1/12 Seehund build - LWB

[SubDude]

For three years I used just that kind of 'test tank' Great price, and just big enough for models under 40" in length. Mine eventually succumbed to UV and had to be trashed. Now, I can't find any in the stores in town!



David

I don't have anything under 40"...

[SubDude]

Ha, that looks very familiar. I must be finally doing something right!

Yeah, the one I got was the biggest possible size and I had to call around a bit. Found one near Milwaukee and another one in the container store in Chicago. They had just one.

The real fun part begins after the test: Getting all the water out. When full it is too heavy to lift, so I have my own technique of using a big pan to get it out. At the end of the exercise the shower is as wet as the operator. :)

What does it weigh ready-to-run?

[tifosi12]

Nice looking boat by the way. I like the paint job.

Thanks! My first time at airbrushing (the rust color).

[redboat219]

David

Is that one of those 3D printed S80?

[He Who Shall Not Be Named]

Is that one of those 3D printed S80?

No. GRP, resin, and metal kit that Bob bought from Mike Caswell -- originator is Small world models, Dave Manley. It's a 1/96 OYASHIO test shot I put together for myself when I was involved in upgrading the SWM line of submarine kits for Mike, then later Bob Martin.



David

[tifosi12]

What does it weigh ready-to-run?

Haven't measured it yet. The 3D print is fairly light, I'd guesstimate about 2.5 kg. We'll see. So far I have only measured the lift force of the styrofoam and the weight of the ballast. They're somewhat equal.

Next time I have it all together I'll measure. Right now it's in bits and pieces again trying to squeeze in the foam somewhere.

[tifosi12]

What does it weigh ready-to-run?

3.2 kg with the torpedoes

Why were you asking? Just curious or is that number relevant in some way?

I bet yours will be over 10 kg.

[tifosi12]

Time for some more buoyancy tests in the tank, this time with the torpedoes. Actually my second and hugely improved set of torpedoes: they behave a lot better re: buoyancy than the previous set. These things are tricky as they are so low and far out, they can easily tip your boat either direction. But now that I have a much better idea on how much and where to place the styrofoam, hopefully the next test goes even better. Threw in some atmospheric lighting for fun. It is tricky however to place foam in a boat with such a narrow tail.

[SubDude]

Looking good! If the torps are an equivalent volume and neutrally buoyant they shouldn't negatively impact the trim on the sub should they? Maybe I am thinking too much in a perfect world.

[tifosi12]

Looking good! If the torps are an equivalent volume and neutrally buoyant they shouldn't negatively impact the trim on the sub should they? Maybe I am thinking too much in a perfect world.

I made sure they were built identical, same size, same PLA, same printer settings etc. They both float just enough yet once attached the boat lists dramatically.

I think I need more lead and definitely more cow bell. :)

[tifosi12]

More tank trials. Finally got the buoyancy nicely trimmed. Also the mechanicals seem to work just fine. Still struggling with water getting into the SD. No idea where it is coming from. Other than that she is ready to take on a bigger pond.

[tifosi12]

Notice the newly added external tanks. First I didn't want to bother with them but as I was struggling with a lot of weight at the narrow tail end, I realized that those tanks would be a great place to stuff some styrofoam. And that idea worked, boat is now lying even in the water and goes down and comes up pretty much horizontally. At least in the tank where static diving is the only way to test.

[SubDude]

How much water is getting in the SD?

[trout]

Still struggling with water getting into the SD. No idea where it is coming from.

I understand wanting to get it out in the open water, but if it is leaking, work through finding the source. I highly recommend talking the time and frustration to correct it, so, is it front or back that water is accumulating (assuming water can’t roll from one end to another).

[tifosi12]

How much water is getting in the SD?

Enough to shut the electronics down. Let it dry overnight. Today I'll see what survived.