Considering the poor armor quality of IJN, just 0.2 units of belt and as much bulge as you can fit without losing a knot should suffice, to provide you with a fair amount of torp protection.

Did you make a mistake with your SY's base speed and put in 26 here, instead of 25?
I don't see how you can achieve that base speed with a full crew, unless it's very under levelled and thus very very light.

Don't use a ship until at the very least all your sailors are within 4 levels of reaching the ship level. For a SY (lvl 103 ship) that means you should aim to have all crew be lvl 99 or above before you start thinking about using it.
If you have lower lvl crew, go back to the ship where that sailor doesn't get an exp penalty for using it.

And Benser has it right for the armor.

Bulk does nothing usefull for the weight it costs and a SY can't carry enough deck to stop anything worth mentioning so you're better of not using it.

And looking at a ships DP/health bar to see if a targets ship armor bounced the shells or not, is a very bad way to judge that.
A BB4/5/6 can be hit for 30 k in 1 salvo, yet it will hardly show a dent in the health bar.
If you don't know why, Soft Defense read up on it.

If you want to see if a ship bounces shells or not, look at the damage numbers above the target. If a BB 4/5/6 gets hit by big shells and the damage numbers are in the hundreds, those shells are hitting fully. Only if those damage numbers are 0's or in the tens is the armor actually bouncing shells.

oh!!!!!

finally i got it!!!

thank you very much, benser and danita :)

Nikon,


   Fill your crew up with Engies and Repairmen.  Engies to give you more overheat time and speed, repairmen to fix the ship up when the ship has taken the SD damage, before it becomes real.  

    Even though the IJN BBs can't take hits, they are the best ships in retreating.  You want speed so if you do get pounded you can escape before being destroyed.  If you lose your entire ship's DP in the SD hits, then the ship takes full damage.  Also understand, smoking ships are still losing damage because of previous hits.  The nice thing about IJN BBs is they have the highest firing angles.   A good IJN BB driver will launch high lobs while retreating.  The enemy BBs will run into the shells while the IJN BB stays out of range of their shells.  Its tough to do, but a good IJN BB player should be able to beat any other equal BB 1 on 1 as the IJN BB shells hit hard and they can outrange other ships if you can hit them at the higher angles.