Strength to Weight Comparison of Spring Loaded Camming Devices

1
Strength to Weight Comparison of Spring Loaded
Camming Devices

• A Presentation by Matthew Looft

2
So, Whats an SLCD?

• Used in Rock Climbing as Protection
• Placed on Lead or used in Anchor Construction as
  solid points of contact with the rock.
  
• Clean form of Climbing.
• Considered to be Active, as opposed to
  Passive.
  

3
and, How do They Work?

• Downward Force is transferred into a
  side-directed outward force.
  
• Cam shape is based off of a logarithmic curve
  to maximize range.

4
What is Being Compared?

• Strength
• kN or Kilonewtons
• Measurement based on the force (1kN) required to
  change the inertia of an object with a mass of
  224.81 lbs.
  
• (Metric/Standard conversion error)
• Weight
• Weight of each device, in Grams
• Heavier with larger Range or Size
• Intuitively, Heavier with Increased Strength

5
Some Other Things to Consider.

• Cam Range
• Size range of the crack that the cam can fit
• Number of Cams it takes to fill an entire Range
• Single- or Co-axial
• Single or Double Stemmed
• Flexible or Rigid
• Materials
• Price! (Dirt Bag Climbing Culture)

6
(No Transcript)
7
Just a Start

• Includes 5 Manufacturers
• 10 Different Models
• Over 70 Sizes/ Points
• Too Confusing for the Presentation
• Too Much Information
• Take Too Long to Analyze All of It
• Try a Simplified Model
• Colorado Custom Hardware Aliens, Sizes 1-6 of 8
• Black Diamond Equipment Micro Camalots, 6 Sizes,
  .1-.75, of 8

8
(No Transcript)
9
Aliens and Micro Camalots ComparedStrength to
Weight

• X-axis Weight in Grams
• Y-axis Strength in Kn

• Increased Weight With Increased Strength
• Follow almost Parallel Patterns, but CCH Aliens
  are stronger (1.5-2 kN) in the 4 smaller sizes.

10
(No Transcript)
11
Aliens and Micro Camalots ComparedRange to Weight

• X-axis Range in millimeters
• Y-axis Weight in grams

• Similar points for first three Ranges/ points
• Last three Ranges, CCH Aliens are lighter (15-30
  g), for comparable size, than the Micro Camalots

12
(No Transcript)
13
Aliens and Micro Camalots ComparedStrength to
Range

• X-axis Range in millimeters
• Y-axis Strength in Kilonewtons
• _____________________________________
• The lines follow a similar, almost parallel,
  model
  

• The CCH Aliens are Stronger in the four smaller
  Ranges, and just as strong as in the two larger
  Ranges, as the BD Micro Camalots

14
How is this Useful? (Conclusion)

• The CCH Aliens are Stronger and Lighter by Range
  than BD Micro Camalots
  
• CCH Aliens are Stronger by Weight than the BD
  Micro Camalots
  
• Is the CCH Alien the superior Device?

• Maybe
• Other Factors
• Price... Aliens are Cheaper
• Width Aliens are Narrower- Aid!
• Axles Micro Camalots have two, only micro cam
  placed passively!

15
Go Climbing!