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The Outside Cam Range
Which Cam for me?
There are a lot of cams out there. Knowing what each has to offer is essential if you are to find which is best for your purposes.
What are the different types of cam?
Broadly speaking there are two types of camming device. SLCDs (Sprung Loaded Camming Devices) and Non SLCDs.
SLCDs - these cams have to have their springs pulled back to insert the unit into the rock where, when the trigger is released, they expand. They make up 99% of cams that are used and are more popular than their Non SLCD competitors because they are very fast to place and can be placed one handed. For the purposes of this article we will be looking almost exclusively at SLCDs.
These camming units have the smallest range of any cams available but work in a unique way. A brass 'ball' is pulled back by a spring to be released to jam between itself, the rock, and the cams aluminium head. In the smaller sizes they are really for aid climbing but have been used where nothing else will go for free climbs. Beware, they are even more prone to 'walking' and being 'disturbed' than standard SLCDs.
Non SLCDs - these cams have to be placed more carefully (normally with two hands) and need to be given a tug to activate the camming unit. The Camp Tri Cam is the most popular Non SLCD cam. It can go into oval or fully circular placements (such as quarried shot holes), it can also be placed as a nut (passive protection) much more easily than a SLCD and bites through ice, scum and poor rock better making it popular for winter climbing.
What are the different types of stem?
Rigid - The original friends had rigid stems. This led to limitations in the smaller sizes in shallow and horizontal placements where the stem would be placed on an edge. This could lead the stem to deform (break). They also had massive potential to 'walk' due to there being no flexibility in the stem when clipped into the rope. Only in the 3.5 and number 4 Wild country sizes do they still have anything going for them. Here they are lighter than flexible friends, are stronger (in big sizes shallow placements cease to be a problem) and most importantly with big friend sizes - they are cheaper.
Cams 'walk' when they are placed in an even sided parallel crack. The movement of the rope causes the cam to move up and down or side to side resulting in the cam moving further into the crack - sometimes irretrievably. Cams have been know to disappear entirely into cracks or walk themselves in so tight that they become jammed. The solution is to extend them.
Flexible - Most cams now have flexible stems that can mould to the direction of pull making them much better than their older versions in horizontal or shallow placements. Keep an eye out for cams which have a flexible stem but no plastic support for it. These cams are normally at the budget end of the market and can be difficult to place or remove as when you pull back the trigger, the stem bends with it.
U Shaped Stems - These cams have a U shaped stem that joins to the outsides of the cam head like the The Metolius Power Cam. The result is a cam stem that is similar to the old rigid friends when loaded across the U frame but not when placed horizontally where they will bend easily. The U shaped cams fill a niche in the cam market because they have a couple of advantages over single stems and the old rigids. The trigger wire is protected by the U shaped stem (increasing trigger lifespan) and the units are often much lighter than their single stemmed competitors (important when you consider how many cams you often have to carry). In the case of DMM 4CU Cams they all also come fitted with an extendable sling as standard which is an excellent feature. Beware alpinists and Scottish winter climbers as cams with U shaped stems are often hard to operate with gloves.
What does using my cams 'passively' mean?
Black Diamond was the first company to promote 'passive ' strength of it's camming units due to the twin axle design of their Camalots. This meant that if you placed the cam in a tapering crack like you would a nut, then the cam wheels would not fold back on themselves if you took a fall. These days however this is less of a unique selling point as most cams have cam stops. Cam stops do the same job as twin axles and stop the cam wheels turning back on themselves if they are loaded passively. Though most climbers are unlikely to ever want to use a cam in this way as it is fairly unstable, it is good to know that in the event your cam does partially rip and then catch on something else, it won't just break.
Number of Cams/Head Width?
The number of Cams (or wheels or lobes as they are sometimes known) depends on the device. Most modern camming devices have four cams as this offers the best stability, surface area contact with the rock and adaptability to various shapes. There are however devices with three [Black Diamond C3s] two and one cam [Camp Tri Cams]. Less cams or smaller cams have the effect of reducing the width of the head of the device as do cams which are more tightly packed together (like the old Aliens). This means that they are more likely to fit into oval or even round placements or shallow cracks. They are also much lighter. All this is traded off against the fact that they have less metal in contact with the rock. If they are the only thing that will fit though, they are the only thing that will fit.
Can I repair my trigger cables when they break?
Trigger cables and triggers do unfortunately break from time to time. Cams receive a lot of abuse. If you are unlucky enough to have a cable snap on you whilst on a route then you can still probably place the cam with difficulty, but getting it out will be much harder as you will be unable to release the spring easily. Cams with double axles or U Cable stems seem not to suffer from snapped cables as much as other types of cam. This is because they stand up to repeated packing and unpacking better than cams where the cam lobes can rotate back on themselves or the trigger wires are unprotected. Many companies are reducing this problem by not using swage/wire triggers or using much smaller triggers. Metolius cams now feature kevlar cord instead of wire triggers - Metolius Master Cams. Hopefully in the future breaking triggers and cables will be a vastly reduced problem. The plastic part of triggers, the wire and the swage can all normally be repaired without sending the unit back to the manufacturer. Wild Country trigger repair kits are available from Outside. For other brands visit those companies websites to find the best way to repair triggers.
Caming Angle, Range, Weight - What's more important?
This is the great question that occupies so much pub and shop floor time. The information you need for the argument is as follows. The more range a cam has the lower its strength when placed will be. There must be a compromise between range and camming angle. The optimum camming angle is 13.75° as used by Ray Jardine when he made the very first 'Friends' in the 70's. As an example of the compromise stakes a Wild Country technical friends takes a 13.75° angle and light weight. Black Diamond Camalots take a lesser camming angle and weigh more but have a greater range. The question is therefore do you want fewer, heavier double axel cams or more, lighter single axel cams? You must remember that you can only place each cam unit once and a climb of a certain length will require a certain amount of cams, regardless of their range. Another thing to consider in the argument is that there's a better chance of a first time placement when a cam has a bigger range and if you are pumped and in a hurry that could be useful. There is more to this but we don’t have the space here. Argue amongst yourselves!
For a more in depth look at camming angles see this Technical Review By John Middendorf at bigwalls.net
How Important are the cams tapes/slings?
The sling or tape that is on your cam is more important than you think. It helps you identify each cam in a hurry by use of bright colours. It also helps reduce movement or the 'walking' of the cam. A great feature on cams is an extendable sling (DMM standard) as most cams have a very short sling and usually need extending on all but the straightest of routes. Most slings can be repaired by the manufacturer or by an approved company. Visit manufacturer websites to see the details (though for BD cams visit Yates Gear). There is a cut off for units older than 10 years so make sure you don’t send any for repair as the manufacturer will not be able to do anything with them.
How important is cam weight?
Cams are the heaviest bits of kit you'll use and you carry a lot of them. The biggest weight savings/differences can be found in the larger cams. Smaller cams often weigh about the same between manufacturers. Take into account the fact that cams with longer slings will not require you to carry as many quickdraws. It is also worth remembering that slightly heavier units will probably last longer.
What do you get when you pay more?
All cams sold in the UK have to pass the basic CE strength tests. Not only this but most cams on the market (certainly those sold at Outside) come from highly reputable manufacturers. When you pay more you do not get a cam that is less likely to break or fail. You get a cam which has better features and probably a longer lifespan. You pay more for extendable slings, plastic outers, double axels and other features that make the cam more usable. Budget cams are still perfectly safe without these features.
Image © Wild Country
