The Bolting Bible
The Book of Anatomy
Welcome to our free course as our way of contributing to the bolting community. It's nice to understand what you are clipping and trusting with your life, even if you never plan on installing or removing bolts. Also, if someone is going to spend their time and money to bolt something, I assume, they probably want to do it as good as possible. Hopefully, the Bolting Bible gives you the tools you need to do a great job. Get it?
Our courses are A-Z content in blog format, glued together with an overarching blog we call a textbook. A blog format is easy to read, easy to update, and easy to translate. Be sure to begin at the TEXTBOOK and at the end of each episode we'll point you to the next.
What's a Hanger
A hanger is how you interface with a bolt. Unless you glue a "P" into the rock, every other bolt needs a way to clip carabiners to it or have a rope connected to it. Standard hangers start as a flat oval-ish shaped metal pancake that is stamped with a big hole you clip to and a small hole for the bolt and then folded 90 degrees. Some hangers are stock rod bent and welded into a similar shape as a standard one. The idea is to have a rounder surface for your carabiners and even your ropes if you want to run them directly into the hanger.
Materials
Hangers can come in steel or aluminum, though, aluminum hangers are rare and were made for lightweight temporary uses. They are not as strong as steel, can corrode, and it mixes metals because bolts are not made from aluminum, so you can get galvanic corrosion if left permanently installed. This photo shows the aluminum corroding while the bolt is also rusting.
Fixe sells PS (plated steel) which is cheaper than stainless but then they rust and corrode if used outside, and even quicker if the bolt is stainless, don't mix metals. They are intended for indoor use such as climbing gyms. I know paying $1.83 (PS) vs $4.95 (SS) per hanger is tempting, but don't do it! You can tell the difference between the two by color, PS is more shiny and SS is is more grey, in most cases. Also PS is magnetic and SS is not.
Stainless steel hangers are the only kind of materials that should be used for hangers since we should only be using stainless steel bolts. PLX hangers are phasing out with the new EN standards of 316L. All the major brands sell 316L stainless hangers, see the buying guide below. Titanium hangers are pointless since we don’t have titanium mechanical bolts.
Shapes
FLAT STOCK
Bent flat stock is generally 3mm thick and comes in the standard diagonal most often seen. Fixe and Petzl have dimples punched into them to prevent spinning which is nice but not essential. Bonier makes unique bent hangers called the DUPLA and PINGO, which are flat stock shaped so that no sharp edges touch the carabiner or rope.
Offset or horizontal hangers have a straight bend allowing permanent rings or quick links to be offset to the rock so a rope isn't being smashed up against the rock at an anchor. Don't pull them in tension as they lever the bolt. They have their benefits but are not common and intended to be used only at anchors.
ROUND STOCK
Bent and welded round stock is generally 8mm and is formed into the same shape as a standard hanger, but the benefit is that it generally has less of an impact as they don’t shine quite the same way as flat hangers. They are also kinder to carabiners, not that it's a huge issue, and you can run a rope directly into them. Welds add a level of risk as a point of failure or increase the risk of SCC (stress crack corrosion) in certain harsh environments, though it is unlikely. If an area has that risk, you'd be using Titanium glue ins anyways.
Chains are also a form of this but are not ideal as you have to add a stack of washer under the first chain, putting extra leverage on a bolt. These are usually selected because they are "cheaper" but they aren't if you get stainless chain and stainless washers. It's common to have chain as part of an anchor but please don't directly attach them to the bolt.
What happens if you put a rope in a sharp hanger???
Standards Vs Offbrands
EN 959:2018 is a European standard for the safety requirements and test methods for climbing anchors. It says the eye shall be wide enough to accommodate two "pins", one with a diameter of 15mm for the lower part and one with a diameter of 11mm for the upper part. So at least two carabiners can always fit in a hanger. A minimum of a 10mm hole for the bolt is because bolts smaller than 10mm aren't strong enough to be used in most anchors in today's standards. It also requires stainless if outside and that it is at least 2.9mm thick metal without sharp edges (a minimum of a 0.2mm bevel).
Off-brands are fairly obvious as they have almost no markings, and though they are simple chunks of metal with no moving parts, the quality of