Japanese Sen Toku I-401 Submarine Build

[Sinksalot]

Yea 1/72 is big when printing a I-400. I got a 1/48 scale IJN I-19 coming soon. Now that is a big sub 7 !/2 feet.

[Sinksalot]

Almost forgot this is a 1/125 test print of my I-400 design. I printed it to find errors in the design.

[redboat219]

How big would it be at 1/96 scale?

[cheapsub]

Full size 122M X 12M

1:96. 1.27M / 4.17ft long

Just a bit bigger than World War II Fletcher class destroyer

[rwtdiver]

I have re-sized my i-401 to a more manageable size!



It will work out to about 39" in length! I have all the bottom sections printed out, and I have a good start on the upper hull! Do to the size reduction, I am not sure if I can configure the stern section to accommodate rudder and stern dive planes linkage for full operation!

This may just turn out to be a static model! I will know more after I start into the actual build construction!

Rob
"Firemen can stand the heat"

[redboat219]

39 inches equates to 1/123rd scale.

"It's impossible, but doable." - Robert MacDougall (Sean Connery) Entrapment.

[redboat219]

Maybe you could try the components used onboard this 1/100 IJN Maru Yu transport sub with your I-400.

[redboat219]

The Maru yu used dual piston tanks for diving and pitch control, dive planes are fixed. Only moving control surface is the rudder.

[redboat219]

Dual piston

[Sinksalot]

Dual piston

Are those the piston tanks that use the lipstick case to push the piston in at out? If so, I always thought that was a great idea.

[redboat219]

Are those the piston tanks that use the lipstick case to push the piston in at out? If so, I always thought that was a great idea.

Wife: Honey, have you seen my L'Oréal Colour Riche Original Satin lipstick?
You: Nope.

[Sam Victory]

Dual piston

I've seen this video before and yes, it's interesting. The rc subs in the video are basically small, like 1/150 VII, 1/350 I-400, 1/200 IXC...etc. I forget if he uses a servo or something else to push the piston. The 1/72 I-400 was 179cm long, bigger than Engel's 1/100 Typhoon. WWII submarines always have a high freeboard, so I think a gas system (like SAS) is the best choice, simple, takes up less space, saves power, and allows the sub to break the surface tension of the water to come up to the correct waterline position. What you need to consider a bit more might be a very powerful diaphragm pump, like this one, with two pairs of air ports and drived by a brushless motor，very powerful.

One piston tank takes up a lot of space, not to mention two, and the real I-400 sub does not have a very good diving effect because it has a very small pair of bow planes.


Unlike the common 90-degree front planes retraction, the I-400's are 180-degree retraction, so for RC, it can be retracted by using a rack-and-pinion structure.

[redboat219]

Wat_air is currently converting a 1/350 I-400 to RC. If he can do it in 1/350 scale you can do in something that is twice bigger.

[Sinksalot]

Yea the one IJN sub I bought has that same system. Most likely made by the same person.

[Sam Victory]

I remember Mr. Bob Martin talking about his 1/32 XXI U-boat project in one of his youtube broadcasts (I forget the scale, it might be this scale), he used two ballast water tanks, one placed in front and one behind. Then someone asked why not use two piston tanks, Bob's explanation was similar to what I said, the piston tanks take up too much space and are too complicated, but that doesn't mean they don't work, it's just that the gas system is still better when applied to a situation like a WWII submarine. engel's rc submarines have always used piston ballast systems, no matter what submarine it is. It's their tradition and their patent, and they won't change it easily.