every 23:00:42 1999-03-10
2。SIMOND AND GRIVEL
ICE TOOL 小冰镐
-mh 09:57:01 1999-03-11
因为结构，使用技术和使用场合的不同，小冰镐，尤其是能换件的小冰镐英语里叫ICE TOOL而不是ICE AXE（冰镐）以示区别．鹤嘴尖（pick）有普通冰镐那样的下弧线形状的，也有上弧线形状（reversed curve)形状的．下弧线形的镐尖刃会在镐把向外抬起时咬紧冰，上弧线的在沿着镐把拉时咬紧（镐把外抬时放开）．所以下弧镐尖适用于登山时常见的六七十度以内较缓的冰雪面．以前提到的法式技术常用到这类冰镐．上弧镐尖适合用于难度高的垂直的冰面．这种镐尖是美国人Yvon Chouinard发明的，好象是Charlet Moser (CM)最早投产的．可以说这种镐尖给现代攀冰和登山带来一场革命．现在的ICE TOOL，尤其是攀瀑布冰或冰岩混合路径大都是上弧镐尖的．但这并不是必须的．爬接近垂直的陡冰的小冰镐多使用弯曲把以减少疲劳保护指关结．但这种弯曲镐把在进行雪上保护时不容易插到雪里，有使用局限．选择小冰镐的最重要的一点就是和手．CM, Grivel, Simond,camp,Kong,Lucky和美国的Black Diamon (BD), Lucky等都有不错的产品．不同人的手形，臂长，力量和经常攀登的冰的种类不同，对icetool的选择也不一样．好用的icetool有均衡的重量分配．头太轻了镐尖进冰不稳不深，容易敲裂冰面；太重了不容易精确下镐．有些卖icetool的商店挂有一块木牌让顾客试镐．注意试的时候带上厚手套．有些镐把很粗（BD的Black Prophet和一些CM的），手不大的人容易疲劳．天很冷的地区冰很脆，要用薄镐尖．由于美国有很多这样的地区，所以BD有不少又细又尖的镐尖和它的icetool配套．有些甚至薄到不符合ＣＥ标准以追求高性能．塑性强的夏天冰川冰对镐尖和冰爪的锋利程度要求不高．各厂家还用近花样提高镐把的减震性能．
独行马 11:09:09 1999-03-11
MH兄所提ICETOOR的优势主要表现在攀冰运动上，因为多以弯把、配重出现，锤头、铲头更换方便，但高山上仍然需用不同的两只冰镐，一是攀爬的原因，二是低温环境更换锤或铲极为困难，起码LEADER是如此。登高山人们仍常用传统的直把小镐，如CAMP的MICRO、和SIMOND（如岩石所用），因质轻便于携带、直把便于冰雪保护。但如果只为攀冰壁则实在不敢恭维。本人所用为韩国产TRANGO，弯把可换头（锤、铲和鹤嘴有配件），质量较轻，鹤嘴有倒勾，较易挂住自己。本届世界极限运动会上韩国运动员即用此镐获亚军。目前北京能见的小镐现货有：CAMP的MICRO 1和MICRO 2（直把锤头、铲头不可换）售价RMB980元，TRANGO系列（直把、弯把ICETOOR，售价RMB800－1000元）、AUSTRIA（ICETOOR铲头售价RMB1400元）。此三种最后一种价高没用过，不便妄言。具体视北东兄侧重点而定。
岩石 10 March 1999, at 6:23 p.m.
-mh 23:53:32 1999-04-08
很高兴能到损坏冰镐能得到调换．国外登山器材价钱贵是与优秀的售后服务分不开的．其实也不光是登山器材．．．另外文中说的"third tool"指的是攀冰时带的第三只小冰镐．Third tool主要在垂直冰上打保护点时用，或在主冰镐丢失后作应急．Third tool一般说来不如主冰镐做得结实，不适宜在攀登中替代“重型”主冰镐．ＣＡＭＰ的MICRO就是third tool．我在“见CAMP的网页 http://www.camp.it ...”一贴中问你们的冰镐是不是CAMP的MICRO 1 - MICRO 2小冰镐就是这个原因．如果只攀登短程大角度的冰雪时还是可以放心用的．
-mh 10:28:45 1999-03-11
独行马攀冰文章提到的冰锥旋入角度现在以有了新的看法．现代冰锥早与用锤子敲入的岩锥（piton）有了极大不同，设计现在都是管形有螺纹．顶尖咬入后用手或冰稿旋入冰里．但由于敲入式的旧式管形冰锥（ice piton）还能找到，为表明区别我这里直接叫icescrew（谁有现成的译名？螺丝？冰螺丝？:-），因为现代入流的厂商如Black Diamond(BD)，Grivel,Charlet Moser,Smily等的icescrew都是有深螺纹的．见
-mh 09:05:49 1999-03-12
独行马 10:28:26 1999-03-12
-mh 14:54:12 1999-03-12
王利发 22:33:19 6月20日
MYTHS, CAUTIONS AND TECHNIQUES OF ICE SCREW PLACEMENT
A Summary of Two Years of Research By Chris Harmston Black Diamond Equipment, Ltd.
