Climbing Cam Placement, Use, and Maintenance

You have to know how a Cam is used to know which Cam to select

Climbing Cam Placement, Use, and Maintenance

Spring-loaded camming devices (SLCDs), commonly called cams, are essential pieces of traditional climbing protection. They work by converting outward pulling force into pressure against the surrounding rock, allowing climbers to protect cracks, fissures, and irregular features where other types of protection may be unsuitable.

Although cams are relatively easy to place, their effectiveness depends on selecting the correct size, understanding the placement geometry, evaluating the rock, and ensuring the device is positioned to withstand the expected direction of loading. Proper inspection and maintenance are also essential for keeping cams reliable over years of use.

Sizing Cams

Sizing comes with time.  As you play with the cams, you will get better and better at selecting the right sized Cam the first time.  Climbers use their fingers and hands as a physical and tactile reference to estimate crack widths and select the correct spring-loaded camming device (cam) without having to constantly look at the gap.

How Fingers and Hands Relate to Cam Sizes

As climbers gain experience on rock, they map specific hand and finger geometries to standard cam sizes.  Obviously, different sized hands will size Cams differently. 

• Tight/Fingertip Cracks (Micro-fingers)

  • A crack that only accommodates the tips of your fingers corresponds to small finger cams

  • Look for sizes around 10 mm to 15 mm 

  • #0.1–#0.3 Camalots

• Standard / "Goldilocks" Finger Cracks

  • Look for sizes around 15 mm to 24 mm 

  • #0.3 Camalot

• Loose Fingers / Thin Hands Transition

  • Look for sizes around 24 mm to 33 mm 

  • #0.4 or #0.5 Camalots

  • Big Finger: #0.5

  • Loose Finger: #0.4

• Hand Jams / Cupped Hands

  • A crack that fits a cupped hand or a ring lock maps directly to mid-sized hand cams 

  • #0.75, #1, #2, or #3 Camalots

  • Practice with these and try using different fingers or combination of fingers to help size your cam

    • 4 Fingers side-by-side: #3 Camalot

    • 3 Fingers side-by-side: #2 Camalot

    • 2 Fingers side-by-side: #1 Camalot

    • 1.5 Fingers: #0.75 Camalot

• Fists and Stacked Hands

  • A crack that swallows a full fist or stacked hands corresponds to larger units

  • #4 Camalot or larger

Why Fingers and Hands to Help Select a Cam

• Instead of stopping, pulling a cam off your harness, and trying it in the crack multiple times, you can gauge the width immediately by feeling or jamming the crack with your hand or fingers first

• When climbing above your gear or in awkward body positions where you cannot easily see the crack, your sense of touch tells you which unit to reach for on your rack

Cam Sizing and Range

Every cam is designed to operate within a specific range of crack widths. Selecting the correct size is important because a cam must have enough expansion remaining to engage the rock while avoiding excessive retraction.

Cam manufacturers typically provide minimum and maximum placement widths, often marked on the device or listed in its specifications. These indicators help climbers determine whether a cam is within its intended operating range.

When choosing a cam, look for a size that allows the lobes to engage comfortably without being nearly fully retracted or excessively expanded. Avoid placements at the extreme ends of the usable range whenever a better-fitting device is available.

Under-camming occurs when a cam is too small for the crack and its lobes are near or beyond their maximum expansion. Over-camming occurs when a cam is too large for the crack and its lobes are excessively retracted, potentially leaving insufficient expansion available to accommodate movement or loading.

A properly sized cam should have room to expand and contract while remaining securely engaged. When a crack varies in width, consider whether the cam could move into a narrower or wider section under load.

How to Place a Cam

A cam should be placed in a secure section of rock where all lobes can make solid, stable contact with the surrounding crack walls.

To place a cam, first select a device that fits the available crack width. Pull the trigger to retract the lobes, insert the cam into the crack, and release the trigger so the lobes expand against the rock. Position the cam so that its stem and sling are oriented as close as practical to the anticipated direction of loading.

