Square Nuts in Zinc Plated Steel
Four Sided Nuts
Square nuts can be used in a channel or welded to other steel products. A square nut is a four-sided finish nut. Compared to standard hex nuts, square nuts have greater surface contact with the part being fastened. Therefore, they have a greater resistance to loosening than standard hex nuts, but also greater resistance to tightening, making these nuts a little harder to install securely. They are also much less likely to become rounded-off after repeated loosening/tightening cycles.
Square nuts are typically mated with square-headed bolts. Square nuts are used along with flat washers to avoid damage from its sharp edges and increase the fastener's strength. They are installed on the opposite side of the materials being fastened. With the bolt head or machine screw head on the other side, they compress the materials together for a secure fit.
Square Nut Specifications - Zinc Plated Steel
| Nut Size | Width Across Flats | Thickness |
| 1/4" | Max 0.438-Min 0.423 | Max 0.235-Min 0.203 |
| 5/16" | Max 0.562-Min 0.545 | Max 0.283-Min 0.249 |
| 3/8" | Max 0.625-Min 0.607 | Max 0.346-Min 0.310 |
| 7/16" | Max 0.750-Min 0.728 | Max 0.394-Min 0.356 |
| 1/2" | Max 0.812-Min 0.788 | Max 0.458-Min 0.418 |
| 5/8" | Max 1.000-Min 0.969 | Max 0.569-Min 0.525 |
| 3/4" | Max 1.125-Min 1.088 | Max 0.680-Min 0.632 |
| 7/8" | Max 1.312-Min 1.269 | Max 0.792-Min 0.740 |
| 1" | Max 1.500-Min 1.450 | Max 0.903-Min 0.847 |
Zinc Plated Steel
Zinc is by far the most common and economical type of plating for fasteners. The zinc plating adds a protective "sacrificial" top layer against corrosion while also adding a shiny finish to the fastener. Zinc plating is ideal for indoor use, where it won't be constantly exposed to harsh elements.
FAQs
Why are nuts hexagonal in shape?
Must nuts have a hexagonal shape because it's easier to grip. With six sides, you can turn a nut just one-sixth of the way to reach the next flat parallel. In contrast, you have to turn one-quarter of the way for square nuts.
How do you tighten a square nut?
Square nuts can be tightened with pliers or a wrench, making them ideal for use in blind locations. The pliers or wrench only need a sturdy grip to secure these nuts.
Why are square nuts not used as much as hex nuts?
Square nuts were common mostly because they were easy to manufacture, especially by hand. Hex nuts are more common now, thanks to the six sides granting more angles that a tool can fasten from, making it generally easier to fasten down.
What is zinc plated steel?
Zinc plated steel is steel that goes through adding a layer or coating of zinc to protect the steel from corrosion. The added layer of zinc sacrifices itself to keep the steel from rusting, even if the plating is damaged.
