USITT Testing Results

Load Lab
Test Results - Destructive Test Data from the USITT National Conference
March 31-April 2, 2010

Destructive Testing Web Site
Created by Delbert L. Hall, Ph.D.
ETCP Certified Rigger - Theatre and ETCP Recognized Trainer

Load Lab Home Test Data Testing Equipment Support/Sponsors

Disclaimer: This site contains the currents results of ongoing research and is not a finished presentation of findings. The information on this site may be the results of a small sample of tests and are NOT conclusive evidence of anything – they are just my results. Take them for what they are. Any conclusions drawn from these results are yours and not are necessarily mine. Go the Load Lab Home to read the complete disclaimer.

As part of the USITT National Conference, I set up the LoadLab rig on the Stage Expo floor and performed destructive tests on many different materials over the three days of the Expo. Although the numbers of samples for each test was very small (mostly only one sample) the results of the tests were of interest to many of the observers, and probably to many others, which is why I am posting them here. Enjoy reading them and drawing your own conclusions from the results.

Test Group #1 - Tensile tests on terminations in 1/8" GAC
Minimum Rated BS: 2000 lbs

Test #1A - Termination made with two cable clips – both installed properly
BS: 2047 lbs

Test #1B - Termination made with two cable clips – both installed backward
BS: 1647 lbs

Test #1C - Termination made with two cable clips – clip closest to thimble installed properly, clip farthest from thimble installed backwards
BS: 1651 lbs

Test #1D - Termination made with two cable clips – clip closest to thimble installed backward, clip furthest from thimble installed properly
BS: 2166 lbs

Test #1D - Flemish eye
BS: 1879 lbs

Test #1E - Flemish eye
BS: 1785 lbs

Test #1F - Flemish eye
BS: 1798 lbs

Test #1G - Circus hitch around 2" OD pipe
BS: 1828 lbs

Test #1H - Properly swaged sleeves
BS: 2127 lbs

Test Group #2 - Tensile tests on Shackles , Quicklinks, VERLocks, and Gripples

Test #2A - 1/4" Imported shackle – loaded properly
BS: 6085 lbs

Test #2B - 1/4" Imported shackle – side loaded
BS: 4669 lbs

Test #2C - 1/4" Imported shackle – side loaded
BS: 4544 lbs

Test #2D - 1/4" Imported Quick link
BS: 5664 lbs

Test #2E - VERLock w/ 1/8" GAC
BS: 1559 lbs

Test #2F - Gripple w/ 1/8" GAC
BS: 1803 lbs

Test Group #3 – Proof load test and tensile test of ¼" Alloy Shackle (Domestic)
WLL: 1500 lbs

Test #3A - Proof Load of 3000 lbs (2x WLL)
Height before test: 1.786" - Height after test: 1.789"
Note: virtually no elongation

Test #3B - Tensile test

BS: 10,760 lbs

Test Group #4 – Shop-built scenery hangers (by Alex Weston)

Test #4A
BS: 1312 lbs
Note: 1x3 split

Test #4B
BS: 1412 lbs
Note: 1x3 split

Other hanging hardware

Test #4C - Trim chain with aluminum "dog clips"
BS: 555 lbs
Note: Dog clip failed

Test Group #5 – ¼" GAC, Trim Chains around batten and terminated with ¼" shackle

Test #5A - 1/4" Grade 30 Proof coil chain – shackle terminated back to thimble
BS: 7489 lbs
Note: Cable failed

Test #5B - 1/4" Grade 30 Proof coil chain – shackle terminated into trim chain
BS: 6860 lbs
Note: Chain failed where link was captured under shackle

Test #5C - 1/4" Grade 30 Proof coil chain – wrapped around batten (WLL 1300 lbs)

BS: 9725 lbs

Test #5D - 1/4" STC Trim Chain by SECOA – single piece of chain (not wrapped)
WLL: 3,250 lbs
BS: 14,000+ lbs
Note: Chain stretched but did not break

Test Group #6 – ¼" GAC
Minimum Rated BS: 7000 lbs

Test #6A - 1/4" GAC terminated with a bowline
BS: 4608 lbs
Note: Cable failed at bowline

Test Group #7 – 1/8" GAC
Minimum Rated BS: 2000 lbs

Test #7A - 1/8" GAC terminated with a bowline
BS: 1092 lbs
Note: Cable slipped at bowline

Test Group #8 – 1" Ratchet Nylon Ratch Strap
Minimum Rated BS: 1300 lbs

Test #8A
BS: 1580 lbs
Note: Broke at stitching

Test #8B
BS: 1608 lbs
Note: Broke at stitching

Test #8B - Ratchet Strap partially cut
BS: 1214 lbs
Note: Broke at cut

Test Group #9 – Prusiking knots around ¾" dia. Multiline II

Test #9A - Snub knot (four wraps) made with 3/8" double-braided rope
BS: 958 + lbs
Note: End of stroke on cylinder reached

Test #9B - Prusik made with 3/8" double-braided rope (sunday)

BS: 1431 + lbs

Note: Slide slightly, but held – end of stroke reached

Test #9C - Prusik made with 1/8" GAC
BS: 3195 lbs
Note: Multiline II cut by sunday

Test Group #10 – 3/8" Turnbuckles
WLL: 1200 lbs

Test #10A - Imported forged turnbuckle (with jaws – cotter pins held pin in place)
BS: 6173 lbs
Note: Jaws spread and pin came out

Test #10B - Domestic forged turnbuckle (with jaws & bolts with nuts)
BS: 8261 lbs
Note: Threaded rod failed

Test #10C - Imported forged turnbuckle (with closed eyes)
BS: 7040 lbs
Note: Threaded rod failed

Test Group #11 – 3/16" Tech 12
Minimum BS: 5000 lbs

Test #11A - Rope splices into a loop (splice made by inserting tail 10" into core of rope)
BS: 7507 lbs
Note: Rope failed away from the splice

Test Group #12 – Lighting C-clamps
WLL: unknown/600 lbs

Test #12A - Cast iron C-clamp (WLL: unknown)
BS: 2426 lbs

Test #12B - Cast iron C-clamp (WLL: unknown)
BS: 2651 lbs

Test #12C - Mega-Clamp Aluminum C-clamp (WLL: 600)
BS: 4833 lbs

Note: All clamps broke at the same place on the C-clamp

I hope to add some photos and videos in the coming weeks.
Thanks to Steve Rees, Jonathan Deull, and Samantha Sayers for helping run the destructive testing sessions at the conference.