Calling all "41 for Freedom" SSBN fans

[Walt]

I served on The 601 (RE Lee) and she was originally named Shark. These were not Literally cut in half Skipjack hulls. They were Skipjacks redesigned with a bird farm on the drawing boards. However the 601 finished he career as a SSN. One of the SALT treaties made her and her Polaris A-3s absolete..Good boats the 598s were.. Fast..

[aptivaboy]

The Floating Drydock has plans of the Lafayette in their TFW range. No idea of quality. If they're like their Ohio-class plans, which I have, they're likely more basic. The Ohio plans did have frame callouts but were nothing like the long defunct and missed Deep Sea Design plans of the Ohio and various SSNs.

Bob

[Maarten Sch�nfeld]

Thanks, Bob!

Here a picture of my Boomer family as it stands now, with all the required mods.

[Tom Dougherty]

Nice work on the modifications.

[aptivaboy]

Are there any reviews of the Micro-Mir Lafayette/Franklin/Kamehameha class SSBNs? I'm thinking I'd like to get one, but would appreciate any pointers on their accuracy. I'm more interested in the basic shapes and dimensions being correct. A lot of sins can be covered up with some putty and sanding, but the basic shapes and dimensions need to be correct.

Many thanks,

Bob

[Maarten Sch�nfeld]

but the basic shapes and dimensions need to be correct.

Hello Bob,

Length and width of the hull of these kits are correct within a mm or so, the tapered shape of the forward and rear of the hull seems close enough to the naked eye when compared to the official drawings. Same is true for the sails and the upper hull casing with the missile tube hatches. Only quite some putty is required to blend the forward upper casing with the hull.

The errors with these kit lie in the horizontal and vertical tail surfaces, both in shape and dimensions. I need to make some more detailed sketches to explain the errors maybe, but the drawings published earlier in this thread provide clear reference. Basically, the width over the horizontal surfaces should be 40 feet.

Also the fairwater planes need refinement, their rounded corners should be square. Finally, the PE metal propeller provided in the kit is a very poor representation in my opinion, but I can provide you with a much better example.

Is this a good review for a start?

[aptivaboy]

Thank you, yes, that's perfect! I can probably CAD up and 3D print some control surface replacements when time allows.

Bob

[Maarten Sch�nfeld]

Hi Bob,

Then I like to add a few more characteristics I noted: the horizontal surfaces (dive planes) of all the USN nuclear subs, beginning with the Permits and through to the Los Angeles class, and also including the '41 for freedom' boomers all had the same basic size and shape: 40 feet width (or 'span' if you are more into aircraft), straight rear edge and 30 degrees backward angled front edge.

In case of the MikroMir Lafayettes and Franklins the forward edge is angled too sharply and needs correcting. Also, the dive rudder hinges are 2 mm too far forward: I solved this by adding a .080 x .080 Evergreen square rod insert after the fixed portion, and removing a similar amount from the dive rudder.

The Franklins have end plates attached to the top and bottom, these are markedly different from those in the Sturgeon class: these are single endplates added to the outside of the dive planes. For the Franklin class you need to study how the 'horn' of the dive plane is arranged, as it needs to provide sufficient room for the end plates.

In the MikroMir kit of the Franklin the end plates are missing, and studying the dive planes will reveal that there is no room at all for them. This triggered me to restructure the dive planes, and in retrospect I had to do that also to the Lafayette and my own Ethan Allen class conversion. These look much better now too.

As for the vertical rudders, the kit provides rudders that are more or less right for the Lafayette (and Ethan Allen) class, but watch that the rear edges of the upper and lower rudders are not exactly lined up. For the Franklin class the upper rudder needs to be reduced in height, but that was described above in the thread.

[Vepr157]

Good detective work there Maarten!

A while ago I did a comparison between piping TAB drawings, photos, and the kit, and found that the sail was very out of shape. I 3D printed a significantly larger sail with a flatter top designed by using the drawings, and it seemed to match photos very well.

