Description
Open End Binding Post Sizes, Dimensions & Specifications
The table below lists standard open end binding post sizes, including thread size, post length, body diameter, head diameter, and head height. Select a size to add it directly to your RFQ. Custom lengths, materials, and finishes are also available.
| PART NO. | Thread Size-F | Length-L | Body Dia-D | Head Dia-A | Head Height-H |
|---|---|---|---|---|---|
| ATB832-18 | 8-32 Thread | 1/8″ | 0.203″ | 0.42″ | 0.06″ |
| ATB832-316 | 8-32 Thread | 3/16″ | 0.203″ | 0.42″ | 0.06″ |
| ATB832-14 | 8-32 Thread | 1/4″ | 0.203″ | 0.42″ | 0.06″ |
| ATB832-38 | 8-32 Thread | 3/8″ | 0.203″ | 0.42″ | 0.06″ |
| ATB832-12 | 8-32 Thread | 1/2″ | 0.203″ | 0.42″ | 0.06″ |
Matching Binding Post Screw Sizes & Specifications
The table below lists standard matching male screw sizes, including thread size, screw length, head diameter, and head height. Other screw lengths and configurations are available upon request.
| Part No. | Thread Size / D | Length / L | Head Dia / A | Head Height / H |
|---|---|---|---|---|
| AM832-316 | 8-32 Thread | 3/16″ | 0.413″ | 0.080″ |
| AM832-14 | 8-32 Thread | 1/4″ | 0.413″ | 0.080″ |
| AM832-516 | 8-32 Thread | 5/16″ | 0.413″ | 0.080″ |
| AM832-38 | 8-32 Thread | 3/8″ | 0.413″ | 0.080″ |
What Are Open-End Binding Posts and Screws?
Open-end binding posts and screws are a two-piece fastening system consisting of an internally threaded female post and a matching male screw.
The post passes through the materials being assembled, and the screw threads into the post from the opposite side. The two heads create a clean, finished appearance on both sides of the assembly.
Unlike a closed-end post, an open-end post has a through-hole that allows a longer mating screw to extend farther into or through the female post. This provides greater flexibility when joining thicker, variable-thickness or multi-layer materials.
These fasteners are also commonly called:
- Open-end Chicago screws
- Binding posts and screws
- Screw posts
- Barrel nuts and screws
- Binder posts
- Sex bolts
- Male and female screw sets
- Through-hole binding posts
Using these alternate names naturally helps customers who describe the same fastening system differently.
Open-End vs. Closed-End Binding Posts
Open-end binding posts have an opening through the female post. This allows additional screw engagement and greater flexibility when using longer mating screws.
Closed-end binding posts have a fixed internal thread depth. They prevent the screw from passing through the end of the post and provide a closed exterior surface.
Choose an open-end post when:
- Greater thread engagement is required.
- Different screw lengths may be used.
- Material thickness varies between assemblies.
- The screw may need to extend through the post.
- A through-hole post is specified on the drawing.
Choose a closed-end post when the exterior end must remain closed or screw penetration must be limited.
Standard Open-End Binding Post Sizes
Standard #8-32 open-end binding posts are available in the following listed lengths:
- #8-32 × 1/8″ Open-End Binding Post
- #8-32 × 3/16″ Open-End Binding Post
- #8-32 × 1/4″ Open-End Binding Post
- #8-32 × 5/16″ Open-End Binding Post
- #8-32 × 3/8″ Open-End Binding Post
- #8-32 × 1/2″ Open-End Binding Post
Standard #8-32 post dimensions:
- Body Diameter: 0.203″
- Head Diameter: 0.420″
- Head Height: 0.060″
Additional thread sizes and longer post lengths may be available depending on material, head style and production quantity.
Refer to the specification table above for current part numbers and exact dimensions.
Matching Slotted Screws
Male slotted screws are available to match the female binding post thread.
Available screw thread sizes include:
- #6-32 Slotted Screw
- #8-32 Slotted Screw
- #10-24 Slotted Screw
- 1/4-20 Slotted Screw
- 5/16-18 Slotted Screw
Common #8-32 screw lengths include:
- #8-32 × 3/16″ Slotted Screw
- #8-32 × 1/4″ Slotted Screw
- #8-32 × 5/16″ Slotted Screw
- #8-32 × 3/8″ Slotted Screw
Screw length must be selected according to the post length, total material thickness and required thread engagement.
Matching posts and screws may be supplied as complete sets or as separate components, depending on the project requirements.
Materials & Finishes
Open-end binding posts and screws are available in several materials and finishes.
- Aluminum: Lightweight and corrosion resistant
- Brass-Plated Aluminum: Lightweight with a decorative brass appearance
- Zinc-Plated Steel: Strong and economical for general industrial use
- Chrome-Plated Steel: Provides a bright decorative finish
- Brass: Offers corrosion resistance, conductivity and decorative appearance
- Stainless Steel: Provides strength and increased corrosion resistance
Clear zinc, black zinc, brass, chrome and other application-specific finishes may be available.
Material and finish availability varies by thread size, post length, head style and production quantity.
How to Select the Correct Post and Screw
When selecting an open-end binding post assembly, consider:
- Total thickness of the materials being joined
- Female post thread size
- Female post length
- Male screw length
- Required thread engagement
- Post body diameter
- Head diameter and profile
- Screw drive style
- Material
- Finish or color
- Required quantity
The post length should generally correspond to the thickness of the assembled materials. The mating screw must provide sufficient thread engagement without creating unwanted projection.
For an existing application, provide the post thread, body diameter, post length, head diameter and matching screw dimensions.
Assembly
Open-end binding posts and screws are installed from opposite sides of the materials being joined.
General assembly procedure:
- Prepare an assembly hole that fits the post body.
- Insert the female post through the materials.
- Insert the matching male screw from the opposite side.
- Thread the screw into the post.
- Tighten until the components are securely clamped.
The assembly can be removed and reinstalled when access or replacement is required.
For applications exposed to vibration, ask about thread-locking patches, adhesives or other retention options.
Typical Applications
Open-end binding posts and screws are commonly used in:
- Leather belts, bags and straps
- Bookbinding and document assembly
- Product catalogs and sample books
- Menus and presentation folders
- Packaging and reusable sample kits
- Furniture and cabinet assembly
- Architectural panels
- Retail displays and signage
- Electrical and equipment panels
- Multi-layer material assemblies
- Industrial hardware
- OEM-manufactured products
Their removable two-piece construction makes them useful when an assembly may need to be opened, adjusted or serviced.
Factory-Direct Supply & Custom Options
Imperial Rivets & Fasteners supplies factory-direct open-end binding posts, Chicago screws and matching male screws for distributors, manufacturers and OEM production.
Available custom options may include:
- Custom female post lengths
- Custom male screw lengths
- Special thread sizes
- Flat, round and truss heads
- Slotted, Phillips, combination and six-lobe drives
- Aluminum, steel, brass and stainless steel
- Clear zinc, black zinc, brass and chrome finishes
- Parts manufactured to drawings or samples
- Matching post-and-screw sets
- Production-volume packaging
Select a standard post and screw combination from the specification table and add it to your RFQ. If the required length, thread, head or finish is not listed, send our sales team your drawing or sample for review.
Questions or Custom Requirements?
Contact our sales team at sales@imperialrivet.com or (630) 964-0208.
