The Ship Model Forum

When I get a bit further on (ie. having a hull under construction) I'll start a new thread. As my next project , ARL 12 which my dad served on off Okinawa, I have already some components to work with as it will be the same scale as the APA. I already have the assigned LCVP's, and 20 mm Orlikons that I need. Here is a first printed effort of the bow tub which was placed on the inclined part of the main deck above the bow doors. As with many 3D items, some minor mods needed. The 40 Quad is one of the APA early rejects but added in for effect. The new item will include the shield as typically seen on Battleships, sights and a few other minor improvements.

I do have the FDD plans for Sphinx, but fortunately I have my dad's photo album from which I can discern the WWII configuration.

Tom

Again, to quote my antecedents "Wah Hail". As you can see there is an external expression where the tub deck is, due to the deck shrinking and pulling a waist in to the cylinder. Brilliant repeat idea is to print the deck as a separate carefully sized element to slip into from below. Except the insert is a bit small after it shrinks. I could re size and reprint the deck disc, but easier to measure and use the vinyl cutter to make an appropriate sized disc from Strathmore cardstock to glue to the slightly small disc top. Works quite brilliantly! Then of course the resized from 1:196 Quad Bofors turned up to be 8% too small. Resized and re printing now. Otherwise the Bofors was nice looking (eye of the beholder).

To reiterate, 3D printing isn't a press a button and get a part operation, lots of experience (bad parts) by iteration in some cases.

Cheers: Tom

Very good print and design!

You are making a lot of progress Tom as the weeks go by!

_________________
Pascal

•Battleship Bretagne 3D: https://vu.fr/FvCY
•SS Delphine 3D: https://vu.fr/NeuO
•SS Nomadic 3D: https://vu.fr/tAyL
•USS Nokomis 3D: https://vu.fr/kntC
•USS Pamanset 3D: https://vu.fr/jXGQ

Thank you Pascal!

Here is the tub printed as an open cylinder, avoiding the waist distortion. As mentioned the base section I cut out and printed as a separate piece was a bit small due to shrinkage. I cut out the disc in a larger size using the Silhouette machine and laminated them for rigidity. It now fits nicely in the tub. Te Strathmore is finished with several coats of auto primer, which in my current experience holds up perfectly for at least 1/2 century. I also printed the ladder to the Mk51 separately so as an error in this fragile item won't ruin the whole assembly.

Tom,

Those parts look really good. I think (as we've both discussed) that flat objects such as tub floors, deck pieces, etc. do not tend to print flat or will cause attached or surrounding parts to distort. As I mentioned, my raised 5" mount platform for the LSM/R needed a solid wood brace below to hold it's flat shape and then cracked and had to be repaired. I can still use it with some modifications.

My 40mm tub printed ok but it doesn't have an extended circular wall as yours does. While your Strathmore paper floor will work, I wonder if you printed a tub floor and then measured the finished diameter to see what percentage of shrinkage had occurred and then reprinted adding that percentage to the design to compensate. If this worked you could then add the additional mount location rings, etc. into your tub floor design. Just thinking out loud

Hank

_________________
HMS III
Mocksville, NC
BB62 vet 68-69

Builder's yard:
USS STODDARD (DD-566) 66-68 1:144, Various Lg Scale FC Directors
Finished:
USS NEW JERSEY (BB-62) 67-69 1:200
USN Sloop/Ship PEACOCK (1813) 1:48
ROYAL CAROLINE (1748) 1:47
AVS (1768) 1:48

In general on my printer the part is printed 0,3 mm larger than the one drawn. It seems to be constant.

I take this into account on both parts when making an assembly.

_________________
Pascal

•Battleship Bretagne 3D: https://vu.fr/FvCY
•SS Delphine 3D: https://vu.fr/NeuO
•SS Nomadic 3D: https://vu.fr/tAyL
•USS Nokomis 3D: https://vu.fr/kntC
•USS Pamanset 3D: https://vu.fr/jXGQ

Admiral Daniel V Gallery (famous for capture of U-505) visiting ARL-12 on it's return from the Pacific, San Diego

Yes-T'dy ( a measure of time passage in my second favorite South Pacific nation ):

ARL...

Printed a test bridge structure (the front of which is seen in the photo above). Showing the bridge, chart house, radio shack, vent room and First Luff's office. In addition i have printed 16 deck ventilators (not helpful for Covid) which I suspect when I start placing them on deck, there will be several times more.





The whole pilot house affair was too long for my printer platen so the 1st Luff's office was printed as a separate piece.

Tom

Tom,
That looks really great! Did it come out to scale as expected? I think you did a really good job on the bulkhead details - nice to be able to add those items into the initial design where possible.

Hank

_________________
HMS III
Mocksville, NC
BB62 vet 68-69

Builder's yard:
USS STODDARD (DD-566) 66-68 1:144, Various Lg Scale FC Directors
Finished:
USS NEW JERSEY (BB-62) 67-69 1:200
USN Sloop/Ship PEACOCK (1813) 1:48
ROYAL CAROLINE (1748) 1:47
AVS (1768) 1:48

Tom,

Is this for the APA or ARL?

If it is for the ARL you really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really, really should start a new thread for the ARL!

Otherwise no one will ever be able to find the ARL information - or LSM - or BB63.

Phil

_________________
A collision at sea will ruin your entire day. Aristotle

As to DP's remarks, It is not necessary for anyone to read these posts and it is not necessary for me to post either. I more greatly respect the opinions of people who are actively creating and sharing projects and technique. Projects with too infrequent a post period go stale and are often passed by. My major object within this thread is to share my exploration of my journey into new types of scratch (No commercial parts) building. I have re done many of the APA pieces and will continue to do so. That some other current minor deviations (going back to upgrade older models) go on here merely lets one see how the various methods I am exploring are tested and vetted.

