Materials:

Polystyrene sheet (approx 1700mm in length x 600mm wide x 25mm thick)

UHU (All Purpose Adhesive) 32ml

EVO-STIK Grab N Fill (Gap filling adhesive) to be used with mastic gun

PlastiKote (Matt Super Spray Paint) 400ml
Colour = Black

Scissors

Tea Light (flickering tea light)

Platube LED Shoelaces (1 pair)
(We will only use about half of the lace cut up into 5 smaller pieces and glued together.)

Hot wire cutting machine

Soldering iron

Ruler

Marker pen

Protective face mask (use when spraying paint, soldering and cutting the foam using the hot wire machine).

Step 1: CUTTING THE FOAM SHEET

Measure, mark and cut the foam sheet using the following dimensions:

Cut 1 = 300mm (place one half of this sheet to the side for later to make the fuse rings from).
Cut 2 = 300mm
Cut 3 = 300mm
Cut 4 = 280mm
Cut 5 = 250mm
Cut 6 = 200mm

Then cut the 6 pieces in half see image.

Giving you 12 pieces in total

Step 2: HOT WIRE CUTTING (Measuring and Cutting the Circles)

Starting with one of the 300mm pieces find the centre point and then measure from the wire 149.50mm and make the angle of the wire vertical (90 degrees) and cut.

This should give you a circle diameter of 298.90mm after cutting and will be the centre circle of the bomb.

Do the same for the the remaining sheets using the following measurements.

(Cut from 300mm sheet) 149.50mm to the centre @ 90 degrees = Total diameter (298.90mm)
(Cut from 300mm sheet) 149.50mm to the centre @ 80.37 degrees = Total diameter (298.90mm)
(Cut from 300mm sheet) 145.20mm to the centre @ 70.44 degrees = Total diameter (290.04mm)
(Cut from 280mm sheet) 136.35mm to the centre @ 59.84 degrees = Total diameter (270.27mm)
(Cut from 250mm sheet) 121.80mm to the centre @ 47.86 degrees = Total diameter (240.36mm)
(Cut from 200mm sheet) 99.20mm to the centre @ 32.48 degrees = Total diameter (198.40mm)

Stack together as shown in the image and glue.

Step 3: FUSE

Cut 2 circles out of the remaining 300mm sheet at the following measurements.

50mm to the centre & 90 degrees = Total diameter (100mm)

Stack the 2 circles together and glue.

Take your Tea Light and position it onto the edge of the 2 circles just glued and draw around ready for cutting out. And using the soldering iron trace the circle just drawn.

Take hold of your Platube LED lace and measure about 100mm and cut x5 and glue together.

See image.