Quality Assurance Manager, Materials Engineer BS, ME TURNING CONVENCIONAL WISDOM UPSIDE DOWN FOR YEARS MANUFACTURERS and "experts" have been telling ice climbers to place ice screws in certain ways, explaining that the holding strength will be improved in these situations. Over the last two years Black Diamond has diverted several hundred of its batch test samples towards investigating these placements and answering some fundamental questions. What length of screw is strongest? At what angle should the screw be placed? When should the screw be tied off? What is good ice?
HOW WAS THE RESEARCH DONE?
To investigate these issues Black Diamond designed and built special cells, or buckets, that allowed us to load ice screws in our Universal Test Machine using actual ice. These ice cells are made of 1.3 cm thick steel walls, 38 cm deep, with a surface area 33 cm high and 23 cm wide. They are prepared by filling with normal tap water and allowing to freeze at 10 +-5 degrees below zero centigrade. Freezing takes about 72 hours, during which time the ice expands, cracks, bulges, and overflows the cell. The top few inches of really bad ice is chopped off and a new layer of water is added and allowed to freeze. A screw is placed in one half of the cell and pulled to failure at 10 cm per minute. The screw generally fails by cratering the top 5-8 centimeters of ice away from the screw, bending of the screw and finally, either levering the hanger off the head of the screw, breaking the tube of the screw, or pulling the screw out of the ice. A second screw is placed in the other half of the cell near the first screw"s hole and similarly pulled of failure (yes, the ice is shattered and broken from the first test). After the tests are completed any broken-off screws are removed by chopping them out with an ice axe. The cell is placed back into the freezer and water is added to the old test holes and allowed to freeze onto the remaining ice. The cells are used repeatedly in this fashion up to 20 times before the entire cell is allowed to thaw and be "regenerated". As can be inferred, this technique of ice preparation is highly variable and unpredictable (not unlike real world ice), yet has yielded conclusive and supportable results.
The trends observed in Black Diamond"s static lab tests were similar to those recorded in static tests by REI Engineers in glacier ice and by Craig Luebben in Ouray and Boulder Canyon ice (see Climbing, Nov. ′97, p. 106). This suggest that the trends observed in laboratory ice are similar to the highly variable conditions and results found in the field.
WHAT LENGTH OF SCREW IS STRONGEST?
Intuition holds true in that long screws are stronger than short ones. However, the variation is relatively small for dense, solid, good ice. This conclusion does not hold true for "bad" ice- ice that is detached, cauliflowered, chandeliered, aerated, hollow, and/or slushy . Table 1 shows the number of samples, average, standard deviation, high, and low values obtained during routine batch testing that Black Diamond has conducted in ice during the last 2 years. All this data is from screws placed within 5 degrees of perpendicular to the ice surface. As can be seen from Table 1 there is a very large spread in the data, reflective of the fact not all ice is equal.
TABLE 1: Batch test strength results for Black Diamond ice screws placed in solid dense ice.
Does this data mean that you should always place the longest possible screw? Mostly, but not necessarily. There are several factors to consider. Assuming that the ice is thick enough for any screw, the placement should be strongest with the longest screw. How much surface ice did you have to remove to uncover good ice and how much good ice is left? How pumped are you while trying to place the screw? Is this the only piece of protection you are likely to get for some distance? How far out from the ground or belay are you? My recommendation is to place the length that makes you most comfortable in terms of protection level and pump factor. When you are close to the ground or belay you have the potential to generate more force on your protection. Make these placements as bomber as you possibly can. In other words, use longer screws when close to the belay or even equalize two placements if you are unsure of the quality of the ice.
Figure 1. Angle convention for testing ice screws.
AT WHAT ANGLE SHOULD YOU PLACE THE SCREW?
This question was investigated by placing screws to the hilt at various angles. Perpendicular is chosen as the reference and labeled zero degrees. The conventional "place the screw at a 10 to 15 degree angle against the direction of pull" is a negative angle. Placing the screw in the direction of loading is labeled a positive angle (see Figure 1).
As can be seen in Figure 2, there is a very dramatic change with the angle of placement. What we observed is that the direction of loading is significantly stronger. In fact, at 15 degrees from perpendicular the screws are over two times stronger when placed in the direction of load. The data included in Figure 2 is a compilation of all three lengths of Black Diamond ice screws using the highly variable test conditions described above. It is amazing that such a strong trend exists in such a variable experimental setup.