Cheers to the model builder out there.

Tom

Tom,

The pic you posted with Admiral Daniel V Gallery for ARL 12, the bridge venturis are huge.

With the horizontal bar running mid height across them, makes me wonder if the upper part was for the
bridge & and the lower half helped ventilate the deckhouse.?.

Best,

Paul

They are huge and seem to be a bit unique to these ships. I haven't seen any evidence that these were used for ventilation, but anything is possible. The mid section in front of the pilot hose seems a little blocked, which might be to keep the potholes more clear of spray? These were not fast ships, so perhaps the large size is to make up for reduced velocity. The ones for the flying bridge are also quite large. The flying bridge was probably a very pleasant place to con the ship from in typical Pacific conditions. I have a photo of the Captain and bridge crew in the uniform of the day (bare chested). In later days (post war) such ships as were retained as for support of the Brown Water Navy or electronic warfare (Sphinx) had the flying bridge glassed in. It's what the Royal navy dismissed as "Iron Ships and Wooden Men"...

Regards: Tom

Venturis were not used for ventilation. They collected air blowing against the front of the superstructure and forced it to blow upward along the front of the open bridge. This created a "wall of air" that deflected the wind blowing directly over them upward.

They work by capturing the moving air in the wider opening between the venturi and bulkhead at the bottom and compressing it in a narrower gap at the top. Reduced volume generates higher pressure (Boyle's Law), and higher pressure accelerates the air. So the air coming out of the top of the gap between the venturi and bulkhead is blowing fast and hard straight up. When this hits the wind coming horizontally toward the bridge it deflects the air stream upward.

This really works. My first ship, a small inshore minesweeper USS Cape MSI-2 had venturis on the open bridge. I have stood behind them in gales with 30-40 knot winds and rain, and the wind on the front of the open bridge was just a breeze. Most of the rain was deflected over the bridge. But we were also taking green water over the bridge and standing in 6-8 inches of water sloshing around the decks, so the venturis didn't help much to keep us dry!

The ARL venturis don't look overly large to me.

Phil

_________________
A collision at sea will ruin your entire day. Aristotle

Paul and Phil:

Here is another view of the bridge wing venturis taken during Rear Admiral (newly promoted) Gallery's visit. There is a bar stock used possibly for reinforcement but more likely to rig an awning. In front of the pilot house there is a "reducer" that restricts the volume, possibly to reduce spray on the bridge windows or flying bridge. I expect perhaps an "add-on".


These three ships were all at Okinawa and played their parts in the dance of amphibious invasion. There were 39 ARL's constructed, a decently large class though 10-39 were somewhat improved from 1-10. The APA's with their huge raft of boats simply weren't up to keeping them all in service with their relatively small facilities. The ARL's had extensive facilities from wood, steel crafting, engine overhaul (including a dynamometer). The idea for the fleet that came to stay was to replace shore facilities. RL 12 mostly hung out in Buckner Bay and Kerama Reto repairing and supporting the mosquito fleet. She was fitted with several distilling plants to be able to fulfill needs of her clients. By the time the invasion wore on diet was a lot of powered potatoes and powdered eggs with a side of powdered milk.

Though the ideal gas laws are the basis, what we see here is an example of the "Venturi Effect" such as we see in a carburetor where we get an acceleration of the air and a reduction in pressure. This is the same effect that generates a great deal of the lift of an airfoil as the airflow is accelerated over the top of the wing at a positive AOA with the resultant drop in pressure (generating lift).

Tom

So far I am just making small bitts and pieces which could go on lots of different WWII ships. Here they are getting a coat of a very flat black primer. Somewhat of the disorganized chaos of a real shipyard (in my experience). I did pick up a 2'x4' sheet of 1/16" plywood from which much of the hull will be built. The starting move will be to rip it lengthwise on the table saw into a 5" wide strip from which the main deck will be built. A narrower piece for the flat bottom and tapered pieces for the main sides. The rest should be enough for the ribs.



Tom

Wha Hail!

An expression commonly heard form my midwestern rural antecedents... Zo... Should I go back and replace my analogue " Double Track Gravity Davits" and boat winches with improved ones since developed technique wise in the Poseidon construction? Some precedent exists, I already replaced the laboriously hand constructed LCVP's, Bofors and Orlikons? Fortunately the Anchor winch and chain is well hidden under the forward Bofors structure.

Like I said at the start.... Tom

I did make replacement boat winches, using the ones from the ARL which as far as I can tell are the same models. Here you can see the old model on the left and the more correct one on the right, analogue vrs 3D. 3 of the 4 replaced, have to move the somewhat large and heavy model to access it.

Tom,

Nice improvement on the winch! Its amazing how much detail we are able to get using the 3D designed parts - like a whole new ball game.

Hank

_________________
HMS III
Mocksville, NC
BB62 vet 68-69

Builder's yard:
USS STODDARD (DD-566) 66-68 1:144, Various Lg Scale FC Directors
Finished:
USS NEW JERSEY (BB-62) 67-69 1:200
USN Sloop/Ship PEACOCK (1813) 1:48
ROYAL CAROLINE (1748) 1:47
AVS (1768) 1:48

Thanks Hank:

The new winch has the blessed characteristics of taking up less precious deck space. I have replaced a lot of original analogue bits and pieces, every weapon, Orkilons on their third iteration, Bofors and 5" second, boats second, and on and on. Alaska had every weapon except the main battery, including directors, replaced as did Missouri all the 5" and associated directors.

Cheers: Tom