Metal Text Screws for Metal Joints | Hebei Wotu Fastener Manufacturing Co., Ltd.
A metal text screw inquiry needs one clarification before size or finish can be selected: what materials will the screw join, and is the receiving metal pre-drilled? For metal-to-metal work, the practical choice is usually between a self-drilling screw that forms its own entry hole and a self-tapping screw used with a suitable pilot hole.
Head style, thread form, length and coating then determine whether the fastener fits the joint, seats correctly and resists the surrounding conditions. A screw for thin sheet, a roof panel or a metal-to-wood assembly should not be specified in the same way.
Brand: Hengzuan Surface: blue and white zinc plated Specifications: in stock ST2.9/ST3.5/ST4.2/ST4.8/ST5.5 Chinese national standard full series, complete rod length 13~60mm, supports nonstandard length customization; drilling adapts to steel sheet thickness 2~6mm Packaging: 25kg cartons, whole wooden pallets
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Brand: Hengzuan Surface: Color zinc plated, optional blue-white zinc plated, black oxide treatment Specifications: Chinese national standard ST4.2/ST4.8/ST5.5 specifications, rod length 13~50mm in stock, supports nonstandard length customization Packaging: 25kg export cartons, full wooden pallets wrapped with film, supports neutral packaging, private-label customization
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Brand: Hengzuan Surface: blue and white zinc plated, can be customized color zinc plated, black oxide plated Specifications: Comply with GB/T15856.2-2002 Chinese national standard, in stock ST4.2/ST4.8/ST5.5 full range of specifications, length 13mm~75mm optional, supports customized nonstandard rod lengths; drilling adaptation plate thickness 0.7~6mm Packaging: 25kg export cartons, full pallets wrapped with film, supports neutral export packaging, customer private-label customization
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Brand: Hengzuan Surface: blue and white zinc plated, can be customized color zinc plated, black oxide plated Specifications: in stock 3.5/3.9/4.2/4.8/5.5 mainstream wire diameter, rod length 13mm~75mm full size range, nonstandard length can be customized as needed Packaging: 25kg export cartons, full wooden pallets wrapped with film, supports neutral export packaging, private-label customization
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Brand: Hengzuan Surface: color zinc plated, customized blue-white zinc plated, black oxide Specifications: in stock 3.9/4.2/4.8/5.5 full diameter, length 13mm~75mm full size range, supports customized nonstandard rod lengths Packaging: 25kg export cartons, full pallets wrapped with film, supports neutral export packaging, customer private-label customization
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Brand: Hengzuan Surface: blue and white zinc plated, can be customized color zinc plated, black oxide plated Specifications: Comply with GB/T15856.2 Chinese national standard, in stock ST3.5/ST4.2/ST4.8/ST5.5 mainstream wire diameter, rod length 13mm~50mm full range of specifications, nonstandard length customization on demand, drilling applicable plate thickness 2~5mm Packaging: 25kg export cartons, full pallets wrapped with film, supports neutral export packaging, private-label customization
Read MoreMetal screw selection
When comparing suitable metal fastening screws, review the drilling or tapping method, thread profile, screw length, point style, head and drive, coating, and compatibility with the joined materials. These details matter more than a general label such as metal text screw.
| Criterion | What To Check | Why It Matters | Buyer Tip |
|---|---|---|---|
| Self-drilling point or self-tapping thread | Confirm whether the screw must drill its own hole in metal or fasten into a pre-drilled hole. | A self-drilling metal screw saves a drilling step, while a self-tapping screw may work better when hole size and alignment are controlled separately. | Ask: Is the joint metal-to-metal, metal-to-wood, or already pre-drilled? |
| Base material and thickness range | Match the screw type to the steel sheet, aluminum, timber support, or other substrate in the assembly. | Thin sheet, thick steel, and timber backing place different demands on the drill point, thread form, and pull-out resistance. | Provide the material stack-up and ask which screw style suits that exact combination. |
| Head style and drive recess | Compare hex washer head, countersunk head, pan head, or other head forms against the installation surface and tool access. | The head affects clamping area, flush finish, tool engagement, and how easily installers can drive the screw without cam-out. | Ask: Should the head sit flush, clamp a washer, or remain exposed for service access? |
| Coating and corrosion exposure | State whether the screw will be used indoors, outdoors, on roofing panels, or near moisture or chemicals. | Coating choice affects corrosion resistance and compatibility with the sheet or panel finish. | Ask which surface finish is suitable for the exposure conditions and whether sample testing is recommended. |
| Sealing washer requirement | For roofing or exterior sheet metal, confirm whether an EPDM or similar washer is needed under the head. | A metal screw without the right washer may clamp the panel but fail to seal the penetration against water. | Ask: Does this fastening point need weather sealing, or is it only a structural or interior fixing? |
The key distinction is drilling method. A self-drilling screw has a drill-point designed to penetrate the material as it is driven, while a self-tapping screw forms threads in a prepared hole or an opening made by another process. Choosing the wrong type can cause poor thread engagement, excessive installation effort or damage to the panel.
