Howell Forward-Retention Test-Device (optional)
Howell Forward-Retention Test-Device (optional) US$18,000
Terms: 1/2-deposit upon order; 1/2 upon shipment, FOB Stowe, Vermont USA.
Available 60-days after placing deposit.
This is the mother of all ski binding test devices.
Howell Forward-Retention Test-Device is an optional, dynamic-impact test-device that demonstrates, validates, and calibrates the special forward-retention characteristics of Howell SkiBindings for elite-skiers, extreme skiers, and racers. This test device is optional: it is not required for Howell SkiBindings. 'But it's an awesome way to conduct maker-research on ski-binding retention and to optimally-set forward heel retention without extreme over-adjustment of the forward heel release function (1).
Retention Does NOT Equal Release.
Proper retention-function of a ski binding is a function of ski binding design, not (completely) release.
Description: Howell ACL-Friendly Fixture (included with this purchase, see Catalog; also sold separately) is rigidly connected to the top of the Howell Forward-Retention Test-Device 'lower tower'. The base of the lower tower is connected to a 400-pound cast-in-place concrete footing (concrete and concrete-footing not included — but it's easy to pour Ready-Mix directly into a hole that's dug in the ground, as shown in the image) by four (4), 2cm-Ø cast-in-place stainless steel lag bolts (connection-instructions; bolt-positioning-template; and bolts are included). An 'upper tower' (not shown in photo), made of aluminum channel, is suspended 4.5-meters above the top of the lower tower to hold the fulcrum of the pendulum-arm that is 5.5-meters in overall length. The pendulum-arm is made of super-low-stretch, 1200-pound-test, sailing-line. The 'ram' (mass) of the stainless steel pendulum is 32cm long x 8cm-Ø, and weighs 14kg (30-pounds). An aluminum-channel 'test-ski' (with bolted stainless steel tip-plate) is affixed to the tip of the 'test-ski' (skis & bindings not included), aluminum-channel 'test-ski' is included). The tip of the test-ski is adjustably pre-loaded by a 1-meter long spring — toward the upside-down "surrogate-metallic-skier's" center-of-gravity (the magnitude of the pre-load is adjustably-specified by Howell SkiBindings). The exact height of the pendulum-ram (mass) is micro-adjustable (vertically) to assure that the center of the ram contacts the center of the tip of the test-ski at the low-point of the pendulum's arc (the length of the pendulum is not changed — the height of the fulcrum is micro-adjustable). The vertical adjustment of the pendulum's fulcrum compensates for various stand-heights and ramp-angles of bindings (ski-binding ramp-angle varies according to boot sole length when ramp-angle does not equal zero). A large, easy to read stainless steel-protractor is rigidly-connected to the 'upper tower' to measure the starting angle of the pendulum.
Initially, each ski-binding heel is adjusted to the Howell-specified quasi-static forward-release level (using standard forward-release measuring equipment that is not included — such as, for example, the currently-excellent Vermont Release Calibrator that's available through Vermont Safety Research in Underhill, Vermont). The ski (together with the aluminum-channel test-ski that's attached to the ski) is then attached to the ski-boot (boot not included) by the bindings, which boot is already attached to the Howell ACL-Friendly Fixture, which fixture is already bolted to the top of Howell Forward-Retention Test-Device's lower-tower (see photo).
The ram of the pendulum is then raised along an arc to an initial 'starting-angle' — then released — to strike the tip of the test-ski*. The initial starting-angle of the pendulum-ram is specified by Howell SkiBindings. The heel can then be tuned to a 'special dynamic-retention setting' that's derived by this dynamic test method. None of this dynamic-testing is mandatory for Howell SkiBindings: this method is optionally-suitable for elite-skiers, extreme-skiers, and racers who might like to fine-tune forward retention and explore the differences in forward retention that are offered by different ski binding designs.
350-pounds including wooden shipping crate. Shipping within North America is included in the price. For shipping beyond North America, please contact Howell SkiBindings by email for special shipping price and logistics [firstname.lastname@example.org].
This is the mother of all ski binding test devices (1, 2).
FLAT-OUT SKIING CONFIDENCE.
It was inevitable.
(1) For release measurements (including torsional, toe — and forward, heel), we recommend the Vermont Release Calibrator that's available through Vermont Safety Research in Underhill, Vermont, USA. Again, release does not equal retention. Retention is governed by ski binding design, not (completely) by settings. This device tests retention to measure forward anti-pre-release — not release.
(2) This optional dynamic-impact test device is not a substitute for the functional inspection of the special lateral heel release of Howell SkiBindings relative to the complete ski-boot-binding system. For the optional testing of the function of the special lateral heel release of Howell SkiBindings, please see the Catalog for the Howell ACL-Friendly Fixture.
* SPECIAL CAUTIONARY NOTE: A specially-configured tether (supplied) is necessary to capture the released-ski upon impact. The tether and instructions are supplied in order to mitigate collateral damage upon release of the ski — especially when releasing at elevated settings (Howell 888 WC Racing max setting = DIN 26. CAUTION FOR RACERS AND EXTREME SKIERS ONLY.).
Howell SkiBindings company is against (a) ski waist widths greater than 87mm AND (b) all 'pin-binding's' (except new Trab TR2) — due to (a.i) their association with a new type of skiing-injury: severe, high-energy tibia-plateau fractures, severe tibial-tuberosity fractures, cumulative miniscus-damage, and MCL-rupture; and (b.i) due to high-energy, spiral-tiba-fractures. Both new types of skiing injuries are the fastest-growing categories of injuries in skiing — matching the growth of fat-skis and pin-bindings. The high-energy nature of the new types of skiing fractures involve many multiple-fragments, difficult surgical reconstruction, and 10 to 15-months of aggressive rehabilitation. Fat skis (on firm snow) and pin-bindings (in any snow) ((except the new Trab TR2)) — are a serious problem for the sustainability of our beautiful sport: the ISO standards on pin-bindings are knowingly wrong: they are about money; political-engineering; patent portfolios; and must be immediately changed to reflect human-biomechanics, not just manufacturing-tolerances. References: (1) Dominik Heim, MD; SITEMSH-Japan, 2016. (2) Zorko; Nemec; Matjacic; Olensek; Alpine Skiing Simulations Prove Ski Waist-Width Influences Knee Joint Kinematics; ISSS-Innsbruck, Austria, 2017. (3) Stenroos; Pakarinen; Jalkanen; Mälkiä; Handolin; Tibial Fractures in Alpine Skiing and Snowboarding in Finland: A Retrospective Study on Fracture Types and Injury Mechanisms in 363 patients; Scand J Surg Off Organ Finn Surg Soc Scand Surg Soc., Sept 2015, doi:10.1177/1457496915607410. (4) Improved Short Term Outcomes in Tibial Plateau Fractures of Snow Sports Injuries Treated with Immediate Open Reduction Internal Fixation; Janes, MD; Leonard, MSPH; Phillips, PA-C; Salottolo, MPH; Abbott, MD, Bar-Or, MD; ISSS-Innsbruck, Austria, 2017.