SLCD小傳

Spring-Loaded Camming Devices (SLCDs)，在台灣大多數人用Wild Country的產品名：Friends來稱呼（大陸稱之為機械塞）。SLCD的發明在傳攀歷史上可說是劃時代的產物，它的發明讓傳攀活動更加便利、安全。但相較於傳統被動式的岩楔(nut/chock)，SLCD在使用上仍有需多需加注意之處，尤其是其機械部分的保養跟使用，使用時若有疏忽則容易肇生事端。

以下文章譯自Climbing雜誌2011年2月號。

（未經本人同意 ，請勿以任何形式張貼、轉載本文內容）

參考網址：
http://www.climbing.com/exclusive/features/10_things_you_didnt_know_about_camming_devices/

10 Things You Didn't Know about Camming Devices

By Laura Snider

In the three decades since spring-loaded camming devices were invented, they’ve radically transformed the notion of what climbs can be led safely. Here’s a little lore about modern climbing’s most revolutionary piece of protection.

在SLCD問世以來的三十個年頭間，其使用大幅改變攀岩者對先鋒攀登的安全認知。以下是對現代攀岩活動最具革命性的保護裝置的簡略傳記：

1 The essential brilliance of spring-loaded camming devices (SLCDs) is their lobes’ shape, which is described mathematically as a logarithmic spiral. The same curving lines are found naturally in seashells, pine cones, flower heads, and even in the basic form of our own galaxy, the Milky Way. Logarithmic spirals are ideal for camming units because no matter how retracted (or nearly tipped out) the cams are, the lobes contact the rock surface at the same angle. Changing the tightness of the lobes’ spiral can change both the cam’s range and its camming angle. But it’s a tradeoff: Increasing the cam’s angle increases the range, but it also decreases the force exerted by the cam’s lobes on the sides of a crack when a climber weights the device. That means cam manufacturers have to strike a balance between the cam’s range and its holding power.

1. SLCDs的精妙之處在於其以數學中對數螺線概念出發的凸輪狀設計，類似的彎曲線條可在自然界中像是海螺、松果、花頭，甚至是我們所處的星系、銀河的基本形式中找到類似之處。對數螺線的概念對岩楔裝置是一大福音，無論活動岩楔收縮程度多大，凸輪與岩壁的接觸角度始終不便。改變凸輪的轉動角度可以同時改變岩楔的運用寬度以及調整受力角度。寬度調整以及受力角度之間具有互成反比的關係，增加岩楔受力角度意味著增加其適用的寬度，但同時也在凸輪承受攀登者重量的狀況下，減少其施加在裂隙表面上的承載力。這意味著岩楔製造商必須在適用寬度以及承載力之間取得平衡點。

2 These days, climbers tend to use the word “cam” to refer to SLCDs, but, technically, a cam is any tool that can transform linear motion (like a fall) into rotary motion (the rotation of a piece of pro to wedge it more firmly into place). That means hexes placed in a particular orientation, Tri-Cams, and even Big Bros qualify as cams, even though they have no springs.

2. 近來攀登者習慣以「活動岩楔」（cam）來代稱SLCDs，但就技術層面來說，岩楔泛指任何可以將線性動作（墜落）轉換成旋轉動作（藉由轉動單片凸輪將岩楔擠至定位）的器材。這就跟hex（六角岩楔）、Tri-cams（雞嘴巴）或是Big Bros（管塞）等器材放定位的功能一樣，只是前列器具並不使用彈簧。

3 It’s not completely clear who first developed the idea of applying a curved camming surface—modeled on a logarithmic spiral—to climbing protection. Russian climber Vitaly Abalakov invented a piece of gear that looks very similar to today’s Tri-Cams. At about the same time, Greg Lowe was working on a similar piece of climbing equipment in the States. In 1972, Lowe introduced the Cam Nut, a spring-loaded device with a single lobe and a single stem. In Lowe’s 1973 patent, he clearly articulated the idea of creating a curved device to create a constant camming angle. Lowe’s wobbly Cam Nut— which sold for $3.95—and its successor, the twin-stemmed, two-lobed Split Cam, were never commercial successes.

3. 究竟是誰先發展出將對數螺線概念與曲面凸輪結合、運用在攀登確保之上有諸多爭議。俄國攀登者Vitaly Abalakov曾發明過跟現今Tri-Cams外觀相近的器材。大約在同個時期，美國攀登者Greg Lowe致力於開發類似的器具。1972年Lowe將Cam Nut–一種單凸輪單軸的彈簧裝置–展現在世人眼前。在1973年的專利書中，Lowe聲明運用曲面裝置來維持受力角度的概念。然而，Lowe的設計不但結構鬆散且售價不菲（單價3.95美元），Cam Nut與其具有雙凸輪雙軸的次代產品Split Cam皆未能在市場得到正面回響。

4 The inventor of the modern SLCD was Ray Jardine, who was inspired by the constant-camming-angle concept in Lowe’s Cam Nut. Jardine, an aerospace engineer by training, had already been tinkering with new climbing gear for a couple of years when he first got a look at the Cam Nut in 1973. By spring of the following year, Jardine’s prototypes—which would later become Friends—were ready for a trip to Yosemite Valley, where Jardine used them to dispatch a slew of diffi cult-to-protect climbs. Jardine, who later became a pioneer of ultra-light backpacking techniques and equipment, used his SLCDs to put up one of the world’s first 5.13s, The Phoenix (5.13a) in Yosemite Valley, in 1977.

