Description of vacuum forming simply stated vacuum forming is the process of taking a flat sheet of plastic and changing it into a contoured shape.
Vacuum forming plastic thickness.
Because the plastic is fairly low density it is easy to work with small hand tools.
The stretching of a flat sheet of plastic material into a larger shape results in a larger surface area and a corresponding reduction in the sheet s original thickness.
The thicker the plastic the stronger but the less detail.
This is accomplished by putting a piece of plastic into some type of clamping mechanism heating the sheet up to a forming temperature.
This plastic is very friendly to and its use is well known by the modeling community.
Vacuum forming material selection guide.
This vacuum forming material selection guide is part of our free help with vacuum forming it lists most common vacuum forming materials their basic properties in standard grade some advice on costs typical uses for formings made from each material type.
Each plastic material has a variety of different properties and they form at different temperatures.
The acrylic petg and polycarbonate sheets are normally clear can be special ordered in colors however the polycarbonate may have to be heat dried prior to the vacuum forming temperature phase depending on thickness.
Thermoforming is the forming of heated plastic on a mold to create a desired shape.
These features are typically needed to allow for part strength retention of material thickness and or esthetics.
So if 15 mil material is required for a specific project or application the fill thickness will be specified as 15 mils nominal after forming many manufacturers simply utilize heat and vacuum to form the sheets as this is the least costly technique and the most rudimentary to operate and maintain.
The key to good part design in thermoforming is understanding the need for a proper size radius or chamfer.
Vacuum forming plastic choices styrene high impact poly styrene hips generally the best version of thermoforming plastic for modelers.
All thermoforming techniques are stretching processes.
Vacuum forming thin plastics works best they will adhere and take in better detail but 90 abs plastic is what everyone uses for stormtrooper armor and other props when they vacuum form i think westerfields armor uses 65 thick not sure though.
Thermoforming vacuum forming and pressure forming are considered thermoforming processes.
The thinning down of the sheet s original thickness is not necessarily uniform.
Because all vacuum forming starts from a flat sheet the wall thickness of the formed part will have a variable wall thickness as the material is.
One of the most difficult features in thermoforming is the three sided sharp corner in a female mold.