Thermoforming is a process wherein a material such as plastic is molded into shapes using heat. In solid surfaces and thermoformable materials. It is a popular way to make use of the solid surface to create curves and rounded shapes. This is where surfacing materials such as granite and quartz cannot be used.
The ability to thermoform is what makes solid surfaces a favorite for designers who regularly use three-dimensional fixtures and installations in their job.
In order to start the process of shaping the solid surface material. Careful preparations must be made. It is first achieved by heating the material to the point that it becomes flexible.
Additionally, attention needs to be given to the following factors when you start shaping the material.
The material needs to be cut slightly larger than the final dimension. This is because as the material is heated it begins to shrink. The edges of the material also need to be sanded smooth and made sure that no chip, cracks, or scratches are visible or present. This is due to the fact that even small chips, cracks, and scratches becomes a starting point for the material to develop them at a later time.
It is also advised that the entire material must be heated equally. This is because if heated in small sections the material tend to develop stress points which will affect the durability of the material in the future. It also must be heated accordingly based on the composition of the material.
Acrylic based materials are the most flexible when heated to the proper temperature. Next is a blend of acrylic and polyester which is second flexible. Last being a full polyester material being the least flexible.
Make sure not to heat the material too much or too little. Underheating can cause it to develop cracks, stretch marks, and cause breaking. Overheating also causes the material to bubble or blister and may result in the color to change. Heating in general may also cause it to darken in color depending on the dye used in manufacturing.
When the Material has reached the appropriate temperature, it is best to remove it from the oven and slowly bending it over to shape into the desired form. Careful in bending it too fast as it may cause it to crack, break, or develop stretch marks. If it is also bent too slowly it may start to cool to soon.
Molds can be made by creating a set of male and female molds using plywood or MDF. The material needs to be placed in between while it cools. The material needs to cool down below 170°F before it must be removed.
Using forms and molds must be checked carefully as any imperfections contained in their surface will be transferred to the material after thermoforming. This might affect the final quality and desired design of the material. One method to eliminate such markings is to line the surface of the mold using tempered hardboard which is also known as a peg board just without the holes.
If a vacuum press is available. It can be used to help the material conform to the desired shape. It is however beneficial to use a specially shaped piece of wood to coax the material into position. Sprinkling a light layer of talcum powder is also great for making the entire process easier.
The material needs to be fixed in place until it has reached a surface temperature of 180°F. Then slowly remove the restraints so the material is able to release stress. Also, take note that 180°F is the specified temperature suggested for Corian, other materials might have different specifications so always refer to the manufacturer.
After thermoforming is complete the process of seaming and other modifications can be applied to the material. It is important that during this time that you must consult your manufacturer about the specifications of the material. This is to avoid the material from being damaged or installed incorrectly.
Oven comes in three styles used in thermoforming. They are the infrared/radiant ovens, hot air/convection ovens, and the platen press. It doesn’t really matter what kind of oven you use just as long as it is big enough to contain the entire piece of the material. Also, make sure to calibrate the oven based on the specifications provided by the manufacturer.
*Platen Press – is specially designed to come into contact with the material. It is known to heat up the material faster than the other two.
*Infrared/Radiant Oven – is an oven made to transfer energy using electromagnetic radiation as a source of heat. This is then transferred to the material which gets heated as well.
*Air/Convection Oven – A convection oven uses hot air circulated by a fan to evenly heat the surface or the oven. This reduces the chances of uneven heating.