Mast Climbing

Black Diamond Bosun's Chair Review

But it isn't


The Black Diamond Bosun's chair is a well made chair produced by a well knows supplier of equipment for climbing. It has a padded seat, is comfortable and adjustable. There is only one problem with it. It is not a Bosun's chair.

What is a Bosun's Chair?

The simple answer is that a Bosun's Chair is a chair used by a Bosun. So what is a Bosun? According to Wikipedia a Bosun "is responsible for the components of a ship's hull." And as this is a very old word, we are talking about sailing ships and the chair used to haul crew up the mast.

If not a Bosun's Chair, what is it?

According to the Black Diamond website it is a "A padded seat for long hanging belays". If you don't know what a belay is, or don't intend to use this for rock climbing, this may not be the chair for you. It is always used by someone who is supported by a climbing harness but may need to hang out for some number of hours and wants to be more comfortable, not have their legs go numb, and basically enjoy life more. In the context of rock climbing, one climber may belay another by holding the other end of the rope that will support the climber if he should fall. According to the reviews on the Black Diamond website, people also use it when they are drilling the rock in the clifs to install bolts used by climbers to secure their harnesses.

Why not use it for climbing a mast?

According to Black Diamond technical support this is not a life support chair. In other words, don't let your life depend on this chair. They purposely leave off any specifications on the strength of this chair because they don't want people using it for life support. But what if you will have a climbing harness on and just want to use it for comfort? Fair question and is why I bought one. The problem is that the attachment straps are very long so you will not be able to get close to the top of the mast. But what about the adjustment straps? Can't I shorten the straps so I can get closer to the top? Another fair question. The problem is that you will just take another layer of strength out of the system. The adjustment straps are there to allow someone to tie each strap to a different anchor on the rock face and adjust the chair for level. The main attachment straps will no longer be carying the load. One final question. What if I am going to be in a harness and accept the risk of this unrated chair. The problem there is that it is just too easy to fall out of this chair. In my test I was just constantly having to slide back on the chair as there are no straps to keep the climber from falling out of the chair going forward. There is a backrest, but no crotch straps.

Why I wrote this review

There is not a lot of information on this chair out there. I looked at the reviews on Amazon and it was clear that people were using this chair to climb their masts. I do not think that is safe particurally as I know almost nobody uses a harness as a backup. Even the $200 Harken Bosun's chair says you must use a harness as a backup but I haver did until I started doing my Unassisted Mast Climbs. I saw a need for more information on this chair and decided to write this article and create the video and maybe save someone's life.

So why did I but it?

First, I did not know it was unrated. I assumed there would be instructions and specifications like every other piece of climbing gear I have purchased. There was nothing. That is when I called Black Diamond technical support. They were very halpful in explaining that this was not for life support and they didn't want people to use it for that. My motivation was that I use a climbing harness and a bosunn's chair and find the bulk of the harness very difficult to deal with. It interfers with the chair which has lots of safety straps and a thick backrest. I either needed a simple chair to go with my complicated or a simple harness to go with my complicated chair. Ultimately I found a harness that I like a lot. It has no padding and only the most simple loops to attach a carabiner or two. The Black Diamond Bosun's chair is going back to REI.

Petzl Tour Harness

NOTE: The following link is an affiliate link. I earn a small commission if you follow the links and purchase products. It helps keep me posting so please use the links.

The Petzl Tour harness is awsome as a backup safety harness to a bosun's chair. It is also super easy to put on. You can put it on without taking your feet off the deck, something I find very difficult to do wtih my old harness.


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