Also check the joint rather than choosing by screw length alone. The length must provide adequate engagement in the supporting material without leaving an unnecessary point exposed, and the head must match the required clamping surface, tool access and finished appearance.
Start with the assembly: metal-to-metal, metal-to-wood or metal panel to a pre-drilled support. Identify the thickness and hardness of each layer, then confirm whether the screw must drill through the outer layer or only form threads in an existing hole. A roofing or exterior panel may also need a head and washer arrangement that controls water entry and distributes clamping force.
Choose the thread and point for the support material. Fine or coarse thread is not an interchangeable cosmetic choice; it affects how the screw engages the substrate and how easily it can strip or loosen. For thin sheet, excessive driving force can enlarge the hole, while an unsuitable point can fail to penetrate or leave inadequate thread engagement.
Match the head and drive to the installation. Hex or washer-head designs can suit applications needing visible clamping and tool access, while a countersunk head is intended for a flush surface where the material can accept the countersink. Do not substitute a flush-head screw for a panel fastening application without checking seating and load distribution.
Finish the specification with the service environment, required quantity, packaging and any sample or inspection expectations. For an inquiry, send the material combination, thickness range and intended application, along with a drawing or photograph if the existing hole, head seating or clearance is unusual.
| Criteria | Importance | Description | Example Options |
|---|---|---|---|
| Drilling method | Often the first decision | Choose between a screw that drills its own entry hole and one that taps into a prepared hole. The wrong choice can slow installation or damage the metal. | A steel support without a pilot hole may call for a self-drilling point; a prepared hole may suit a self-tapping thread. |
| Joined materials | Critical for thread engagement | Metal-to-metal, metal-to-wood and sheet-to-frame assemblies load the screw differently. The receiving material determines the suitable point, thread and length. | A roof panel fixed to steel is not specified the same way as a metal bracket fixed into timber. |
| Head and seating style | Important for clamping and appearance | The head must match the surface and load requirement. A washer or hex head can spread clamping force, while a countersunk head is used where a flush finish is required and the material can accept it. | Visible panel fastening may use a head that clamps broadly; a flush assembly may need countersinking. |
| Length and engagement | Important but often misunderstood | Length should be selected from the full stack thickness and required bite in the support, not by guesswork. Too little engagement can loosen; too much length can protrude or interfere. | A screw passing through a panel and into a frame should be checked against both layer thickness and clearance behind the frame. |
| Coating and service environment | Depends on exposure conditions | Finish selection should reflect indoor, outdoor, damp or corrosive surroundings, as well as appearance requirements. Confirm any project-specific coating or inspection expectations before ordering. | An indoor cabinet bracket and an exterior metal panel may need different surface finishes. |
Related Options
For a metal panel fixed to a steel frame, the main priority is matching the point and thread to the panel and support thickness while maintaining reliable head seating. For a pre-drilled metal assembly, thread engagement and hole fit may matter more than drilling capability.
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No. A self-drilling screw has a drill point that cuts its own entry hole, while a self-tapping screw forms threads in a pilot hole or prepared opening. For metal work, this difference affects installation speed, hole quality and thread engagement.
Confirm the sheet thickness, the backing material and whether the screw will clamp one sheet or pass through multiple layers. Thin metal can strip or distort if the point, thread or driving torque is not suited to the assembly.
Sometimes, but it should not be assumed. Metal-to-metal joints often need a point and thread suited to steel thickness, while metal-to-wood fastening needs enough thread form and length to hold in timber without splitting or poor grip.
Not automatically. Strength depends on proper engagement in the supporting material, correct hole fit, head seating and the condition of the substrate. An overlong screw can leave an exposed point, interfere with nearby parts or add no useful holding value.
Send the joined materials, thickness range, application, required head style, drive type, coating preference and whether the hole is pre-drilled. A drawing, sample photo or current screw size helps clarify seating, clearance and replacement requirements.
Please provide the joined materials and their thicknesses, the application or assembly drawing, and whether the hole is pre-drilled or the screw must drill its own entry hole.