Before relying on the placement, visually inspect the cam to confirm that all lobes are engaged, the device is within its usable range, and the surrounding rock is solid. Check that the cam is not resting against a loose flake, positioned too close to an edge, or likely to move into a less secure position.

A properly placed cam should sit securely without excessive retraction or expansion, with the lobes making consistent contact against suitable rock surfaces.

Cam Placement Anatomy

A cam placement is formed by the interaction between the cam's lobes and the surrounding rock. The lobes provide the contact surfaces, while the camming geometry converts outward loading into pressure against the crack walls.

A good placement generally has:

• All lobes making stable contact with solid rock

• The cam positioned within its recommended operating range

• Adequate depth to prevent the device from pulling out

• Sufficient clearance for the lobes to expand and rotate under load

• A stem orientation that minimizes unwanted leverage

• No loose flakes, fractured edges, or obstructions interfering with the device

In parallel-sided cracks, a conventional cam can often achieve relatively symmetrical contact. In flared cracks, pin scars, and irregular constrictions, the contact may be uneven. Offset cams or other specialized devices can sometimes provide better engagement in these situations.

A placement is considered marginal when the cam has limited contact, is near the edge of its range, or depends on questionable rock. A placement is unacceptable when the lobes cannot engage securely, the device is outside its operating range, or the surrounding rock is unsuitable to support the load.

Placement Direction

Cams are designed to resist outward loading, but the direction of the force applied to the device can significantly affect its security.

Ideally, the stem should point toward the expected direction of pull, allowing the cam to load in a controlled manner. When the direction of loading is substantially different from the stem's orientation, the cam may experience unwanted leverage, rotation, or movement.

This is particularly important in horizontal cracks, traverses, and placements where the rope may pull sideways or upward. Flexible-stem cams can accommodate some movement and changes in loading direction, while rigid-stem designs may be more vulnerable to unfavorable leverage in certain placements.

When placing a cam, consider not only the direction of a potential fall but also how the rope will travel as the climber moves. The placement should remain secure under the anticipated loading direction without allowing the stem to bend against an edge or the cam to rotate into an unstable position.

Walking and Migration

Cam walking occurs when a cam gradually moves deeper into a crack, toward an edge, or into a different position as the rope moves or the climber changes direction.

Walking can result from rope drag, repeated loading and unloading, vibration, movement of the climber, or changes in the direction of force. A cam that initially appears secure may migrate into a narrower or wider section of the crack, potentially reducing its effectiveness or making it difficult to retrieve.

Several techniques can help reduce walking:

• Place cams where the crack geometry limits unwanted movement

• Orient the stem to accommodate the expected direction of loading

• Use appropriate extensions to reduce rope drag and sideways pulling

• Avoid placing cams where the stem or sling can easily be pushed or pulled

• Consider whether the cam could migrate toward an edge or into a constriction

Extending a cam can reduce rope drag and help prevent the rope from pulling the device out of position. However, extensions do not eliminate walking caused by poor placement geometry or movement within the crack.

Rock Quality

The quality and structure of the rock are critical to cam security. A cam relies on the surrounding rock being strong enough to withstand the pressure applied by its lobes.

Granite is often well suited to cam placements when the crack walls are solid and continuous. However, fractured granite, loose flakes, and thin edges can still fail under load.

Sandstone varies considerably in strength. Some sandstone provides excellent protection, while softer or poorly cemented rock may crush, fracture, or break under cam pressure. Climbers should be particularly cautious with shallow placements and placements behind thin flakes.

Limestone can contain pockets, solution features, and irregular cracks that create useful placements but may also conceal weak or fractured rock. The quality of the contact surfaces should be carefully evaluated.

Fractured or loose rock presents a significant hazard regardless of rock type. A cam placed behind a loose block or unstable flake may cause the rock itself to fail, even if the device is correctly sized and positioned.

Always evaluate the rock surrounding the placement, not just the cam's fit. A secure-looking cam cannot compensate for weak or unstable rock.

