Riveting in Sheet Metal: An Overview(manufacturing metal parts Renee)
- source:YESCOM CNC Machining
What is a Rivet?
A rivet is a mechanical fastener that consists of two main parts - a smooth cylindrical shaft and a head. The shaft is inserted through holes in the materials being joined. The excess shaft is then flattened into a second head with a riveting tool, creating a permanent joint. The rivet heads on either side clamp the materials together tightly.
Common Types of Rivets
Several types of rivets are commonly used with sheet metal:
Solid/Round Head Rivets: As the name suggests, these have a solid round head on one end. The other end is flattened during installation. These provide high clamping force but the heads can interfere in some applications.
Countersunk Head Rivets: These have a flat counterbore under one head so it sits flush with the material surface. The other end is dome shaped when set. Countersunk rivets minimize protruding heads.
Blind Rivets: These are tubular rivets that can be installed from only one side - ideal for situations where you only have access to one surface. Blind rivets use a mandrel that is pulled to flare the tail.
Self-Piercing Rivets: Similar to blind rivets, these cut their own hole before flaring to lock in place. No pre-drilled hole is required. Often used to join dissimilar metals.
Drive Rivets: These have large domed heads on both ends. They are quickly installed using only hammer blows rather than a riveting tool.
Benefits of Riveting Sheet Metal
Compared to other joining techniques, riveting sheet metal offers numerous benefits:
- Can be highly automated for efficient large-scale production. Installation is fast.
- Produces strong, permanent joints while allowing some flexibility in the material.
- Only access to one side is required for blind or self-piercing rivets.
- Minimal surface prep - only drilling holes. Does not require cleaning like welding.
- Uses relatively inexpensive materials (rivets) compared to welds or adhesives.
- Simple technique that requires basic equipment. Easy to inspect and repair.
- Joins disparate materials like plastics and composites unlike welding.
- Adds negligible weight compared to bolts or screws.
- Produces no heat damage or distortion.
Riveting Tools and Equipment
Installing rivets requires just a few special tools:
Rivet Gun - Applies pulling force to set the rivet. Can be pneumatic, hydraulic, battery powered, or even hand operated types.
Bucking Bar - A steel bar placed against the back side of the rivet. Absorbs force from the rivet gun to flare the tail.
Drill & Drill Bits - Required to pre-drill rivet holes. Hole size should match rivet diameter.
Rivet Sets - Tip tools to flare the rivet tail and conform the head shape. Use with rivet gun.
Hammer & Dolly - Can set drive rivets and do some final shaping of rivet heads.
Hole Punches - Quick alternative to drilling for repetitive hole spacing.
Rivet Spacing Gauges - Ensure correct spacing for row of rivets.
Personal protective equipment like eye protection, gloves, and hearing protection are also recommended.
Best Practices for Riveting Sheet Metal
Follow these proven techniques for successful rivet joints in sheet metal:
- Hole dimensions should match rivet size - usually ~1/64" over rivet diameter. Avoid undersized holes.
- Sheet materials must clamp together tightly with no gaps before installing rivets. Use clamps or temporary fasteners.
- Apply heavy pressure with bucking bar and rivet set/gun when setting rivets. This CNC Milling CNC Machining