What Can We Help With: 608-587-2335


4GK Plastics offers numerous value-added services to enhance and further prepare your plastic injection molded parts. These services include:

  • Laser Engraving
  • Sonic and Hot Plate Welding
  • Heat Staking
  • Assembly

Additional information and descriptions about our services are listed below.

Contact Us to Learn More

Call 608-587-2335 or Sales@4gkplastics.com to start the conversation about partnering with us.

Laser Engraving

4GK Plastics laser engraving machine is capable of highly detailed, permanent engraving on metal or plastic. Laser markings will not chip, peel, smear or wash away and are not affected by humidity or other environmental conditions.

Sonic Welding

Sonic welding is a process in which a non-stationary part is vibrated against a stationary part at a high frequency. The friction created at the contact points effectively melts the parts at those points and welds them together. Through the process, the two parts are welded into a single part which cannot be disassembled.

Sonic welding normally is used when both parts are comprised of similar materials, however, metal inserts can be sonic welded into a part by vibrating the insert and forcing the surrounding plastic to melt and secure it.

Hot Plate Welding

Hot plate welding is used to weld two parts that are larger than would be practical for sonic welding. The parts are seated in custom fitted nests and a hot plate centered between them heats the contact points. The plate is then removed and the two parts are pressed together to form one complete part.

Heat Staking

Heat staking is a process of mechanically bonding two parts together which are comprised of dissimilar materials. This process can bond plastics with greatly differing melt points, or two completely different materials, such as metal and plastic.


Assembly can range from manually snapping two parts together to customized complex insertion procedures. For one customer, 4GK Plastics designed and manufactured pneumatic assembly devices and fixtures to insert a small integrated circuit board into a molded part.