Inspection and Retirement

Cams should be inspected regularly to ensure that all components remain in safe working condition. Inspection is especially important after heavy use, exposure to dirt or corrosion, unusual loading, or a significant fall.

Check the following components:

• Lobes: Look for cracks, deformation, excessive wear, sharp damage, or other irregularities

• Axles and rivets: Check for damage, looseness, bending, or abnormal movement

• Trigger mechanism: Ensure the trigger operates smoothly and retracts all lobes evenly

• Cables and stems: Look for fraying, kinks, broken strands, corrosion, or deformation

• Springs: Confirm that the lobes return properly when the trigger is released

• Slings and Stitching: Inspect for cuts, abrasion, discoloration, chemical damage, or damaged stitching

A cam should be removed from service if it has structural damage, a compromised sling, damaged cables, malfunctioning components, or any condition that raises doubt about its reliability.

Follow the manufacturer's inspection and retirement criteria. There is no single universal retirement age for all cams; service life depends on the model, usage, environment, maintenance, and manufacturer guidance.

When in doubt, contact the manufacturer or retire the device rather than continuing to use questionable equipment.

Maintenance

Regular maintenance helps keep cams operating smoothly and extends their useful service life.

After climbing in dusty, muddy, or wet conditions, clean the cam according to the manufacturer's instructions. Remove dirt and debris from the lobes, trigger mechanism, springs, cables, and axles.

If the trigger becomes stiff or the mechanism does not operate smoothly, use an appropriate lubricant recommended by the manufacturer. Avoid excessive lubrication, which can attract dirt and interfere with operation.

After exposure to moisture, dry the cam thoroughly before storing it. Pay particular attention to springs, cables, axles, and other metal components where corrosion may develop.

Periodically check that the lobes retract and expand smoothly, the springs function properly, and the trigger cables remain correctly seated. Inspect the sling and stitching for wear or damage.

Store cams in a clean, dry location away from corrosive substances, excessive heat, and damaging chemicals.

Cam Limitations

Although cams are versatile, they are not suitable for every crack or rock feature.

Cams may be inappropriate in:

• Loose or fractured rock that cannot support the pressure applied by the lobes

• Shallow cracks that do not provide adequate engagement

• Very flared cracks where the cam cannot achieve stable contact

• Placements near edges where the device could pull out or become damaged

• Cracks that are too narrow or too wide for the cam's operating range

• Irregular features where the lobes cannot engage consistently

• Placements where the expected loading direction creates dangerous leverage

• Cracks where the cam is likely to walk into an insecure position.

In some situations, passive protection such as nuts, offset nuts, or specialized protection may provide a more suitable option. The best choice depends on the crack geometry, rock quality, and expected direction of loading.

Cams should never be treated as automatically secure simply because they fit inside a crack. Placement quality and rock integrity are always essential.

Cam Placement Examples

Photographs and diagrams are valuable tools for understanding cam placement. Examples should illustrate how the same device can be secure in one position and unreliable in another.

Good placement: All lobes engage solid rock, the cam is within its recommended range, the stem is oriented appropriately, and the device has sufficient depth and clearance to remain secure under load.

Marginal placement: The cam is near the edge of its operating range, has uneven contact, is shallow, or is positioned where movement could reduce its security. Such placements require careful evaluation and may be improved by selecting a different size or location.

Unacceptable placement: The cam is over-expanded or excessively retracted, has inadequate lobe contact, is positioned behind loose rock, or is likely to pull out or become damaged under the expected loading direction.

Illustrations should also show examples of placements in parallel cracks, flared cracks, horizontal cracks, pin scars, and irregular constrictions. These examples help climbers recognize how crack geometry affects cam performance and why placement quality matters more than simply finding a crack that matches the cam's size.

Conclusion

Climbing cams are highly effective pieces of protection when they are properly selected, placed, inspected, and maintained. Understanding cam geometry, placement direction, rock quality, and potential movement helps climbers make better decisions and recognize when a placement may be unreliable.

Developing these skills through qualified instruction, supervised practice, and careful study of manufacturer guidance is an important part of becoming a proficient traditional climber.