Figure 2. Failure load versus angle of placement. See Figure 1 for a definition of the placement angle.
SO, WHAT DO THESE PLACEMENT ANGLE RESULTS MEAN?
Should you place your screws 10 to 20 degrees in the direction of pull? The answer depend on several factors.
First, these results are only for Black Diamond Tubular Ice Screws. In other words, for these results to hold true the screw must have well spaced, external, high-relief threads that resist pullout. For pound-in protection you must always place them at an angle against the direction of loading in order to provide any level at holding strength.
Second, what is the ice quality? Is it detached, hollow, slushy, and/or rotten? If so, and this is the only option for protection, it may well be better to rely on the potential hooking/lever resistance ability of the screw rather than the holding power of the threads (an ice hook may be better in these conditions). If the ice is shaded, thick, dense, and "good" the placement will be stronger if placed in the direction of loading.
Third, if there is any possibility that the screw will melt out during the time you will need it to support a load, you should not angle it in the direction of the load regardless of the quality of the placement or of the ice. I have personally seen screws melt out so much that in the time it took lead and follow a pitch a screw at half height on the pitch could be removed without unscrewing. This occurred on Experts′ Choice Center W16 in Canada′s Waterton Park which was south facing (full sun), with the ambient temperatures below freezing. Due to the variables of ice condition, aspect, and temperature it is important to do what is needed for the specific route, conditions, and protection options you have at hand. Simply stating that all ice screws should be placed at one particular angle is not sound advice and could actually lead to failure of that protection. Every leader must carefully consider every placement and variable they can to optimize their protection system.
Figure 3. Effect of exposed leverage on the strength of a placement. The data points represent averages of tests conducted over several years with no record of what the angle placement was (approximately 10 samples per data point). The line represented by "Tie Off" is the average of four tie off tests (7-8 cm of leverage) that ranged from 2354 to 3299 lbf ( 10.5 - 14.7 kN). This suggests that if the screw sticks out more than 5 cm it should be tied off to increase the strength.
WHEN SHOULD YOU TIE OFF A SCREW THAT IS NOT PLACED TO THE HILT?
In the limited testing we have conducted with tie offs and various extensions clipped into the hanger, our data suggests that it is best to clip in directly to the hanger if the screw sticks out less than 5 cm. If the screw sticks out more than 5 centimeters, tie it off as you normally would. Figure 3 shows the effect of increased leverage on the screw versus strength. In the few tests conducted with tie offs the average strength is near 2700 lbf / 12 kN. The typical failure mode of tied off screws is that after about 1500 lbf / 6.7 kN the screw flexes and bends causing the sling to slip to the head of the head of the screw, resulting in high leverage. Failure is generally caused by the sling being cut by the edge of the hanger in the 2000 to 3500 lbf (8.9 to 15.6 kN) range. For the majority of placements this strength ranges is enough to hold typical falls. However, with a high impact force rope and a high fall factor, failure of the tie off could result. The best option is to simply place a screw of the appropiate length and not have to worry about tie offs altogether.
A word of caution relative to the tie off conclusions. This data is very limited. There is a very large variation in any given test setup. It is possible that the trends stated above lead us to the wrong conclusion. More testing is underway to verify these trends from a more controlled experimental setup and statistical analysis on a larger data set.
What is "good" ice? In our experience most ice is bad to varying degrees. Good ice is relatively difficult to find on modern vertical or overhanging routes. Good ice generally is found on lower angle slabs where the ice forms thick solid flows (blue, green, or clear ice). If the ice is hollow, layered, slushy, aerated (white appearance with obvious air pockets), chandeliered, cauliflowered, etc., screw strength should be suspect. What is the surface ice like? Does it dinnerplate easily? If so, you must clear this surface ice off. My experience has indicated that dinnerplate conditions occur most often right after or during rapid temperature changes and usually at colder temperatures. Does the ice have running water under or on it? If so, you may have to worry about the screw melting out due the water. In general, I have found that warmer ice shatters less and is usually capable of holding higher forces. From talking with climbers who have fallen, protection that held was more often in warmer conditions than in colder conditions and the protection that failed was almost always in cold brittle ice or horrible thin or slushy ice.
A final word of caution relative to equalizing two screws. Ice generally fails horizontally. Placing two screws horizontally also increase the force on the screws due to the triangle force multiplier (American Triangle). Place the screws vertically with one screw above the other. This will give the possible chance for both screws to hold.
Below are excerpts from a letter sent by Alex Lowe to Chris Harmston relative to the above information.
2 July, 1997
Good work on the screw research. Having read it and thought about the mechanics of pulls along the axis of the screw as opposed to loading such that shearing through the ice plays a role, it makes intuitive sense that a screw placed at a positive angle should indeed hold better, but only in ideal ice conditions - that"s the big qualifier. Of course, determining what constitutes "ideal ice conditions" is the art and essence of placing ice and gear. I felt you made this clear in your article.
