folded and stored for many years prior to my purchase. The life boat plans are reductions from the 1:48 originals.

Gregory,

I'm just using the copy function on my printer

 

thanks for your assistance.

Grant. 

[Jaager]

Way, way back   when I was just starting with this and Underhill was one of the few important sources for scratch builders - and he is still an important source - I bought a few of his plans.   They were actual blueprints.   They were blue lines on a white background and not the white lines on solid blue that was still common then.   The quality was so-so at best  - I do not imagine that the intervening years have been kind.  

Back then, there were not a lot of choices for scratch plans,   I think that the NMM was doing photography.  You sort of had to go in person to even know what was possible.

I have not been able to determine which class Underhill's 12 gun brig of 1840 belongs to.  He was probably accurate with his post 1860 merchant sail plans - an era that few NA have done much to compete with him even now.

 

I take scans into my raster based graphics program and do any scaling there - as well as cleanup and line isolation and print that for pattern use.  It also makes register and alignment points easy to add.  Greatly enlarging small scale plans also makes the lines wide and ambiguous.  Doing a tracing in a graphics program gets better lines for patterns.

[Roger Pellett]

Computer technology aside, there are engineering reasons why a boat design cannot simply be reduced. Simply put the characteristics that produce a successful design are not linear.  For example, displacement is a cubic function.  If dimensions are halved  displacement decreases by a factor of 8 (the new displacement is 1/8 that of the old).  Transverse stability is an exponent function of the waterplane, and so forth.

 

Roger

[Boccherini]

Jaager, Roger,

thanks for all your commentary, it has been informative and interesting. I'm not at the stage of needing the plans to do the boats, so I'll leave it for the present and let it rattle around in my head for a while.

 

Regards,

Grant.