Formech Vacuum Former
Metal Workshop (Room G15)
Level 03 - Machine Certification
The vacuum former applies heat and pressure to a sheet of plastic in order to stretch it over a single-surface mold. The plastic is held in place and heated before it is forced against the mold by a vacuum (suction of air). The mould if designed effectively can be removed and reused for further vacuum forming. The vacuum forming process can be used to make a wide variety of products such as product packaging, speaker casings and car dashboards.
Video of Operation
- Refer to the Vacuum Former Summary Guide.
Health and Safety
- The vacuum former melts plastic during operation. Never touch the heating box, any of the heating elements or the molten plastic when using the vacuum former.
- The vacuum former melts plastic during printing. Plastic odours are emitted during this operation. Make sure the vacuum former is used in a well-ventilated area.
- Take care to ensure that the heating element is moved away from the plastics material before the vacuum forming process begins.
- Ensure that the air pressure vacuum is released to zero before releasing the clamping arrangements.
- Always turn the machine off when not in use. NEVER leave the machine unattended while in use.
- Parts of the machine reach high temperatures. All people should be kept a safe distance from work area. Do not let visitors contact tool while operating.
- Start up: Turn on the vacuum former. The screen on the front panel will illuminate.
- Place Mold: With the heater pushed fully back, place the table in the up position by pulling the table lever close to you. Place your mold onto the table. Place the table in the lower position by pushing the table lever away from you.
- Load Plastic: Position a sheet of plastic over the aperture. The plastic should completely cover the white seals around the aperture. Pull the clamps frame down and close the materials clamps. Depending on the plastic thickness, you may need to use the adjusting screws on the material clamps to properly grip the plastic.
- Heat plastic: Press RUN to start the cycle. With the heater pushed fully back, place the table in the up position by pulling the table lever close to you. The heater timer will begin counting down. It may be necessary to move the heater back a little to check the plastic is sufficiently heated.
- Form around Mold: When the plastic is soft enough push the heater fully back then pull the crank handle forwards to lift the table and mold tool into the soft plastic, after which the table lock and seals in position. When the table is sealed press the “Start Vacuum” button. The screen changes to show the Vacuum latched ON. The vacuum can be turned ON/OFF by pressing this button. Monitor the forming to ensure you have achieved the correct definition.
- Release: When the plastic has cooled press “Release” to push air under the plastic to lift the mold from the tool. Press “Finish” when the molding is complete and has released from the mold.
- Shut down and remove materials: Remove all molds, tools and formed plastic from the vacuum former and leave in a clean and tidy state. Push the heater back into the protective slot. Turn off the power to the machine via the power switch at the rear of the machine.
- You will need to have a detailed understanding of the machine to prepare your mold. Mold design is critical to the success of the vacuum former. There are two basic types of molds, a male and a female mold. Read the Vacuum former guidelines for more detailed information about mold design.
- There are a number of limitations to the vaccum former that are inherent in the process of stretching plastic. One limitation is the machine's ability to effectively form vertical corners. As such it is best to design molds with a taper (known as the draught angle) to ensure even thickness of plastic, avoid webbing and facilitate mold removal. This angle is typically 5-7 degrees for male molds and 2-3 for females.
- Once the plastic has reached its forming temperature or plastic state it can be pre-stretched by forcing air up into the plastic to form a bubble like shape. This pre stretching ensures that the resulting part will have an even wall thickness when the vacuum is applied.
- The molds used in the vacuum former can be a range of different materials such as wood, clay, plaster, epoxy resins, foams and aluminium.