Washer Head Bolts

Washer head bolts are used when the head of the bolt sits flush to a wooden member. The forged washer side provides a larger bearing surface so that when the bolt is tightened, the wood underneath the head is not damaged. Washer head bolts have an added semi-cone point and a thread length unique to pole line fasteners depending on the bolts length. Washer head bolts normally have a square nut assembled, but can also have a hex nut assembled.

Washerhead Bolt Drawing

Click table to show drawing
Bolt Diameter D H W B C F
Body Diameter Height (Head) Height (Washer) Outside Diameter (Washer) Width Across Corners (Head) Width Across Flats (Head)
Max Min Basic Max Min
12 0.515 0.290 0.130 1.40 1.061 0.995 34 0.750 0.725
58 0.642 0.420 0.125 1.80 1.326 1.244 1516 0.938 0.906
34 0.768 0.490 0.110 2.20 1.591 1.494 118 1.125 1.088
78 0.895 0.640 0.180 2.60 1.856 1.742 1516 1.312 1.269

Standard Thread Lengths

*Bolts shorter and/or smaller than those listed in the table shall have minimum thread lengths in accordance with American National Standard for Square and  Hex Bolts and Screws, B18.2.1*
Diameters Bolt length Thread length
  • 3/8"
  • 1/2"
  • 5/8"
  • 3/4"
  • 7/8"
  • 1"
4" up to less than 8" 3"
  • 3/8"
  • 1/2"
  • 5/8"
  • 3/4"
  • 7/8"
  • 1"
  • 1-1/4"
8" up to less than 12" 4"
  • 3/8"
  • 1/2"
  • 5/8"
  • 3/4"
  • 7/8"
  • 1"
  • 1-1/4"
12" and over 6"