What is the technique?

Vacuum forming, is a simplified version of thermoforming, whereby a sheet of plastic is heated to a forming temperature, stretched onto or into a single-surface mould, and held against the mould by applying vacuum between the mould surface and the sheet.

 

What are the materials needed?

• Vacuum forming machine
• 3D object mould
• Plastic sheet

 

How to achieve the technique?

1. Power ON the machine and leave it to heat up for approx. 20mins.
2. Prep your 3D object moulds.

(I used a textured plastic cup, and a CNC-ed negative-positive mould.)

3. Cut the plastic sheet to desired size (small, medium, large) depending on the size of the mould.

4. Change the template according to the size of the plastic sheet (small to small, medium to medium, large to large)

5. Place the 3D object mould to the center of the machine.

6. Place the cut-out plastic sheet and lock the lever.

7. Pull out the heater over the plastic sheet until the plastic is stretched (no wrinkles = you’re good to go!)

8. Power ON the pump (and hold down the ‘Pressure’ knob if you want) while raising the mould in the machine by rotating the axle.

9.  Balloon can be seen if you want to form using pressure.

10. Form is formed!

 

What are the uses and applications of the technique?

• Packaging

 

Photos of experimentation with technique

Results of vacuum forming

Testing #1 was done with the textured plastic cup as the mould. I chose this cup because of its textures which I would like the plastic to “capture”.

Results below were achieved without the use of pressure.

 

Testing #2 was done with the CNC mould (positive side)

2^nd mould with an unsuccessful outcome while I was trying to get a “balloon” while holding down the knob for pressure.

 

Testing #3 was done with the CNC mould (negative side)

A successful piece after another attempt of using pressure to form the shape.

 

Final look of vacuum forming

 

Own personal reflections

The 3D objects that are used as the moulds are best not to be fully round or circular with no flat base as it will be difficult to release the mould from the formed plastic. The process itself in this technique allows the user for a couple trial and error. While working on this technique, I had to try a few times to achieve the balloon while pumping with pressure — the timing and contact between the plastic and the mould also plays a part.