Steam Ship Naparima by Kevin Kenny - FINISHED

[druxey]

Looking good, Kevin! One forgets that in certain parts of the world termites are a consideration.

[Jim Lad]

She's really looking the goods, Kevin!

 

John

[Kevin Kenny]

I have had to gas two of my earlier models that were being attacked by termites so now i treat everything. In more temperate climates wood worm can also be as destructive. A few years ago i did a major renovation at home using plywood from Brazil. 10 years later it exploded with powder post beetles. We had to rip it all out. It could not be treated.

[Kevin Kenny]

[Kevin Kenny]

[Jim Lad]

She's starting to take shape nicely, Kevin.

 

John

[Kevin Kenny]

[Kevin Kenny]

[Kevin Kenny]

Roof top, 76 -4” x 6” trusses 

[yvesvidal]

Time to sand the hull and prepare it for painting.....

 

Yves

[Kevin Kenny]

Yves

i still have a long way to go before i do that. I have a series of parts coming in two weeks. Not sure if they will work or are to scale. Once all the hull fittings are put in including the propellers and i see what works and what does not i will know how to finish. I actually have the plating  layout for the hull. I have not decided how i am going to simulate the plates as yet.

[michael mott]

The plating layout drawing is quite interesting Kevin, the shape speaks to the whetted surface area of the hull in a way that I had not considered before, and demonstrates why the sterns of classic racing yachts are the shape they are they have much smaller surface in the water apart from the fin.

The model is looking great.

 

Michael 

[Kevin Kenny]

I am sure there are some of you that have simulated metal hull plates. I am considering two options. One is to transfer the lines onto the hull and score the lines into the wood with an exacto  knife. The rivets will be simulated with dots of superglue. The other option is to cut paper  copies of the plates and stick these in the hull. The  Rivets will be the same as suggested.

[Kevin Kenny]

[Kevin Kenny]

Just got a beautiful copy of the original picture of the Naparima in the Thames river before sailing to Trinidad from the National Maritime Museum. 

Edited February 1, 2020 by Kevin Kenny
Spelling error

[Jim Lad]

What a great photo!

 

John

[G.L.]

10 hours ago, Kevin Kenny said:

I am sure there are some of you that have simulated metal hull plates. I am considering two options. One is to transfer the lines onto the hull and score the lines into the wood with an exacto  knife. The rivets will be simulated with dots of superglue. The other option is to cut paper  copies of the plates and stick these in the hull. The  Rivets will be the same as suggested.

using paper copies seems to me a good method.

[Kevin Kenny]

I have ordered these 3D printed air vents which are to scale. Hopefully they are what they say they are. If they turn out ok 3D offers the hobby  great possibilities. I have a number of friends that have 3D printers but no one is prepared to do the design work to get the pieces printed. I am thinking of learning some form of autocad so that i can do the design work and then send them for printing.

[Kevin Kenny]

Lining up the post. I was surprised that only a few had trouble lining up. Inner stanchions come on Tuesday with my daughter from New York.

[mtaylor]

Depending on where you ordered them from, the vents should be good.   More and more accessories for model ships are showing up in the 3D printer world.

[Bob Cleek]

On 1/31/2020 at 12:19 PM, Kevin Kenny said:

I am sure there are some of you that have simulated metal hull plates. I am considering two options. One is to transfer the lines onto the hull and score the lines into the wood with an exacto  knife. The rivets will be simulated with dots of superglue. The other option is to cut paper  copies of the plates and stick these in the hull. The  Rivets will be the same as suggested.

She's coming along nicely under Our Blessed Mother's watchful eyes, Kevin.  

 

If I were you, I'd use paper plates of scale thickness applied to the hull unless the plates were all butted and backed, rather than overlapped. I'd wet the paper where it needed to follow any tight bends and glue it with PVA and then give it a coat of shellac, making sure it soaked in well. You shouldn't have an problems with the paper plates coming loose if they are shellac-impregnated. Once the shellac is dry, the surface can be sanded as may be needed and getting a good paint job should be no problem.

 

It will take some experimenting, but you also might consider running a ponce wheel (which you'd have to make yourself to get the right spacing, I expect) over dampened paper laid on a slightly resilient surface. That might produce slight "bumps" that would simulate rivets well. I expect some types of paper would work better than others for this technique, but I have no idea which.

