RC Submarine: Hull, sail and planes

The sub is based on the Dumas Akula kit, but I am only planning to using 4 items from the kit, as the rest is not scale true or are of a low quality. The 4 parts are:

• Upper hull
• Lower hull
• Sail
• Radar dome

The radar dome was however missing from the kit together with at few other items. Dumas was however kind enough to send the missing items.

As can seen from the photo, the hulls are very plain - no scribing at all, no marks for the flooding holes etc. All that must be added by you self. The tail of the sub is also too short, so I have planed to extend it 4 cm.

Hull

The hull is quite elastic and therefore needs some re-enforcement. At the same time I need some way to secure the WTC in the hull. For that purpose I have made some insert that will solve both needs. (More re-enforcement is however needed). They are made from 5mm acrylic sheet which is milled to shape as showed in the picture.

Top hull with most of the water holes, sail and radar pod.

Now it is time to re-enforce the bottom hull. I have added the WTC holders and made an re-enforcement in the bow, so the two parts will fit better together.

The little block with the hole in is a temporary block to make it easier to align the two hull parts.

Tail extension

The hull tail is too short, so I am extending it with a piece of plastic which is turned to shape.

Details

A few details has been added to the hull to make is look more realistic.

Painting

First the whole hull is sanded with grid 400 and then it is primed with an airbrush.

Then a temporary color while testing the sub.

And now the final painting.

Sail

The delivered sail has the wrong shape: the top should be water level and it should be tighter.

The water level is fixed by cutting the sail in a more flat line.The tighter is solved as showed on the picture:

Here is the finished sail (without any holes):

Masts and periscopes

I have made some masts for the sail which should be able to be raised and lowered from the transmitter.

This is version 2 of the mast which has now been painted. The main hull screw has also been painted. The painted mast are shown with its holder.

Rudders

The radar pod is taken from the kit, but is modified as the shape and height is wrong. I have also added a rudder to the pod as on the real sub.

The lower rudder is made from scratch and has a small reenforcement made from aluminium.

Well, the first try was to make the rudders from Plexiglass (as above), but after at few tests it was clear that it was not strong enough. I therefore bought a sheet of 3mm thick Duraluminium, which is twice as strong as normal aluminium and 2/3 of steel.

I made a little test piece of app. 6mm wide (and 3mm thick) and drilled a 1.6mm hole in it. I wasn't able to break it in my hands, so that should be strong enough!

I then continued to make the rear dive planes out of aluminium with help from the mill and some handwork- they are strong. I have made the active part slidely larger then on the 'real' sub to make more effective in the water.

Here is a picture of all the finished rudders:

The rudders are fastened and re-enforced to the hull by use of aluminium sheets glued to the hull.

Here all the rudders and tail is test assembled.

Here is the rudder control. The first image is how the attachment is made and the next it is actual rods.

Here the controls are mounted to the planes.

Dive planes

The front dive planes must be able to retract itself. Here is the mechanic for the movement. All parts are home made.

Motor shaft

In order to make the shaft runs more smooth I have inserted a ball bearing between the WTC and the propel. The ball bearing is sealed to avoid any damage from the water.