The Ship Model Forum

Ballasting will be a question for a while... again, I expect 59 lbs total displacement, but I'm not sure what the light boat will weigh, so I can't predict the ballast exactly. On top of that, this model won't fit in my bath, the water outside is hard, and I'm not planning on building a dedicated float tank! So I did my sums as best as possible, looking at displacement volumes section by section, estimated weights and moments about the CG, and then allowed for extra trimming ability. Knowing the density of lead (0.41 lbs/in3) and a spheroidal packing efficiency of about 70%, I can predict how much ballast volume is needed and where.
Translate that into lengths of PVC pipe, and I get a set of 1-1/2" ballast tubes- similar to what I first used in my 1:144 Yamato for easily removable ballast:
http://www.rcgroups.com/forums/showthre ... ost6944430

To locate them repeatably, chocks were built at several frames. Not as elegant as the "ballast cabinets" in my Dearborn tug:
http://www.rcgroups.com/forums/showthre ... ost9565724
but then that model is lighter and doesn't need ballast "removability"... and it's a darn sight nicer than bags of shot tossed in the bilges!

This pretty much concludes the interior construction portion of the show... I'll glue those chocks in and varnish the insides, then it's on to the deck, bulwarks, and glassing the outside.

ok, one more little detail... if you install platforms in the bottom for your hardware, add little pieces on the sides to catch the little screws and things which are otherwise magnetically attracted to inaccessible regions...

Pat she is really taking shape there. I really like the PVC tube idea for ballst tanks as they nestle nicely in the hull.
I would like to know what you are going to use to finish off the outside of the hull? What type of resin and matt etc...
Thanks.....Greg Knipp

Thanks Greg.
Outside- my usual, epoxy plus one or two layers of 2 oz cloth.

Let the decking begin!

Actually, a pretty simple task, using 1/8" ply. But avoid any temptation to deck the whole boat at once, even if your sheet of ply could cover everything... camber and sheer will conspire to foil such an attempt. In the first shot, two strips of ply have been laid down-- the small pieces make the fitting job a lot easier. Also, each piece is trimmed back 1/16" from the side to form a rabbet which will accept the bulwarks, to be made of 1/16" ply. Blessedly, the bulwarks on this boat are everywhere vertical, not inward leaning which so greatly complicates things.

But first I'll cover the ply deck with resin (no glass needed over ply...), and sand that smooth to be my steel deck. I was thinking of "plating" the deck with sheet styrene, but the resin coated wood will be a stronger substrate to glue the bulwark supports to.

Then I'll lay in the bulwarks and their supports, followed by glass on the outside which will reinforce the bulwarks to the hull. Can't wait.

OK, I knew this was a LARGE scale model... but while waiting for the first coat of resin to dry on the new deck, I sat down and listed all the bits and pieces needed as details. Not so many, because it's just a little tug... but BIG!

• Cowl vents are 1 inch across
• Wood ship's wheel is 3.6" on the rim, 4.4" across the spokes
• Life rings are 3" OD
• Deck cleats are 1.6" across the horns
• Nav light lenses are 1/2" OD x 5/8" high
• and it goes on...

Still, I'll take that over 28 sets of triple 25mm AA emplacements any day...

OK, I'm fickle... wavered on whether to sheet the deck with styrene, decided to go for it. Entire deck is covered with 0.010" styrene, as are the bulwarks inside. Obvious advantage of not needing to seal/sand a lot of wood for a "steel" look, though I did put a coat of epoxy on the ply deck first. The sheets are glued on with beads of CA laid over the scale deck beam positions. The glue's thickness telegraphs through the plastic, so this way it looks ok. Also, after being out in the sun, the deck will take on a scale "oil canning" look, works great.

The bulwarks are made from 1/16" ply, except around the stern where two layers of 1/32" let me get around the curve. On the real boat, only 12" high forward and 5" aft, or 1.2" and 0.5" in 1:10. The ply fits nicely into the rabbet at deck's edge, and the assembly is very strong even before applying the bulwark braces. Braces are also styrene for a clean paintable finish.

