Shopping Cart

Your cart is empty.

Your cart is empty.

Carriage Bolt Zinc Plated 307A Grade A Steel - 1/4'-20 x 8 PT - Qty-25

Free shipping on orders over $29.99

$22.48

$ 10 .99 $10.99

In Stock

About this item

  • A carriage bolt has a domed or countersunk head and the shank is topped by a short square section under the head of the bolt.
  • The square section grips into the part being fixed, preventing the bolt from turning when the nut is tightened.
  • Carriage bolts are often used to fasten wood panels or board to masonry or to one another.
  • The square shank of the bolt allows it to lock into place when inserted into a round hole in wood or a square hole in a metal strap, the unthreaded square shank pulls into the wood creating a tight connection.
  • Bolts Over 6" in length will have a shoulder beneath the head.



Product Description

Carriage Bolts - Zinc Plated Steel

  • Fully threaded down to the square section beneath the head which grips into the part being fixed (typically wood)
  • Commonly used to fasten wood panels to masonry or one another
  • Also features a domed head
  • 307A Zinc plating offers an extra layer of corrosion resistance and a shiny finish to class 4.6 steel
  • Commonly used with hex nuts, flat washers, and wood applications

DESCRIPTION

Carriage bolts have a domed head, and the shank is topped by a short square section under the head of the bolt. The square section grips into the part being fixed, preventing the bolt from turning when the nut is tightened. Carriage bolts are often used to fasten wood panels or board to masonry or one another, as well as wood beams. The square shank of the bolt allows it to lock into place when inserted into a round hole in wood or a square hole in a metal strap, and the unthreaded square shank pulls into the wood, creating a tight connection. Shorter length carriage bolts are fully threaded(FT), while longer lengths may be partially threaded(PT). These will be designated in the listing having either FT or PT in the title.

Product Specifications

  • Material: 307A Zinc Plated Steel
  • Head Style: Dome
  • Filet Radius: 0.031
  • Head Diameter: Max 0.594 - Min 0.563
  • Head Height: Max 0.145 - Min 0.125
  • Square Neck Depth: Max 0.156 - Min 0.125
  • Square Neck Width: Max 0.260 - Min 0.245
  • Thread Diameter: 1/4"
  • Thread Size: 1/4"-20
  • Thread Pitch: 20 per Inch
  • Thread Direction: Right Hand
  • Thread Type: UNC Coarse
  • Standards met: REACH and RoHS Compliant
  • Sizing: Diameter - Thread Pitch x Overall Length

Carriage Bolts - Zinc Plated Steel

zinc plated steel carriage bolt

307A Zinc Plated Steel

307A Zinc plating offers an extra layer of corrosion resistance and a shiny finish to class 4.6 steel

zinc plated steel carriage bolt

Domed Head

Carriage bolts feature a domed, driver-less head with a short square section under the head of the bolt, preventing the bolt from turning when the nut is tightened.

zinc plated steel carriage bolt

Common Applications

Carriage bolts are commonly used for fastening wood beams and panels to masonry or to one another. The square shank of the bolt allows it to lock into place when inserted into a round hole in wood or a square hole in metal, the unthreaded square shank pulls into the wood creating a tight connection that locks the bolt into place.

Listing photo is generic for the fastener type listed in this listing and is not to scale. Please refer to the description for fastener details. If in doubt, please ask a question through chat or email. We will respond with the requested information quickly.


Mark
Reviewed in the United States on July 13, 2023
You know how the old saying goes...."once you've seen a carriage bolt, you've seen them all"....That addage does not apply here. This 1/4 carriage bolt could easily win a beauty contest, putting other fasteners and related shoulder stop bolts to shame. Because of it's impressive length, this bolt stands head and shoulders above the crowd. What makes this bolt so great? Well, I can't identify once specific reason... maybe it's because all of it's glowing attributes make it so hard to isolate just one. Maybe it's the chinese mass production that sets it apart from others...or maybe it the shiny zinc plating. Or maybe it's the 1/4 x 20 threads. Did I mention this bolt has a shoulder? What a shame that this bolt has to be used to hold things together, and thus be hidden from the world to see. Too bad this bolt couldn't be shown off before it's long and grueling life as a fastner....being forcefully mated to a random nut, tightened down to bind some 2x4 studs together, or some random project for the DIY guy...or holding together a rugged picnic table. We know, however, that this bolt will forever be in our hearts, as the pristine example of modern engineering that we have all come to know and love.
Recommended Products