Forming Methods

FORMING METHODS

PREPARATION OF SHEETS FOR FORMING

Hot Chemcast® GP can be handled much like a sheet of pure gum rubber and approximately the same force is required to stretch it. For making simple shapes, especially where thick Chemcast® GP is used, the weight of the material is often sufficient and only if considerable stretching is required should much pressure be applied. Most 3dimensional shapes may require the use of vacuum, air pressure, or mechanically or hydraulicallyactuated forms or combinations of these. Forms should be kept clean and brushed off before each piece is formed. They should also be stored carefully when not in use to protect them from denting, chipping, or warping. Such defects will show up in the Chemcast® GP on forming.

Before heating, the Chemcast® GP, cut somewhat oversize. is stripped of masking paper. Any specks of adhesive which adhere to the Chemcast® GP can be removed by dabbing with the gummed side of the masking paper. If the sheets are dusty or dirty, they should be washed and rinsed well. The sheet should be dried thoroughly by blotting with soft tissue paper. Otherwise, solids dissolved in ordinary tap water will bake into the Plastic surface when the material is heated. Operators should wear soft cotton gloves to avoid fingerprinting or scratching the sheets and should grip it only in the clamping area.

Methods:

Two Dimension Forming

Strip Heat Bending and Drape Forming

Three Dimension Forming

Three dimension shapes in Chemcast® GP are formed by stretching the heated material to the required contour. The force required to stretch the sheet can be supplied by manual labor, mechanical pressure, hydraulic pressure, vacuum, air pressure, or combinations of these depending on the forming method being used.

Free Forming

Vacuum Snapback Forming

Vacuum Drawing or Blowing into a Form

Vacuum Forming Equipment

Manual Stretch, Plug and Ring & Vacuum Assist Plug and Ring Forming

Blow-Back, Reverse Blow, Ridge, Male and Female Forming

Surface Embossing

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