My personal conclusion from your tests is to place screws at a positive angle when i feel the ice is `very solid`. Obviously some rather ill defined terms in that statement! `Very solid` will remain an intuitive assessment. But here are some attributes I associate with `solid` ice.
Appearance: Ice that is clear (glassy) in appearance usually contains less air, thus having grater density. Grayish, opaque ice is often shot through with air bubbles and thus is less dense and has less ability to support a screw placed at a positive angle. (At what declining density though does positive angle yield the advantage to zero or negative angle?) The effect your ice tools have had on appearance as you"ve climbed toward the screw placement is also informative. Pick holes will reveal brittleness, plating and layering and other indicators that affect my assessment of ice quality.
Sound: Low density ice often receives picks without creating much surface deformation. High density ice, because the dense ice must be displaced upon pick entry, often reveals a conical pit and other surface distortion where the pick enters. I would be more inclined to place screws at positive angle in the latter situation.
Torque required to turn screw: How hard is it to turn the screw once you"ve made your initial assessment and begun to twist it in? I don"t need the mechanical lever-arm advantage of the hanger to turn it in, I would not feel comfortable placing at positive angles. I would remove the screw and place at zero or negative angle.
Layering / consistency of force required to turn: As I run the screw I feel for consistency of resistance to turning. If I feel the screw break through into less dense layers I would remove and placed at a negative angle.
Again, these are general and intuitive indicators I use. In the end, there are absolutely no absolutes in assessing ice quality. I find this to be one of the appeals of ice climbing, wherein the art of the sport lies. Protection on a typical ice lead will still run the gambit of Spectres, tied off icicles, pins, positive-angled screws, negative-angled screws and most importantly, the confidence and experience to climb through unprotectable sections sans pro. Prudence, trust in gut feeling and experience are the requisite essentials for leading and protecting ice safely. The research you"ve done is great and becomes additional waeponry in my arsenal of criteria and options available in the back of my mind as I seek to make an ice lead as safe as I can. To apply the positive angle technique across the board would be folly but to add it one"s repertoire of savvy techniques adds certain advantage.
Alex was formerly the Quality Assurance Manager of Black Diamond. Some of the research reported here was from early work that Alex conducted while he worked for BD.
paul-l 20:56:31 6月26日
各位高手 现在BD的VEGA DOUBLE BOOTS不知道配合什么冰爪比较合适 卡式的/全捆绑式，易进的半捆绑式的。CHARLET S12 如何 高山药方面，国内可以买到的西药有哪些？
-mh 01:14:26 6月27日
北西南东 15:51:55 6月28日
-mh 00:17:19 6月29日
卡式的只要与靴子配合合适登垂直冰壁或雪坡上行军都可以．过去有很多人认为卡式容易托落．但那主要是因为靴爪配合没弄好．好的靴子前槽深，把新冰爪卡上去后，把前挡用锤子敲一阵直到前挡基本完全在靴子前槽里．冰爪在不系带是也应该能付在靴子上不拖落．卡式冰爪脱穿方便的确是一大优点，不但在混合地形,而且在手冻得不灵活和带子被冰封住时．另外卡式比捆绑式稍微轻些．卡式*一定*要与靴子适配好后再用．塞雪问题与冰爪齿设计和冰爪刚性关系密切．Charlet Moser,Black Diamond和 Grivel都生产防塞雪的冰爪底垫．我只用过CM的．不便宜但非常有效．（但听说Grivel的不太好用，底垫和鞋底间会塞雪）我建议所有要在雪上大量用冰爪的人使用底垫．塞雪不但沉重而且在下坡时有很大打滑的危险．有人说底垫在雪山上比同样重量的金子还值钱．
paul-l 07:48:01 6月29日
-mh 09:57:39 6月29日
-mh 07:24:53 7月05日
-mh 23:26:31 12月27日
bince 2000年一月20日 12:46 a.m.
冰镐应用坚硬的钢锉沿冰镐头两侧斜面慢慢锉尖,千万不能从上下边缘锉.这会降低稿尖强度.也不能动作太快,一定要一下一下方向一致的用力,否则会因为温度升高而造成镐尖退火.完成后冰镐除镐尖长度略有减短外外观应与新镐一样. 冰爪随种类不同略有差异,不过原则是一样的. 关键是整个过程一定要充满感情.
mh 2000年一月20日 3:09 a.m.
说句笑话，见谅! Mountaineering -- Freedom of the Hill (也叫"登山圣经")里讲了措法．避免镐尖退火很重要．
沙漠战士 2000年一月20日 10:07 a.m.
mh 2000年一月21日 5:08 a.m.