Ridge on Balao hull, what is this?

[Henk Freubelaer]

Hello all,

It is some time ago that I posted, but my Bowfin project is still going strong.

Currently I am adding the weld seams to the hull and I ran into a mysterie.
At about midship I can see a ridge on the lower hull, from pictures that I have of the Bowfin now there are more than one.
I am pretty shure that they where added somewhere after the war accept one.
In a picture of 1944 I can see one ridge, or at least I think it is a ridge.

Maybe someone can help identirying what this is so I can add it to my model if needed?

Thanks in advance.

The ridge as it can bee see'n on the curent Bowfin.



And the ridge as it shows in 1944

[RCSubGuy]

I'm no expert, but it looks like a simple overlapping seam of steel. In the first photo, there appears to be a similar one two sections forward as well...

[He Who Shall Not Be Named]

Masker-belts? (An element of the Prairie-Masker self-noise reduction system). An early 'test' arrangement?

David

[Henk Freubelaer]

Thanks folks,

I think you might be both right.

As someone else pointed out to me, that is where the rear bulkhead of the auxiliary balast tank is, as SubHuman pointed out there is also a ridge visible more to the front.
According to a cutout drawing I have thats the front bulkhead and it is indeed a bigger weld that is visible.
Apperently the skin plate of this tank was thicker than the rest of the hull.

As David pointed out it micht be a masker-belt that is running over this weld.
This might be indeed a experiment of that time, as how Bowfin is now there are more of those ridges and they are probbably added at the end or after the war.

Please correct me if I am wrong.

They are a mystery to me since I can not find them on pictures of other Balao sub's during wwII.