EN 959 requires that subject products be supplied to the consumer with a data sheet by the manufacturer that details proper installation and technical performance information about the product. The responsible route developer will read this information thoroughly and understand the manufacturer’s specifications for properly installing the product and follow these recommendations.
The confusing nature of EN 959 however does not cover the actual bolt assembly itself. If in doubt, request a product information sheet with installation instructions from the manufacturer to understand the manufacturer’s performance specifications.
- CE/UIAA/EN certified and/or compliant rock climbing anchor of minimum 12mm by 70mm manufactured by a reputable company with a history of manufacturing climbing life safety equipment. [UIAA 123 / EN 959]
- Made entirely of grade 316 stainless steels or “better” (HCR steels and titanium).
- Non-wedge bolt (aka through bolt, para-bolt) type.
- If using glue-in bolts that are not made of titanium, use a model that doesn’t require counter-sinking.
- Installed according to manufacturer’s specs (i.e. torque properly set with torque wrench, proper glue type, proper sized hangers if applicable, etc)
- Matching materials end-t0-end (same alloy grade)
Minimum acceptable practices for schist
- Meet the following dimensions:
- 3/8″ x 3.5″ or 10mm x 85mm minimum
- > 3/8″ diameter: 5 times diameter in length
- Made of entirely 304 stainless steel
- If wedge bolt type with diameter of 3/8″ or 10mm, should be a double-wedge model
- Sleeve anchors should be 12mm or larger diameter and properly torqued with a torque wrench
Based upon conversations with Bolt Products, mixing 304 and 316 stainless steels is an acceptable practice as long as the two pieces have an exterior point contact. This is contrary to manufacturer recommendations and best practice would be to match alloy grades end-to-end as noted in “Best Practices”. Do not mix 300 series stainless steels with any other types of metals.
The UIAA has recently (Nov. 2015) issued preliminary findings that 304 stainless steel is no longer recommended for general use. Instead grade 316L (previously thought of as “marine grade”) should be used unless the area has shown aggressive corrosion conditions. Best practice would be to comply with these recommendations and use at least 316 stainless steel. This presents some problems, as grade 316 bolts are not readily available in the US at this time. The best grade 316 options readily available to the US market are as follows.
- Bolt Products offers bolts in grade 316 (A4 stainless in European terms) – http://www.bolt-products.com
- The Wave Bolt available from Climb Tech is 316 – http://www.climbtechgear.com
The next option would be various grades of high corrosion resistant steel or titanium which would provide the longest expected service life. Titan Climbing is the sole manufacturer of titanium gear, due greatly to the efforts of those involved in the Thaitanium project. HCR steel versions of bolts are in development.
Apr. 2016: The Access Fund has petitioned the UIAA to add exceptions to the proposed material standards that would allow 304 if the bolt is removable/replaceable.
Jun. 2016: Fixe and Petzl will both be offering new high corrosion resistant versions (aka HCR) that will be available at least in European markets “soon”.
Sept. 2016: Indeed Petzl’s HCR Coeur bolt (grade 904 stainless steel) is available at a exorbitant $40 for the hanger and bolt. Fixe is promising a more costly alternative with their PLX line of hardware, but we are unsure what alloy of metal they are using at the moment.
Sept. 2017: Maybe options exist for increased corrosion resistance at the moment. Debate still continues as to whether these materials are comparable to titanium in areas susceptible to stress corrosion cracking. In these areas, titanium is likely to best option as it has at least a minimal installation service life with good results.
While many climbers may spend a great deal of time thinking about the protection bolt placements of a route, cleaning the route, or ensuring the best line is selected, all too often the anchor is neglected and done on the cheap. The reality is that a proper anchor costs somewhere near $50 if using the proper materials and the expected norms of American climbers.
- A rap ring at the rope-bearing point of a rap-station anchor is a best practice, especially if the route receives or is likely to receive a high volume of traffic. A ring is free to rotate when the rope is pulled thus limiting repetitive wear at the same point as will happen in a chain link or similar connecting link. If an easy lower off configuration is desired a pig tail or pair of pig tails (aka rams horns) can be used.
- An even number of links off a standard hanger orient the rope such that it is parallel to the wall thus limiting kinking of the rope. An odd number of links can kink the rope when it is pulled.
- Orient any quick links such that the barrel screws down. This helps prevent the quick link from unscrewing as it goes through load/unload cycles and associated vibrations.
- Quick links need tightening, but not much. Somewhere between a 1/4-1/2 turn past finger tight with a wrench is approximately appropriate. Just finger tight or over-tightening with a wrench can make the quick link weaker.
- Choose a configuration that makes replacing the rope bearing element(s) easy. Shackles and quick-links are helpful here. It’s not ideal to require a future climber to jump through hoops when replacing your original components once they reach the end of their service life.
- An odd number of links off the hanger that lie parallel to the wall cause the rope to kink when it is pulled. I see this setup all too often as it’s the cheapest way to build an anchor when low-quality plated steel hardware store links are used.
- If vertically offsetting bolt placements avoid horizontal distances beyond 8″. Larger horizontal spacing between vertically offset bolts defeats the benefits of off-set bolts or will require a large amount of hardware to configure in a V-configuration. Consider something like the French style anchor or an inline chainset.
The so-called French style anchor configuration is rarely seen here in the US, though can be found occasionally in Québec. The largest benefit of this configuration is the lowest price of components and the lowest chance of kinking a rope. Most Americans would take exception to this anchor’s lack of adherence to the equalized / no-extension principals. European pragmatism considers the reality that a bolt failure is extremely rare and rope kinking is more common. The redundant bolts protect against an unlikely bolt failure but reduces the hardware required. The vertical offset nature of the French style also gives the largest number of options for positioning the anchor which is a benefit for lower quality rock types.
The in-line chainset configuration offers greater placement positioning than the American V setup and reduces hardware requirements. However, due to the nature of the bolts being joined by a chainset the placement possibilities are not quite as wide-ranging as the French setup. Many commercially available inline configurations rely on one single rap-ring which gives American climbers a general unease. It should be noted that even an un-welded 10mm rap ring would suffice in holding forces expected in a rappel. Even a sloppy weld would likely meet 25kn. With proper quality control it’s reasonable to expect a high quality 10mm link to meet or exceed 80kn. Europeans have settled on the reality that steel rap rings don’t fail and are not bothered by use of a single ring. This configuration is widely seen in Europe.
Perhaps the most familiar to American climbers. The v-set is created by two bolts oriented on the same horizontal plane. The simplest of this is the ring hanger or the quick link and rap ring pairing. More elaborate setups are built using chain. V-sets work best if the extension from the hangers is enough to allow the rap rings to touch when the rope is threaded into the anchor. This will limit the chance of the rope kinking.
A sub-set of a v-set, these aim to offer a cheap way to do all the right things but in reality end up being a compromise. While striving to orient the rope in the proper plane relative to the wall to limit the kinking, in real world use these can still kink the rope. Additionally, they don’t offer many clip-in points and when the ring needs to be replaced the entire hanger needs to be replaced which is problematic for 5-piece bolts.