- A vacuum cleaner
- A hair drier
- 6mm MDF
- Araldite / Superglue (I used 5 minute Araldite)
- Duct tape
- PETG plastic sheet, 0.5mm thick or less
- Mole grips or pliers
0:28 Cut 3x 5cm squares out of 6mm MDF, and mark their centres by drawing lines diagonally from corner to corner on each.
0:42 Centre the vacuum cleaner nozzle on one of the MDF squares and draw around it.
1:07 Use a forstner or paddle bit that's slightly smaller than the outside diameter of the vacuum nozzle, to drill a hole in that square.
1:23 File and sand the hole so it's a tight fit on the vacuum nozzle.
1:34 Drill a hole a few millimeters smaller than the outer diameter of the vacuum nozzle in the centre of another MDF square.
2:02 Cut out the shape you want to form into the plastic. I cut a roughly 2cm diameter circle out of 3mm thick MDF.
(step not shown in video) Cut 4x triangular shapes out of the 6mm thick MDF. The triangles should measure roughly 1cm along each side.
3:14 Superglue the 3mm circle to the centre of the MDF square which doesn't have a hole drilled in it. That will form the mould itself.
3:20 Superglue the two squares with the holes in together in a stack.
3:30 Superglue the triangular MDF pieces to the corners of the MDF square with the smaller hole in it.
3:52 Using a drill bit which is between 1mm and 0.5mm diameter, drill lots of holes all the way through the mould. The holes should be spaced roughly 4-5mm apart.
4:31 Superglue the mould to the top of the 4 triangles. So all the bits of wood you cut out are now glued together in a stack.
4:39 Once all the superglue has dried, duct tape around the sides, which seals the holes in the sides underneath the mould.
5:28 Cut 2 more squares out of the 6mm MDF, roughly 9-10cm square. Cut square holes in the centre of each of them; in one piece, the hole should be about 6cm square, and in the other, the hole should be about 8cm square.
5:47 Cut a 7cm square out of the PETG plastic.
6:00 Remove the protective covering from the PETG and trap it between the 10cm square bits of MDF. I found mole grips are best to hold those squares together, not the bulldog clips shown in the video. Mole grips allow you to hold the assembly without burning your fingers.
6:25 Fit the mould assembly on the vacuum nozzle. I clamped the vacuum nozzle to my work surface, facing sideways. Turn the vacuum cleaner on, and turn the hair drier to its hottest setting and hold it close to the PETG sheet.
6:49 After 20-30 seconds the PETG should start to bulge a little. Quickly place it over the mould.
7:12 Turn off the vacuum cleaner and remove the PETG from the mould. It probably isn't necessary to heat the PETG whilst it's on the mould, and this can do more harm than good because the PETG can start to bubble if it gets too hot.
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