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Farmer Boy 5mm Diamond Braid Full Break Tests

Last updated January 12, 2025.

# Complete Farmer Boy Diamond Braid Breaktests

# Main Test

Below are the full 56 break tests of Farmer Boy 5mm diamond braid polyester cord. The first 40 tests were measured with a LineScale 2 on Peak Fast mode, with soft shackles connecting directly to the dynamometer. Tension was pulled by a single person per test on a 15:1 pulley system with 3" SMC pulleys. Samples were between 2 and 3 meters long, and had a figure 8 knot terminating any end not being tested (on both sides for the bend tests, on one side for the device tests). The final 16 tests were done on Balance Community’s break test machine, reading at 500 Hz, which Jerry Miszewski generously let us use for testing.

The cord in this test was about 2 years old and heavily used. Offcuts with notable abrasion spots were avoided where possible, although there was likely significant variation in wear across different test samples. The cord was broken because it was deemed due for retirement, and so represents conservative strength values for used cord.

For full discussion of Farmer Boy, see the main post.

Break TypeSample NumberBreaking Strength (kN)Comments
8 to 812.21Broke in middle
8 to 822.44Broke in middle
8 to 832.20Broke in middle
Alpine Butterfly Bend12.10Broke at knot
Alpine Butterfly Bend22.18Broke at knot
Alpine Butterfly Bend32.4Broke at knot
Double Sheet Bend (Yosemite Finish)12.22Broke at knot
Double Sheet Bend (Yosemite Finish)21.98Broke at knot
Double Sheet Bend (Yosemite Finish)32.14Broke at knot
Releasable Double Sheet Bend12.15Broke at knot
Zeppelin Bend12.19Broke at knot
Zeppelin Bend22.02Broke at knot
Zeppelin Bend32.11Broke at knot
Micro Trax11.76
Micro Trax21.54
Micro Trax31.51
Doubled Micro Trax12.28
Doubled Micro Trax22.38
Doubled Micro Trax32.15
Mini Trax11.76
Mini Trax21.54
Mini Trax31.51
Doubled Mini Trax12.16
Doubled Mini Trax22.24
Doubled Mini Trax32.01
Roll N Lock11.94
Roll N Lock21.91
Roll N Lock32.13
Doubled Roll N Lock11.93Broke notably lower than single wrapped
Doubled Roll N Lock21.79Broke notably lower than single wrapped
Doubled Roll N Lock31.82Broke notably lower than single wrapped
Handled Ascender11.06
Handled Ascender21.13
Handled Ascender31.24
Chained Handled Ascenders11.662 in line connected by carabiner
Chained Handled Ascenders21.692 in line connected by carabiner
Chained Handled Ascenders31.792 in line connected by carabiner
Tibloc10.99Slips, tearing outside
Tibloc21.79*Slips, tearing outside - this test likely loaded the backup rope, leading to artificially high result
Tibloc31.00Slips, tearing outside
Capstan to Capstan14.39
Capstan to Capstan24.04
Capstan to Capstan34.22
Duck12.44
Duck22.46
Duck32.57
Ropeman 112.11Minor Slippage
Ropeman 121.78Slipped around 1.6
Ropeman 131.96
Spoc12.41
Spoc22.39Desheathed then broke
Spoc32.33
Nite Ize CamJam XT12.87
Nite Ize CamJam XT22.74Slipped before breaking
Nite Ize CamJam XT32.80Broke at 8 knot
4 Wrap Prusik31.26Made of Farmer Boy, Slips

# Other Known Testing - Alonso’s Test Videos

Alonso’s Figure 8 tests show values as high as 3.10 kN for 5mm diamond braid, indicating either that he was using a different brand of cord, or that his cord was less used than mine. My best guess is that my cord was simply more used than his. In the capstan tests, my cord tested as high as 4.04 kN, indicating higher “true” breaking strength in the middle, less used sections of cord. In the devices tested, our results are roughly similar, with minimum values with about .1 kN, or about 5%, across tests. It appears the breaking strength in devices was not highly affected by the wear on the cord.

His tests are spread out across two videos, both below. The first breaks 5mm and 6mm diamond braid in a Petzl Micro Trax and Pro Trax, and the second breaks the same cords in the CT Roll N Lock as well as a figure 8.

# Micro Trax and Pro Trax

### Roll N Lock and Figure 8

# Edits

I will be trying to keep this page up to date with feedback and new information, and will keep track of edits as I make them here.

  1. Added additional break test results and discussion (10/19/22)

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