[Maarten Sch�nfeld]

Detail of the dive planes of my MikroMir Franklin. The Lafayette and Ethan Allen planes are similar, but lacking the end plates.

[Maarten Sch�nfeld]

Good detective work there Maarten!

A while ago I did a comparison between piping TAB drawings, photos, and the kit, and found that the sail was very out of shape. I 3D printed a significantly larger sail with a flatter top designed by using the drawings, and it seemed to match photos very well.

Hi Vepr,

That's very interesting! Could you please post pictures of the new sail, together with the kit version, pointing out the differences?

And: are the 3D prints of your sail available for sale or otherwise?

Maarten

[Vepr157]

I don't have access to my models right now, so I can't show you the difference. All I did was scale piping TAB drawings (that are already on this thread I think) to 1/350 and made a simple model in Inventor which I then printed out. The real sail is longer, taller, and the top is sharper/flatter instead of the almost semi-circular top of the kit sail.

No, I can't offer anything for sale.

Jacob

[aptivaboy]

I might be able to CAD a new sail up, but give me a week or two to look at the plans. I'm also about to start my summer job and dealing with a very sick kitty with cancer, so while I plan on doing these sails, I don't want to commit without clearing my plate off first, so to speak.

Bob

[aptivaboy]

Floating Drydock plans ordered. I also have an old BWN Daniel Webster kit in the stash to check anything I cad up against. I seem to vaguely recall that Mike Bishop served aboard the Webster so I tend to think that he would have made "his" boat as accurate as possible. Does that sound accurate or was I imagining things?

Kitty is still with us, thank fully. She has bone cancer but seems stable right now so I might have a tad more time. Given the choice between cad work and a family member, the family member comes first but I will get done what I can, when I can. No ETA on when the plans will arrive.

Bob

[aptivaboy]

Okay, the plans are here. I'll start working on the sail tomorrow. They only have little outlines for where the masts go, not actual drawings of the masts themselves. These are among The Floating Drydock's more basic TFW plans (not meant as a knock - I'm sure there was and remains little about these boats that isn't restricted in one form or another when they were drawn), so what are everyones' thoughts about the masts?

Bob

[aptivaboy]

The plans are definitely a tiny bit rough, with the plan and profile showing slightly different lengths for the sail. Hmmm....

[aptivaboy]

Okay, how does this look? I want to get the rough shape down before hitting the details. Also, should the sail have a flat base or a slightly curved base? The plans show a curved base but as I don't have the kit in front of me I thought it best to ask. As soon as the basic shape is deemed accurate by you all, and you guys who served aboard these boats would know best, I'll open a new thread in the Virtual Modeling section of the site. The filet around the top of the sail is also hard to determine in the plans and photos. Is it rounded enough or should it be rounded more? It looks okay to my eyes, but again, best to ask.

Bob

[aptivaboy]

Does the side profile look okay? This came straight from the FDD plans. I know that the top needs to be filleted more, but is the side profile acceptable?

Many thanks,

Bob

[Maarten Sch�nfeld]

Also, should the sail have a flat base or a slightly curved base?

The curve is dependent on the hull: in the Ethan Allen class the sail is located at the curve towards the bow, so the rear is horizontal but the forward edge is some 8-10 inches lower than that. In the Lafayette/Franklin there is hardly any curve at all in my opinion, as the sail is located further aft relative to the bow. Again, if any, there is only a slight curve at the front end, a few inches at most.

In 1/350 it is negligible for the Lafayette/Franklin, but for my Ethan Allen I had to add a sliver of about 0.5mm at the front to avoid a gap. In any case, the front of the sail should be vertical relative to the datum line.

Is the top of the sail to your liking? In my view it seems too angular, and should be more rounded, both in side view and cross section.

[aptivaboy]

Working on it. The FDD plans show the Lafayette's lower sail profile as rather curved, so perhaps they exaggerated that lower sail to deck curve?

Sorry the images have vanished. Photo bucket is acting poorly. I may need to find a new image hosting site.