Heavy Copper Printed Circuit Boards

Epec has been building heavy copper circuit boards with traces and copper planes of up to 6 ounces for over 20 years. Our expertise is in producing at a reasonable cost, heavy copper PCB's that are of proven designs. Our engineering team can work with you to review your design to make sure that they can be manufactured with the highest quality at the best overall cost.


Industries Served Using Heavy Copper Circuit Boards

  • Welding Equipment
  • Solar Panel Manufacturers
  • Power Supplies
  • Automotive
  • Electrical Power Distribution
  • Power Converters

Heavy Copper Printed Circuit Board


Heavy Copper PCB Capabilities

  • Maximum Number of Layers = 16
  • Laminate – FR-4 (All Tg Ranges), Teflon, Ceramic
  • Finished Thickness = .020" - .275"
  • Green, Blue, Red, Black, Clear & White Solder Masks & Legend Inks
  • Minimum Soldermask Clearance – 6 mils
  • Minimum Solder Dam Width – 5.5 mils
  • Hot Air Solder Leveling (HASL)
  • Immersion Gold (ENIG) & Immersion Silver
  • Blind & Buried Vias
  • Minimum Drill Bit Hole Size = .012"
  • Minimum Holes Size - .008" +.005"/-.008"
  • Maximum Hole Aspect Ratio = 10:1
  • Maximum Copper Weight = 6 oz. (UL Approved)
  • Controlled Impedance +/- 10%
  • Minimum Silkscreen Line Width – 8 mils

Production Minimums

Measured in Inches Hoz 1oz 2oz 3oz 4oz 5oz 6oz
Min. Conductor Width 0.004 0.005 0.006 0.007 0.008 0.009 0.010
Min. Conductor Spacing 0.004 0.006 0.008 0.012 0.014 0.017 0.020
Min. Pad to Pad Spacing 0.004 0.006 0.008 0.012 0.014 0.017 0.020
Min. Conductor-to-Pad Spacing 0.004 0.006 0.008 0.012 0.014 0.017 0.020
Min. PTH Annular Ring 0.006 0.006 0.008 0.009 0.011 0.013 0.014
Min. VIA Annular Ring 0.006 0.006 0.008 0.009 0.011 0.013 0.014
Min. Distance - Hole to Board Edge 0.010 0.010 0.010 0.010 0.010 0.010 0.010

See our EXTREME Copper PCB's for information on copper weights over 6 oz.

America's Oldest, A History of Innovation.  Learn More →
Our History

As the oldest production Printed Circuit Board Company in North America, perhaps in the world, the 60-year plus story of Epec is connected to the development of the PCB and the electronics industry.

See our history timeline →



  • Epec Founded in 1952
  • IPC Founded in 1957
  • Epec Builds PCB for Apollo 11