CASE STUDY: HVAC | Commercial Air Conditioning

Engineering And Part Consolidation Offers Long–term Financial Impact

 A commercial air conditioning manufacturer partnered with Optimas to re-engineer an electrical control box and significantly reduce part and manufacturing costs.

Annualized Real Results, Real Impact


Inner Mounting
Plate Elimination




Screw Consolidation/


An existing customer invited Optimas to explore a cost saving initiative relating to an electrical control box in a commercial air conditioning unit. Prior innovation failed to develop a fastening solution which would yield cost savings.

The original design of the control box enclosure contains a large steel stamping along with an outer casing that is installed on the face of the cabinet. This acts as a sealed unit to prevent leaks and moisture. 

The internal plate is designed and manufactured with a large range of pre-pierced holes to house every potential electrical component configuration. On average, the customer only used 30% of the holes built into the electrical control box.


A cost–and labor–savings initiative that eliminated an under–used part of an electrical control box in a commercial air conditioning unit.


Design a “dimple” style fastening system, including a range of sharp-crested, thread–forming screws, that engages on contact with walls and:

  • Adheres to UL production requirements
  • Eases the mounting process during manufacturing
  • Allows for “change outs” in the field
  • Ensures a watertight seal


  • “Dimple” design eliminated the electrical control box inner panel and passed UL, weather and transit testing.
  • Re-designed screws lowered the torque required for installation compared to standard thread-forming fasteners.
  • Eliminated debris created or left in the joint during thethreading/installation.
  • Field repairs/additional components can be made with standard machine screws installed into existing threads.
Close-up of fastener missing threads

OEM Fastener: A standard trilobular screw can’t engage with a dimple pressed into the stamped metal wall of an electrical control box.

Side by side comparision of OEM fastener missing threads and Optimas fastener with engineered threads to end of fastener shank

New Fastener: Replaced a trilobular, thread–forming screw (left) with a trilobular, sharp–crested, thread–forming screw (right) to engage the dimple.

Control Box Fastener Dimples

Optimas Solution: Fastened components to the inside wall of an electrical control box and met all manufacturing and field-use requirements.