Description
Truss Combo Chicago Screw Sizes, Post Lengths & Specifications
The chart below lists standard thread sizes, part numbers, barrel post lengths, thread depths, body diameters and head dimensions. Stock binding posts are available in lengths up to 2 inches, with custom extended lengths available for OEM production.
What Is a Truss Combo Chicago Screw?
A truss combo Chicago screw is a two-piece fastener consisting of an internally threaded female binding post and a matching male screw.
The barrel post passes through the materials being joined, and the mating screw threads into the post from the opposite side. When tightened, the two truss heads clamp the assembly together while maintaining a clean, low-profile appearance on both sides.
The combination drive accepts either a slotted or Phillips screwdriver, providing installation flexibility during production assembly, maintenance and field service.
Truss combo Chicago screws are also commonly searched as:
- Combination-drive binding posts
- Barrel nuts and screws
- Screw posts
- Male and female screws
- Binding screws
- Sex bolts
Unlike permanent rivets, Chicago screws can be removed and reinstalled when components require maintenance, replacement or adjustment.
Available Thread Sizes & Stock Post Lengths
Truss combo Chicago screws are available from stock in four standard inch thread sizes. Multiple barrel lengths make it easier to select the correct fastener for different panel and assembly thicknesses.
#8-32 Truss Combo Chicago Screws
- #8-32 × 1/4 in. Truss Combo Binding Post
- #8-32 × 3/8 in. Truss Combo Binding Post
- #8-32 × 1/2 in. Truss Combo Binding Post
- #8-32 × 5/8 in. Truss Combo Binding Post
- #8-32 × 3/4 in. Truss Combo Binding Post
- #8-32 × 1 in. Truss Combo Binding Post
- #8-32 × 1-3/8 in. Long Binding Post
#10-24 Truss Combo Chicago Screws
- #10-24 × 1/4 in. Truss Combo Binding Post
- #10-24 × 3/8 in. Truss Combo Binding Post
- #10-24 × 1/2 in. Truss Combo Binding Post
- #10-24 × 5/8 in. Truss Combo Binding Post
- #10-24 × 3/4 in. Truss Combo Binding Post
- #10-24 × 1 in. Truss Combo Binding Post
- #10-24 × 1-1/4 in. Long Binding Post
- #10-24 × 1-1/2 in. Long Binding Post
- #10-24 × 2 in. Extra-Long Binding Post
1/4-20 Truss Combo Chicago Screws
- 1/4-20 × 3/8 in. Truss Combo Binding Post
- 1/4-20 × 1/2 in. Truss Combo Binding Post
- 1/4-20 × 3/4 in. Truss Combo Binding Post
- 1/4-20 × 1 in. Truss Combo Binding Post
- 1/4-20 × 1-1/4 in. Long Binding Post
- 1/4-20 × 1-1/2 in. Long Binding Post
- 1/4-20 × 1-3/4 in. Long Binding Post
- 1/4-20 × 2 in. Extra-Long Binding Post
5/16-18 Truss Combo Chicago Screws
- 5/16-18 × 3/8 in. Truss Combo Binding Post
- 5/16-18 × 1/2 in. Truss Combo Binding Post
Refer to the specification chart above for exact part numbers, thread depths, body diameters, head diameters and head heights.
Long & Custom-Length Binding Posts
One of our key capabilities is supplying long and extra-long binding posts for applications where standard Chicago screws do not provide sufficient reach.
Stock options include:
- #8-32 binding posts up to 1-3/8 in.
- #10-24 binding posts up to 2 in.
- 1/4-20 binding posts up to 2 in.
Custom extended binding posts, barrel nuts and matching screws can be manufactured for OEM and production applications.
Custom options may include:
- Extended barrel post lengths
- Custom internal thread depths
- Special body diameters
- Custom head diameters and heights
- Matching screw lengths
- Alternative drive styles
- Custom materials and finishes
- Special packaging and labeling
For custom production, provide the thread size, required post length, total assembly thickness, body diameter, head dimensions, material, finish and estimated annual quantity.
How to Select the Correct Binding Post Length
The correct barrel post length depends primarily on the total thickness of the materials being joined.
Before selecting a Chicago screw or binding post, confirm:
- Total assembled material thickness
- Required barrel post length
- Mounting hole diameter
- Internal thread depth
- Mating screw length
- Required thread engagement
- Head diameter and available clearance
- Material and finish
- Required clamp load
The barrel post should pass through the assembly without excessive clearance. The mating screw must provide sufficient thread engagement without bottoming out inside the female post before the materials are fully clamped.
If the required length is not listed, provide the total assembly thickness or product drawing for a custom recommendation.
Materials & Finishes
Truss combo Chicago screws and binding posts are available in:
- Aluminum
- Aluminum and brass combinations
- Carbon steel
- Brass
- Stainless steel
Available finish options may include:
- Clear zinc
- Black zinc
- Chrome
- Nickel plating
- Brass plating
- Black oxide
- Decorative finishes
- Application-specific coatings
Steel provides economical strength for general industrial applications. Stainless steel offers greater corrosion resistance, while aluminum reduces assembly weight. Brass may be selected for its appearance, corrosion resistance or electrical properties.
Material and finish availability varies by thread size, post length and production quantity.
Benefits of the Combination Drive
The truss combination-drive head accepts either a slotted or Phillips screwdriver.
Key benefits include:
- Flexible installation with commonly available tools
- Easier production assembly and field service
- Reduced dependence on one screwdriver type
- Convenient removal and reinstallation
- Wide truss head for load distribution
- Clean, low-profile appearance
- Reusable fastening connection
The combination drive is not considered a security or tamper-resistant drive. Applications requiring restricted removal should use a dedicated one-way or security drive.
Truss Combo Chicago Screw Installation
Chicago screws and binding posts require access to both sides of the assembly.
Installation procedure:
- Prepare the correctly sized through-hole.
- Insert the female binding post from one side.
- Insert the matching screw from the opposite side.
- Engage the screw with the internal thread of the barrel post.
- Tighten using a slotted or Phillips screwdriver.
- Confirm adequate thread engagement without bottoming out.
A compatible thread-locking compound may be considered for applications exposed to vibration. Verify compatibility with the selected material and finish before production use.
Typical Applications
Standard and long truss combo Chicago screws are commonly used in:
- Furniture manufacturing
- Architectural panels
- Commercial partitions
- Electrical cabinets and enclosures
- Equipment panels
- Display fixtures
- Signage systems
- Fitness equipment
- Railings and guards
- Industrial machinery
- Thick panel assemblies
- Multi-layer material assemblies
- Leather goods
- Binders and sample books
- OEM product assemblies
Long binding posts are especially useful when joining thick panels, multiple material layers, spacers or components that exceed the reach of standard Chicago screws.
Factory-Direct Chicago Screws & Custom Binding Posts
Imperial Rivets & Fasteners supplies factory-direct truss combo Chicago screws, long binding posts, barrel nuts and matching screws to OEMs, manufacturers, distributors and industrial assembly operations.
We stock a broad selection of thread sizes and post lengths, including long binding posts up to 2 inches. Custom extended lengths, materials, finishes, head styles and mating screws are available for production requirements.
Select a standard part from the specification chart above and add it to your RFQ. If the required post length is not listed, send us your drawing or dimensional requirements for a custom production quote.
Questions or Custom Requirements?
Contact our sales team at sales@imperialrivet.com or (630) 964-0208.
