| One of the main features of battleships is their large guns. The part describes the techniques used to construct the nine 16" guns | ||||
| Stage
6 First make some templates out of card from the drawings, then transfer them on to the 80 thou plastic card. Then with a sharp blade and straight edge cut them out and lay them in position for assembly. The first thing to check is the base of the gun, make certain it is slightly larger than the mount it sits on, otherwise it will not turn when you want to rotate the guns for display purposes. |
 Base and sides to be glued together |
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 Sides and compartments in place |
Having checked that everything is okay start to assemble the armour plating. I first glued the inside piece in position with Humbrol Liquid Poly, then I glued the two front side pieces, followed by the rear two sections. Next I glued the curved section on the back of the structure. At the front where the 16" gun barrels protrude I had to cut the three holes in to the plastic card and glue into position. Divide into three sections, with more plastic card so each gun barrel has its own compartment, at this stage the top remains open.
Next add detail on to the side of the gun housing. When this is done put all three sections to one side, because now we have to make the gun barrels. |
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| The first job was to warm up my
workshop where I keep my lathe, a Myford ML 7. I am still learning, but get bye, with a nice piece of metal in the chuck and rolling taper, I
turned the gun barrel. Now attach the blast bag to the barrel of the gun, because I am going to make a mould to cast all nine barrels the same. The blast bag is moulded from Milliput. This is a two part putty, which when mixed together will go hard at room temperature in 2-3 hours. Now to making the mould. Taking some scrap plastic card make a long four sided box, at least 1/2"longer each end of the barrel. With some play clay make a bed to sit the barrel into and then put the box around it. Mix some plaster of Paris and pour it into the mould. There are other materials you can use such as silicon moulding compound, this is especially good for soft metal moulding but is a lot more expensive. Leave the plaster over night to harden. Next take away the box and remove the play clay and release the barrel from the cast. |
 barrel mounted in play clay |
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Plaster two piece mould |
To make the other half, turn the mould over with the moulded section facing you. Replace the barrel, replace the box around it, wax every thing and mix more plaster. Pore the plaster into mould and leave to set. When completely set, take everything apart and we have a mould for our barrels. After taking the two moulds apart, cut two channels in the mould to allow a pour of melted metal and let the air out at the same time. | |||
| There are two options available for casting the barrel. First low melt metal or second casting resin. I chose low melt metal, because I wonder if resin will stand the test of time. First warm the mould up, but not to hot. Melt the soft metal and pour it in to the mould. Let it cool naturally; do not cool off in water. Remove the cast barrel from the mould and clean off the excess flash. One complete another eight to do. I did not make the barrels too long because the mould would be to long for casting. Instead I decided to add brass tube on to the end that fits into gun housing. To fix them into position I used plaster of Paris poured into the three compartments. Then fit a screw into the middle of the gun housing and filled this again with plaster. The top can now be glued in place with liquid poly. |
Gun barrels plastered in place. |
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