Hull Split Question

[RanSan]

Gentlemen, Most RC subs use a center split — usually a Z‑cut or an L‑cut — for internal access. I’m wondering why that’s the standard instead of fixing the bow and stern to the top of the mid‑section and having only the bottom of the mid‑section drop away. In theory, that would keep the top of the hull clean and seamless without the split line running across it.

I realize a bottom‑access design would mean flipping the sub upside down whenever you need to work on it, but is that really a significant drawback? Is that inconvenience alone enough to make the design impractical, or are there other reasons why this approach just isn’t typically used?


Randy

[neitosub]

I think it's perfectly valid. The only drawback I can think of with bottom access is when you flip the submarine over to open the hull, you risk damaging the delicate surface details on the deck. More of an issue with a WWII sub I would imagine, compared to a modern boat.

[He Who Shall Not Be Named]

Gentlemen, Most RC subs use a center split — usually a Z‑cut or an L‑cut — for internal access. I’m wondering why that’s the standard instead of fixing the bow and stern to the top of the mid‑section and having only the bottom of the mid‑section drop away. In theory, that would keep the top of the hull clean and seamless without the split line running across it.

I realize a bottom‑access design would mean flipping the sub upside down whenever you need to work on it, but is that really a significant drawback? Is that inconvenience alone enough to make the design impractical, or are there other reasons why this approach just isn’t typically used?


Randy

I did my first r/c submarine like that. Never again!

[trout]

You can do that, but think of how you are going to connect your wtc to the pushrods and make adjustments. Are you going to do that with the sub flipped over every time? David, what did you dislike about doing it that way that makes you say “Never again!”?
I have not done it this way before, so I can see issues but do not have actual experience.

[JHapprich]

I suppose one choses the wtc length according to the conditons of the specific model.

[He Who Shall Not Be Named]

You can do that, but think of how you are going to connect your wtc to the pushrods and make adjustments. Are you going to do that with the sub flipped over every time? David, what did you dislike about doing it that way that makes you say “Never again!”?
I have not done it this way before, so I can see issues but do not have actual experience.

That first (and I can assure you will be my LAST) boat to employ this bottom access was the very clean-hull AKULA. That subject has nothing to get in the way or get knocked off by inverting the hull and sitting its deck on a work-stand. You can imagine the nightmare of trying to avoid deck railing, guns, antenna runs and the like if the model features such detail bits!

And what a pain in the ass to access that model each time I had to flip it over for pre-mission, mission, and post-mission checks and adjustments.

All that trouble to avoid the one radial break in the hull halves at the upper stern of the model if the more reasonable Z-cut is employed.

Bottom access looks good on paper, but is a nightmare on the bench. DON'T DO IT!

https://youtu.be/2O8gTIr4lys

David

[Das Boot]

Listen to the pros.