4.現代SLCD的發明者是Ray Jardine，他受到Lowe設計之Cam Nut所運用的維持受力角度的概念啟發。身為受過專業航太科學訓練的Jardine在1973年Cam Nut問事前幾年就已經著手設計新式攀岩器材好一陣子。1974年春，Jardine的設計原型（Friends的前身）被運用在優勝美地峽谷的攀登中，Jardine將這些器材運用在許多條難以架設保護點的路線上。除了身為超輕量化背包設計的先驅外，Jardine利用他所設計的SLCD於1977年在優勝美地峽谷裡完成史上第一條5.13級別的路線：The Phoenix (5.13a)。

5 Early on, Jardine kept his arsenal of new camming devices cloaked in secrecy. Fearing that his game-changing idea would be ripped off, he swore his climbing partners to silence. And the name that his camming devices ultimately would take was born from Jardine’s secrecy. He was known to carry his prototype cams in a blue nylon bag so no one could get a look at them. One day, when Jardine was preparing to go climbing, his partner, Kris Walker, wanted to know if the blue bag of goodies would be coming with them for the day. But since other climbers were around, Walker coyly asked Jardine if he had brought the “friends” with him. The name stuck.

5.在這之前，Jardine對新式岩楔的構想保密到家，並要求他的繩伴不要洩漏相關消息，深怕這扭轉運動攀登型態的構想會被剽竊，而Jardine的發明就是因為他保密到家的行徑而得名。當時他總是將他的器材原型放在一只藍色尼龍袋中，如此一來就沒人會看到。某一天，當Jardine正在準備攀登時，他的繩伴Kris Walker想問他是否會帶那袋藍色的好東西去攀岩，礙於當場還有其他攀登者，Walker只好輕聲問他是否有帶著「小朋友」來攀岩，於是「朋友」（Friends）的稱號不脛而走。

6 In 1977, a trusted friend of Jardine’s, Mark Vallance, started the gear company Wild Country in England to begin commercially manufacturing Friends. The first advertisement for Friends appeared in Mountain magazine in 1978. It called the devices “the revolution in climbing protection: vertical, horizontal, parallel-sided or even flared cracks—Friends work better and faster than any other device.”

6. 1977年，Jardine的好友Mark Vallance在英國成立Wild Country公司，並開始商業生產Friends。Friends的首支廣告出現於1978年的Mountain雜誌中。該廣告稱之為「攀岩確保革命：無論是垂直、水平、斜向平行，甚至外開的裂隙，Friends都比其他裝備更加安全、方便」。

7 Not everyone embraced the revolution. When Friends hit the market, some climbers denounced them as unethical, saying they made climbing too easy. Steve Levin, in Climbing No. 51 (1978), wondered whether Friends’ use should lower a climb’s technical grade, and whether it would be poor style to repeat a climb originally protected with chocks while using cams. In an interview forClimbing No. 170 (2008), the 1970s rock legend Henry Barber said he still didn’t use SLCDs. “I have cams, I’ve just never used them. They’re awesome, brilliant devices—fantastic technology. I’ve got nothing against them—I just never needed them.”

7. 並不是所有人都接納這項革新，當Friends進入市場時，有些攀登者拒斥其違反攀登精神、倫理，認為Friends使得攀登活動變得過於簡單。Steve Levin在1978年第51期的Climbing雜誌中探討使用Friends是否會降低攀登技術難度，或者利用活動岩楔重複攀登原本利用被動式岩楔（chocks）完成的路線是否沒有實際意義。在2008年第170期Climbing雜誌對1970年代傳奇攀岩者Henry Barber所做的專訪中，Barber提到他仍然不使用SLCD進行攀登。「我有買活動岩楔，只是從來不用而已。這是利用完美科技產生的極佳裝備，我並不排斥使用，我只是從來都不需要用到這些東西」。

8 The first SLCDs with flexible stems were created by Steve Byrne, who also cut the number of lobes on his design from four to three for narrower placements. In 1985, he began commercially producing his Three Cam Units, which had a flexible U-shaped stem, in Flagstaff, Arizona, under the company name Wired Bliss.

8. 首支有著彈性主軸的SLCDs由Steve Byrne做出，Byrne將凸輪數量從四片減少至三片，以應用在較窄的空間。Byrne從1985年起以Wired Bliss公司名義在亞利桑那州的Flagstaff，商業生產有著彈性U型主軸的三片凸輪組。

9 When Black Diamond’s Camalots first came on the scene in 1987, they added another new dimension to camming units: the double axle. The design, created by Tony Christianson, allowed the Camalot to get greater range without sacrificing holding power.

9. 當Black Diamond的Camalot在1987年問世時，BD在岩楔設計上做了突破：雙重轉軸。該構想由Tony Christianson提出，這使得Camalot可以在不減少承載力的狀況下有成更廣的適用角度。

10 Today, the largest SLCD a climber can buy is made by Valley Giant, which sells two sizes of cams: the VG9 and VG12 (nine- and 12-inch spans). They’re available by special request and cost $175 and $225. The smallest cam on the market is the Wild Country Zero, size one, which will protect a crack as small as 0.22 inches.

10. 時至今日，市面上可買到的最大尺寸SLCD是由Valley Giant公司生產，他們販售兩種尺寸：VG9跟VG12（分別有9、12英吋的寬度）。這兩款岩楔只接收特定訂單，售價分別為175、225美元。最小的岩楔則是由Wild Country生產的Zero(1號)，最小可以使用在0.22英吋寬的細縫裡。