PLease help me decipher these plans

[Guest]

I've scanned my USS Hardhead plans and corrected them for scale and distortion. Okay, so far so good. I'm at the scribing and drilling stage, having at the hull penetrations, manhole covers, etc. Here's the thing - I can't figure out these two structures and how to represent them on the big Revell Gato. The notations on these plans are just blurry enough to be unreadable in some areas - as luck would have it, the areas I'm interested in! Ever have one of those days?

The first image shows two oval structures with circles within just forward of the starboard shaft. I'm assuming these are drain holes for the main ballast tanks and they should be drilled out completely. But, if that's so then why the circles within?

The second image shows a square structure below the waterline and perhaps one-third of the way up from the MBT openings. How should that be represented? As scribed lines or as raised weld lines?

Many thanks for any help. I would have used the excellenet Paddle flood and drain template on this site, but Hardhead's pattern is just a bit different.

Robert

[mkeatingss]

Drawings

I'm not sure what the Circle & Oval things are, but they're not Flood Ports. Check the notes, on the drawing. I'll keep trying to find clearer drawings in my stuff. But it may take awhile. I have, somewhere in the area of, 20,000 drawings on my HD. Some, really good, some useless.

The thing in the blue drawing appears to be a sea chest. The outer rectangle would be a slightly raised weld bead. The smaller , inside one, would probably be a grating.

But without frame numbers, as reference, I can't be sure, on either drawing.

If you just want to talk, you can reach me at <<Mkeatingss(AT) cox.net>>.

Mike K.

[ricknelson]

The oval/circles ARE flood ports.

The oval/circles ARE flood ports. The ports are for #7 MBT. The plans are identifying two different versions depending on hull number. Try to read which hulls had the circular cutouts and which had the oval cutouts.

The rectangular hole is a seachest for Main Motor (not engine) cooling water (intake or discharge). You should cut it out but then put in some kind of screen or instead, drill an array of small (1" at 1:1) holes inthe rectangular area.

The Hardhead, SS-365 is a Balao boat built at Manitowic so it's based on EB plans. Check with the Floating Drydock web site under the "Bu" listings. Tom put in some Balao plan sets. Look for the "Docking" plan, it will give you all the hull penetration info you need.

[ricknelson]

Does the document have a

Does the document have a table listing all of the hull openings? If it does, refer to the numbers adjacent to the holes in question and look those numbers up in the table. It will give you a very brief description, position, and size.

[Guest]

Thanks for the help, guys.

Thanks for the help, guys. The plans are from the Floating Drydock. They are quite nice except that the lettering is just blurry enough that its hard to read anything but the largest letters. I was able to do some work in Photopaint, removing noise, moire, sharpening here and there... I can make out the word, "Flooding Holes" and then an SS- listing for hull numbers that could be 364-370. I can't quite tell. Some letters are still obscured. It could be that I'll need to go with the circular openings, if my cleanup of the image is accurate.

The second image does have "Sea," as the first word of the description but rest is illegible, so it could well be a sea chest. If you don't mind me asking, what is a sea chest? Sorry, but I'm ignorant of some nautical vocabulary.

The only EB Balao-class docking plans at the Floating Drydock are for the Becuna in a postwar step sail configuration. Would those work? I would think that she would have been so refitted that perhaps not.

Thank you both for your help!

Robert

[ricknelson]

The words "seachest" refer to

The words "seachest" refer to an opening that is similar to a box with the open top facing outboard. A pipe of some usually large diameter is in the bottom of the box feeding something internal. The seachest insures that there is a large reserve of water for the internal machinery to draw on. Some kind of screening or an array of smaller holes are over the top to keep large objects from entering the pipe.

The Becuna Docking plan should work fine for locating hull openings. They usually didn't change that much unless the hull was lengthened.

[Guest]

Thanks for the info. There's

Thanks for the info. There's a lot I don't know!

The good news - there are a number of references to SS-313-315 on these plans. Since Perch II, Shark II and Sealion II were the first Electric Boat Balaos, it makes sense that they just shipped their plans to Manitowac, their follow yard, for the first few Manitowac Balaos. That would explain why I'm seeing a lot of the same C&R blueprint serial numbers from both EB and Man. on these plans. I'm going to order the Perch expansion plans and hopefully they will be clearer and more legible.

Robert

[Guest]

The Perch expansion plans came

The Perch expansion plans came today, and they spell out everything in super detail. They are the Hardhead plans (or, perhaps its the other way around!) and are very clear and readable. The sea chest is labeled as "sea suction," so its certainly the same thing.

It seems to me that someone wanting to build an early EB/Man Balao could use either set of plans and mix and match where needed. It looks like Perch II, Shark II, Sealion II, Hardhead and Hawkbill were identical in nearly all respects, using the same plans. Variation only started after each yard gained experience with the heavy hull. Their decks were different, with EB using a full length wooden deck and Manitowac the partial wooden deck, but otherwise, they're pretty much identical.

I also obtained the early Gato expansion plans for another later project, and they're likewise wonderful, even spelling out hull penetration differences between SS-212-216 and SS-217-219. There were differences even within this first series of EB Gatos.

Gentlemen, thank you again for your time and help. Now, its off to work on the big fresh water sub!

Robert

[ricknelson]

A good set of references

A good set of references makes detailing a boat a lot of fun. The docs are well worth the investment. Good luck and enjoy your efforts.