Fleet Boat propeller shafts - How were they set up?

[mermaid]

Im having a hard time getting good documentation on the Gato/Balao propeller shaft angles. I have measured a downward angle of 2 deg. relative to the WL from a plan of SS-238 Wahoo. However, I have only a hazy idea as to the lateral angulation W.R.T. the ship's longitudinal axis. Jeff LaRue has mentioned 3-4 deg. Mike Keating insists it was around 15 deg. Does anyone know what the true specifications were? There seems to be no problem finding side and top views but I not been able to find even one of the ship's underside.



Edited By Mermaid on 1143483112

[boss subfixer]

Mermaid,
I'm not sure of angles

Mermaid,
I'm not sure of angles and I'm not disputing Jeff or Mike but here is what I have. This is a view looking forward at frame 128. The dimensions are from the centerline of the ship to both port and starboard 5 feet 8 inches. The other dimension you need is this, from the molded base line or the bottom of the keel 6 feet 10 inches. This dimension should also work for the center of the stern planes since the center of the prop hub is located directly centered to the planes. As for where the shafts come out the hull you should be able to locate that from your plan, just make the hole a little bigger than you need to allow you to locate the ends of the shafts. When you have everything located just lock it all in with epoxy and build up the fairings for the shafts outside the hull. That is how I plan to do this when I get there.
Hope this helps.
P.S. you might want to concider making a fixture to help with the alignment.

[JWLaRue]

Diane,

If you are going to

Diane,

If you are going to 'quote' me, at least get it right. I did not say that I knew what the shaft angles were on a fleetboat. I said that I knew what they were for a Type VII and that though the fleetboat had angled shafts, I did not have any hard numbers. I did say that they looked to be more angled than in the VII....at least doubled.

-Jeff

[mermaid]

Dear Jeff]



Edited By Mermaid on

[color=#000000]Dear Jeff]



Edited By Mermaid on 1143727636

[mkeatingss]

Ok, folks here's some hard

[color=#000000]Ok, folks here's some hard data from BuShips.
From BuShips No. SS420-S0103-986287, Plate 2 and BuShips No SS385-S0103-986275, Plate 2]

[mermaid]

Dear Mike]http://www.subcommittee.com/forum/icon_question.gif

Dear Mike]http://www.subcommittee.com/forum/icon_question.gif[/img]

[boss subfixer]

Mike,
The dimensions I gave are

Mike,
The dimensions I gave are from the USS Cobia drydocking plan of 6' 10" and is probably an as built dimension. The difference of only 1" between our information tells me that there is a dimensional tolerence for the height from the base line. I'm refering to the difference between the Cobia (a Gato) and your balao specs. As for the Tench my guess is that was something else that was changed to maybe make the boat better. The more I think about it there may be another reason for the dimensions being different. There are two sets of drawings out there for the Gatos and Balaos (not sure of Tench) one by Electric Boat and one by Portsmouth Naval Shipyard. That could take into account the differences, but I'm seriously guessing here. Oh! the plans I have for the Cobia are the E.B. plans from the Wisconsin Maritime Museum plan # 2025-22.
Diane,
Baseline = the bottom of the keel or boat also refered to as the molded basline.



Edited By Boss subfixer on 1143587078

[mermaid]

Thanks Mike and Subfixer. Good

Thanks Mike and Subfixer. Good stuff! Right now, I'm at the very early stages of planning. I have yet to obtain a good set of plans. I'm aware of the plans available from Scale Shipyard. (Which ones should I buy?) How do I go about getting the planset you are referring to?

[boss subfixer]

Diane,
Try these two places.
http://www.wisconsinmaritime.org/reproduction.htm
http://www.floatingdrydock.com/T.htm
The first

Diane,
Try these two places.

http://www.wisconsinmaritime.org/reproduction.htm

http://www.floatingdrydock.com/T.htm

The first link you can get the drydocking plan from the USS Cobia. The second one has plans for several different boats. Just scroll down.
Use copy paste if the links don't work.

[tmsmalley]

Diane - I have a

Diane - I have a couple of items that might help you. Send me an email (president@The SubCommittee) with your mailing address and I will snail mail them to you.
Tim

[mermaid]

Thanks for all the help!

Thanks for all the help! I really appreciate all the great feedback. I think I'll go for the Cobia docking plan to start.

[mermaid]

It is interesting that there

It is interesting that there is a greater prop shaft divergence in the Tench class boats. I took a look at the specs on the NavSource Archive. It appears that the Tench class used the same arrangement of two motors per shaft geared together for a total of 2,740 shp. I know that at one point, the two geared motors per shaft arrangement was changed to a single direct drive motor for each shaft. Was this modification ever implemented with the Tench class and could this account for the change in shaft divergence?



Edited By Mermaid on 1143748526

[tom dougherty]

The Tenches were all direct

The Tenches were all direct electric drive, no reduction gears.

[mermaid]

Thanks Tom. It appears I

Thanks Tom. It appears I was partially right. What confused me was the fact that the shaft horsepower is identical to that of the Gato/Balao classes. I therefore assumed that the Gato/Balao drive arrangement had been retained in the Tench class.



Edited By Mermaid on 1143920307