Petzl Am'D Spinball

Am'D Spinball

Name:Petzl Am'D
Sub Item:Spinball
Category:other locking
Locking Type:assisted
Unlock Style:press-and-twist
Sleeve Rotation:120° (unlocked) | 120° (maximum)
Shape:asymmetric D
Nose Guard:none
Gate Shield:relieved: blocked
Weight:71 g
Dimensions:Length: 111 mm
Width: 63 mm
Gate Opening: 22 mm
Strength Ratings:Major Axis: 28 kN | Minor Axis: 7 kN | Gate Open: 8 kN
Other Markings:Forged: PETZL Am'D Pat. | (ratings) CE0197
Injection Molded: (Petzl oval logo) SPINBALL PATENTED (fingerprint texture)
Stamped: 031740
Batch Marking Location:spine-exterior-left
Collection Criteria:★ Mechanically Interesting
★ Historically Interesting or Iconic
Summary:manual version of ball-lock
Description & Commentary:

The Petzl Am'D was (and still is) an iconic large D carabiner, fully featured for its time with keylock gate latch, gate relief hole, slight asymmetric (offset) shape. Offered in many different locking sleeves, this model uses the Petzl Spinball, a manual twist + button lock mechanism.

From the unlocked position, the yellow sleeve is manually rotated about a third of a turn and engages a spring-loaded green button which protrudes through a hole in the sleeve. Depressing the button (or ball) and rotating the sleeve will unlock the carabiner. The rotation of the sleeve is entirely manual and not spring-powered, permitting the carabiner to remain in the unlocked position until it needs to be secured - much like a traditional screw lock carabiner.

Most modern triple-action carabiners use two spring-powered locks (full autolocking), whereas the Spinball uses a manual lock (the spin) in conjunction with a single autolocking mechanism (the ball).

To unlock, climbers typically depress the button with the thumb or middle finger, depending on carabiner orientation and which hand is used. The opening in the locking sleeve is positioned about a third of a rotation from the unlocked position (actually 3/8ths turn or 135 deg), and may be rotated in either direction to unlock. The button is positioned 90 degrees off of the sleeve opening, 135 degrees from the nose. If grasping the carabiner from the spine side it is generally easier to unlock by depressing the button then continue pushing the sleeve in the same direction with one or two motions - taking the long way around the gate.

Note that the Ball Lock sleeve unlocks after about a 45 deg rotation - the longer minimum rotation of the spinball seems appropriate considering the manual aspect of this mechanism. Spinball was introduced in 1998, after Ball lock (1997).

I appreciate manual locking carabiners, climbing almost exclusively on them for recreational tree climbing. Even so, I prefer a metal-sleeved screw lock carabiner, as I expect it would be a bit stronger at resisting force on the gate face - I would be concerned about the plastic sleeve deforming under a gate face load. That said, this is one of my favorite carabiners in the collection, and I wish we could get a re-release using a metal sleeve and a lightweight hot-forged carabiner body - for now we will have to settle for the Edelrid Permalock.

The relief hole in the back of the gate is partially blocked by the locking sleeve, but the interior of the sleeve tapers outwards in a conical shape which should help as well.

Relevant Patent:EP0826890A1