The "FB" sling friction hitch
Thanks to my climber friend Gregg Galiardi for showing me this knot.
The classic prusik hitch has a few problems. It can be fiddly to tie and dress properly, especially if you’re wearing gloves or have cold fingers, and the grip on the rope is not very adjustable. Often a prusik seems to be either hard to move / too tight or sliding / too loose. Plus, there's the confusion with the actual term - “prusik” can be a noun, a verb, an adjective, and a surname - Karl Prusik, the Austrian inventor.
There are lots of other knots that attempt to improve on the prusik, and the FB hitch is one of them. It's credited to the Austrian climber Franz Bachmann (“FB”, get it?) Yes, the same guy who invented the Bachmann knot, he's pretty busy.
I've never seen the FB hitch mentioned in any climbing book, with the exception of Andy Kirkpatrick’s “Down” (pg. 97). Andy writes that if you have to tie a friction hitch with a dyneema sling, this is probably the best method.
An Instagram fan mentions that this hitch can work on the steel cable of a via ferrata. I have never tested this and I don't know if it's true so your mileage may vary. But hey, I thought I would mention it.
As with any kind of friction hitch, your success depends on lots of variables, like the diameter and material of your sling, the diameter and slipperiness of your rope, what kind of load you're putting on it, etc. Practice in a controlled environment with the gear you typically use before you rely on this in real life.
What's the difference between this and a Klemheist hitch?
They are very similar. The one advantage to the FB is that it can be easier to slide the hitch after it’s been loaded. If you need to ascend a rope, this is helpful, especially if you're using a skinny Dyneema sling. Of course this depends on material and diameter of the sling, diameter and slipperiness of your rope, your own weight, and a few other variables. Give it a try and see if it works for you.
The FB hitch solves a few of those pesky prusik issues.
The amount of friction can be adjusted. Three wraps might work on a pretty fat rope, or maybe try four if your rope is skinnier
It's made with a sewn sling, which is stronger and more secure than a loop of cord tied with a knot
The overhand knot makes a loop that stays open because of the stiff bar tack sewing. This means the knot is a bit easier to tie, and more importantly, makes it easier to loosen and slide after the load is released
Instead of carrying a designated prusik loop, which is really only good for one thing, you can use a 60 cm sling, which you probably already have with you anyway
Like the prusik, it holds a pull in both directions
If you have to make a friction hitch with a skinny Dyneema sling, this may be the best way to do it.
The main downside: you have a weighted overhand knot in a sling, which can be really hard to untie. Might want to deal with it at home when you have some needle nose pliers.
It’s easy to tie, here’s how.
Tie an overhand knot close to the the stitches. Make this loop as small as possible.
Wrap the rest of the sling three or four times on the rope.
Pass the other end of the sling down through the loop made by your overhand knot.