Sheesh.. u are going so fast every time i check the forum there is a new page!! i got a small portion my deck layed on my ship in the time it took u to do all that

Looking good Pat. Dropped mine off at the Lake Pontchartrain Basin Maritime Museum. Great Museum and getting better.

http://www.lpbmaritimemuseum.org/

Thanks all, and congrats on that, Rmay.

Time to put on the fiberglass.
I did a once over the hull, sanded a few details etc., then cut out a piece of glass to fit one side. Books have been written on glassing (I know, I wrote one... ), so I won't belabor it here. Position the glass and daub on 5 ounces of epoxy... while waiting for that to set enough to trim, I think I'll have lunch... and maybe back to the drawing board, need to figure out how I'm going to build the ship's wheel and a few other details...

I needed a break from sanding my fresh 'glass, so started on the ship's wheel. The rim is easy... need to turn the spokes and fabricate a hub... and a steering stand and binnacle...

And I now declare and end to major dust making operations.
Doesn't mean I don't have a lot more other stuff to do for a while!

OK, it may seem like nothing much has been happening for a while... but I've put on and sanded 2 coats of glass, eating up several sheets of sandpaper, destroyed my shop due to the dust, vacuumed every square inch of surface area as a consequence, and now have moved on to rub rails.
I wish I could have sanded outside, but that below zero stuff put the kibosh on that idea. I did use a face mask, but my jitterbug sander is totally unapologetic about spewing the dust in every imaginable direction... sort of like a vacuum cleaner exploded inside the shop!
So after the sanding and then making the rub rails (1/2" half-rounds, which involved a new router table and some table saw work), I stood down and washed up. Took half the day. Tomorrow, I bend rails onto hull! Then prime, sand, fill, prime again, etc etc.

They all seem to look the same, till you put on some paint, you will see a big difference between a good job and a bad one, keep up the good work,

Hi, I'm new here and this topic convinced me to become a forum member. Congratulations, the build quality of your hull is superb!

Some might know me from other model forums where I use the same name and i seem to recognise some names here too, so hello to everyone!

The tug has rub rails made from split 4" pipe (about 5" OD), so I used the router table to round over the edges of a 1/2" board, ripped those off on the table saw, soaked them in ammonia, and bent them to the hull. These are big pieces of lumber, and that's no easy task! That's why I haven't come up for air for a while...

They're pinned to the frames with 2mm dowels and a few bottles of CA. A little more work before I seal them up, and then it will be on to the first coats of primer.

But also need to put the cap rails on the bulwarks. These will be built up from thin strips and then sanded and sealed.

Patmat,
I have gone thru your build log several times over trying to absorb your techniques for my next build, a 1/20 steam powered Clyde Puffer which will translate to 51" X 13.5".

Several questions:
1) Can't see clearly, but are you using 1/4 in. ply for your keel ?
2) Do you butt joint or overlap joint the 'futtocks' for your formers ?

Appreciate your help.

Dave

PATMAT wrote:Now it's time to start planking!

Dave-

The keel is 1/4" poplar (i.e., wood of convenience...).

You should be able to see the overlapped futtocks at the previous post:
viewtopic.php?f=13&t=38687#p254446

in the drawing and the part.


Pat

Here's the final effort on the tug's wheel, about 4 inch diameter.

Took some more time out from sealing/sanding the rub and cap rails to start building the towing bitts (short attention span, I guess...).

Bitts are turned from PVC rod, and are about 1 inch in diameter. Set into the framework in the deck with 1/4"-20 screws with nuts from below. Steel cross rod, and the gussets are plywood, to be covered with styrene. The gussets will be glued to the base, so even with the screw fastening, the bitt won't be removable.

Since these bitts will be used for real towing, the gussets couldn't just be butt-glued to the bitts... so I rigged a "milling" setup on the lathe to machine grooves to accept the gussets. Rock solid.

Hi ,

what I always have had wondered, is why on US tugs, there are almost never quick release towing hooks .

I now know that those tugs most of the times never "tow", but prefer to take the load ( boat , barge , whatever ) alongside instead of astern, hence the name "tug" , I guess ...

a lot of those tugs went to Europe during the war, and stayed there , but the first thing the european towing companies buying such tugs did, was to put a quick realease hook

Regards ,

Laurent