The Book of Hangers
“The different ways to connect with your stud.”
The Bolting Bible
This is free resource by HowNOT2 and our way of contributing to the 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. We also believe that if you are going to spend time and money to bolt something, you should do it well.
This book is in a blog format. This page points to all 17 chapters, and the end of each chapter points to the next.
A downloadable PDF is available HERE.
What's a Hanger
A hanger is how you interface with a bolt. Unless you glued in a "P", every bolt needs a way to be attached to, typically with a carabiner. Standard hangers start as a flat oval-ish 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 or even your ropes if you want to run them directly into the hanger.
Materials
Fixe sells PS (plated steel) which is cheaper than SS (stainless steel) but then they rust and corrode if used outside, especially if the bolt is stainless. Don't mix metals! They are intended for indoor use (such as climbing gyms). I know paying less 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. PS is also magnetic, where SS is not.
DON'T USE PLATED STEEL
Stainless steel is the only kind of material 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 some benefits but are uncommon and only intended for anchors.
ROUND STOCK
Bent and welded round stock, generally 8mm, is formed into the same shape as a standard hanger, but with the benefit of generally having less 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 should fit in the hanger. A 10mm or larger hole for the bolt is required because bolts smaller than 10mm aren't strong enough for most anchors by today's standards. It also requires stainless if outside and at least 2.9mm thick 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 the stainless could be unreliable. We don't find off-brands are any cheaper, and if they are significantly cheaper, then it's a red flag. Homemade hangers are typically thick flat stock with two holes punched in them and often look like they were made on a farm. Most of the time they are not stainless...shocker! Just think about Leepers that were recalled because they would break under body weight because of nerdy metallurgic reasons. If you are installing hangers that thousands of people that you don't know will be trusting with their lives, please use quality products.
Strengths
How much (levered!) bolt is still in rock???
Chains on 5/8" Bolt Tests
These chain link bolts should only be used to pull shear (sideways) and should not be used to pull a bolt in tension (straight out) because it deforms the chains significantly even though it is at forces you wouldn’t get in a normal use. We do not know the strength of zinc plated chains after corrosion has begun.
Not every hanger you'll find in the wild is new or up to today's standards, we tested a bunch of old hangers in this EPISODE. Some were old, rusty, recalled, burnt, or speciality aid hangers and all broke between 17kN and 36kN.
Old hanger styles we've tested with a varied degree of corrosion.
Temporary vs Permanent
In theory you can remove a "permanent" hanger held on by a nut but there are specific temporary hangers for permanent bolts without hangers. These bolts could be compression bolts like button heads or carrots, wedge bolts with or without nuts on them, or sleeve bolts (usually small and rusty), but they all have a little space between the head and the rock for you to fit a temporary hanger. This is more common in bolt ladders for aid climbing (rather than for sport climbing), or if you are way in the back country and the bolt is rarely used.Rivet hangers can look like offset hangers and they just slip on and stay on as long as a carabiner is inside of them. There are also rivet hangers that are a loop of steel cable. These are all available on Skots Wall Gear. We tested Skot's rivets in this EPISODE. The loops were almost twice as strong as the butterfly rivets!
Buying Guide
DON’T BE CHEAP AND BUY PLATED STEEL HANGERS! THOSE ARE FOR INDOOR GYMS.All prices below are as of Sept 2024.
FLAT STOCK
ROUND STOCK
Vertical Evolution has a 316L SS hybrid ring anchor welded to flat stock for €5.99 at Canyon Zone.
Bolt-Products makes one from a 8mm 316SS (A4) welded rod for a 12mm bolt at a price of €5.20. Bolt Product's are rated for 45kN and we could NOT break them in tension at 42kN and in shear at 52kN as the bolt heads would snapped off first so they are bomber.
Bonier makes unique bent hangers called the DUPLA and PINGO , where it is bent up on both sides and shaped so that no sharp edges touch the rope. They only come in 304SS which is super good enough for most situations. We did break tests on them in this EPISODE and like them very much. They used to be difficult to buy as the company is in Brazil, but we now stock them at the HowNot2 Store!.
Bonier's Duplas Tested
More is NOT Better?
Holy moly! Why is this so big??? There is always a reason that something is the way it is. In this case, too many climbers in a popular area were using the tree and damaging it, and as obtrusive as this is, it does scream "hey, use this instead". Yes it's strong enough, no we don't have to test it to know that. But holistically, it makes clipping a carabiner to this obnoxious at the very least to weakening the full potential of the carabiner at the worse, because it's pulling too much on the gate side. Maybe a nice wood sign nailed to the tree might have been a better solution?
CMI
has an oversized hanger that is intended for aborists work like rope course but it's not
stronger because it's bigger. If you pull in shear, it puts all the force on one side of the
hanger making it break around 31kN (still super strong enough). Only when you pull in tension
with a large connector does it even achieve it's MBS of 44.4kN.
NOTE: We've had some standard
hangers break at 60kN. Their oversized hanger is good if a tree is growing around it but not for
the visual impact of our climbing areas.
What's Next?
Chapter #6 - The Book of Concrete Screws