 

The first consideration is how she was plated. There are several styles, e.g. butted edge to edge with backing strips, overlapping belts, bent lapped edges, and so on. That will dictate whether plate seams can be scribed into the hull or overlapping "plates" will have to be applied. See: https://images.search.yahoo.com/yhs/search;_ylt=AwrUi2jUQzlej3kAdFAPxQt.;_ylu=X3oDMTEycGpnZHQyBGNvbG8DZ3ExBHBvcwMxBHZ0aWQDQjg0OTJfMQRzZWMDc2M-?p=ship+hull+riveting+patterns&fr=yhs-elm-001&hspart=elm&hsimp=yhs-001#id=35&iurl=http%3A%2F%2Fmodelshipworld.com%2Fuploads%2Fmonthly_02_2015%2Fpost-246-0-52774900-1424910653.jpg&action=close )

 

There are also different styles of riveting. It was not uncommon to see outboard below the waterline rivet heads countersunk to produce a smooth surface to increase speed and fuel efficiency. And, of course, the rivet patterns have to be accurate, as well. That would require some idea of the framing layout. Having the plating plan is a huge help there. I'd offer the observation that, more often than not, rivets are overdone. If they are done, they really have to be to scale or the hull looks like it's got the pox. This thread might be helpful: 

 

 

[Kevin Kenny]

Thanks Bob 

I have the riveting instruction (see attached) and also found a similar ship built around the same time but by a different ship yard that was restored But used a similar construction, so I plan to follow this. 

[Kevin Kenny]

[Kevin Kenny]

Lots of stuff just arrived 

[Bob Cleek]

Nice jewelry!

[Roger Pellett]

Kevin,  Nice work!  If you look up the thread “simulated rivets on plastic hull” on the forum, you will find my magnum opus regarding riveted hulls based on observations of surviving examples around the Duluth Harbor.  

 

Overall conclusions-  Rivets joining hull plating are barely visible since they were usually hammered flush into a countersunk hole.  This was necessary to take advantage of the hot metal of the rivet shrinking to produce a watertight joint.  Rivets joining topside structure are more prominent as snap rivets with domed heads were used to join light superstructure plating.

 

Roger

 

 

[Kevin Kenny]

Thanks Roger

 my gut told me that i was taking this too far. 

[Kevin Kenny]

Deck vents installed. Just the grills to put in each vent. Now for a breather as i am starting to do s,,,,it

[Jim Lad]

She's grown a lot since I last checked in, Kevin - very nice work indeed.

 

Just to reinforce Roger's comments, here are details from (old) photos of a couple of my old ships when in dock.  Although they are obviously much larger ships, you get the idea.  In the first one the hull rivets around the stern of the 'Sydney Breeze' are completely invisible to the eye from this distance.  In the second photo some of the rivets around the forecastle of the 'Thames Breeze' are visible due to the shadows caused by the strong light on white paint, but they're certainly still not prominent, or even really noticeable unless you're looking for them.

 

John

[Roger Pellett]

Kevin,

 

In my day the first fact that a beginning Naval Architecture student was required to remember was that a 1ft square x 1in thick steel plate weighed 40.8 lbs with all other weights in proportion.  From your plating expansion drawing your vessel is plated with 7-1/2lb plate with some 8-1/2lb plate on the bottom.  7-1/2 lb plate equates to 3/16in, very thin but not unusual in a vessel of this type.  I don’t know what scale you are building to but at museum scale of 1:48, 3/16in equates to .004in.  

 

Checking paper laying around the house cheap computer paper, .003in; letterhead correspondence, .004in; Crane 24lb acid free thesis paper, .009in.

 

I have a little experience with trying to plate a model hull, in this case a Great Lakes freighter hull.  I first drew a plating expansion diagram like yours above by taping the girth of the hull at various stations, and laid out the plating pattern based on photos of the vessel prior to launch.  Once I was satisfied I marked the plates on the hull using a wooden spline tacked to the hull.  So far, so good.

 

My next step did not work.  I tried to affix brass shim stock plates using 3M transfer tape.  A day or so later edges of the plates began to lift.  Frustrated, I put the model aside and worked on something else.  Today, I decided to try Bob Cleek’s paper and shellac idea.  I plated a prepared strip of wood with two weights of paper using bookbinder’s glue and got a good bond.  Tomorrow I’ll shellac it but am concerned that the alcohol in the shellac might attack the PVA glue bond.  We’ll see.  I was also concerned about peeling the brass plating off the model hull but it peeled right off.

 

Roger