The Devil makes work for idle hands as the old saying goes. Probably enough Devil's work going on right now with this lockdown to save Robert Johnson.
You don't need to know a lot of knots or hitches, far better to know a select handful that you can learn properly. When I was climbing there were only really two or three that I'd use on a regular basis plus a couple that would be used infrequently.
While there are various gadgets such as Linelocs and the various weird and wonderful stuff from Dutchware, knowing a few knots and hitches can get you out of bother should you lose or break those items. Note that not all knots and hitches work on every kind of rope or line, some work better with "old fashioned" laid ropes whereas others will work with nylon kernmantel types, the hardest to work with tends to be dyneema as it's particularly slippery, you just have to find out by trial and error. As with every technique, practice makes perfect!
Basically the requirements of a knot or hitch are:
- It should be easy to tie.
- It shouldn't come undone when in use.
- It should be easy to untie when required.
There's no shortages of sites and videos showing how to tie these knots so do a search. I've linked to https://www.animatedknots.com for some of the knots, some of the names used on that site are slightly different to what many have grown up with but it should be obvious from the diagrams what is what.
There are two groups of knots/hitches in putting up a tarp: attachment and adjustment. There's also joining knots but they aren't as commonly required. Let's look at attachment first.
First up is the Bowline, the king of knots, https://www.animatedknots.com/bowline-knot probably one of the first real knots anyone is taught. It's easy to tie and is actually fail-safe in that regard as if you get the sequence wrong you don't even end up with a knot, the whole thing just falls apart. It's strong when tied, is easily undone even after being heavily loaded. Typical use would be to tie a line to a tarp.
The next two are very simple hitches: two half hitches and the slippery hitch. The half-hitch is what is often used by climbers to tie-off or "back up" the Bowline and other similar system critical knots. The slippery hitch is similar to the half hitch but rather than push the end of the line through the loop you push a bight of the line back through the loop. This is useful when you have a long length of line left and don't want to have to feed metres and metres of line through. Because it's a bight that's being used you've a free end of the line, if you pull on that then the hitch will unravel easily.
The final attachment knot is the Siberian Hitch https://www.animatedknots.com/siberian-hitch-knot . This is sort of a figure of eight knot with an inbuilt slippery hitch so it's easy to untie. It's a very easy knot to tie when your hands are cold and/or wet, sort of obvious given its name. You can also tie it whilst wearing mittens since it doesn't require great dexterity, again useful in the cold. It also undoes easily when required - just pull on the loose end.
One knot to avoid is the figure of eight on a bight - it might seem easy and convenient but it's a bugger to undo once it's been loaded. I used it when I started climbing - until I had my first leader fall and took about half an hour to undo it! I started using the Bowline after that. Its use is recommended at climbing walls because it's easy for the staff to visually check.
In climbers' terms these usually get called Prusik knots though only one is "a" Prusik knot https://www.animatedknots.com/prusik-knot (named after Karl Prusik). They are charactarised by their ability to slide when unloaded and lock in place when loaded.
First off is one that isn't a sliding knot: the Trucker's hitch. https://www.animatedknots.com/truckers- ... ck-release This is basically an in-line (sic) pulley. You'd typically use it at the second attachment point when stringing a tarp between two trees as an example. Create the Trucker's Hitch in the line, pass the line around the tree then back through the loop of the hitch - you've now got a pully. Pull the line taut and tie off with something like the slippery hitch.
While Prussik knots can be used a better way of adjusting lines is via either a Tautline Hitch or a Midshipman's Hitch, they are very similar and only really differ in the direction the initial loops go around the main line. Fairly easy to tie but once set can be left in place if you so wish. If left in place then you only have about 50% of the line length as adjustment until the hitch reaches the anchored end of the line.
This limited adjustment can be tackled in several ways. The simplest is to use a McArthy Hitch. It's not really anything special, more a way of routing the line. Take the line around the peg/stake and back to the anchor point on the tarp (best if you've used a Bowline for this), pass the line through the loop of the Bowline and tie off with a slippery hitch. Nice and simple but you need to undo it should you need to adjust the length/tautness of the line.
Next is a variation on the Taut Line Hitch: https://www.animatedknots.com/adjustabl ... hitch-knot (I think Benp1 showed this a while ago linking to Andrew Skurka's site) wrap the first couple of loops around the main line but then rather than forming the half-hitch further along the line make a loose loop around both parts of the line and pass a bight of the remaining line through it and then set the hitch. This basically forms the hitch at a suitable point for the current pitch. Depending on the length of your line it may be a little awkward passing all the remainder of the line round and round the standing line.
That last point is solved by the Farrimond Hitch. https://www.animatedknots.com/farrimond ... hitch-knot Having played around with this hitch it's basically a Prusik knot (the original style) with a slippery hitch to fix it. To tie it: pass the line around the peg/stake; make a loop in the free end of the line and place it over the standing part of the line such that the rest of the line passes back under the free end (there's only one way to make the loop where this happens); now pull the bight under the standing line and wrap it around it twice so you end up with a small loop sticking up between the standing and free lines; now push a bight of the free line back through this loop and set the hitch. The hitch can slid up or down the main line until tension is applied. To undo, simply pull on the free end and the whole thing will come undone.
If you want to be able to adjust the guy line from under your tarp then you need to run it out to the peg, around that, return to the loop on the tarp, through that and then fix the adjustable knot on the return line.
If you've to join two ropes or lines together then there's a class of knots/bends just for that. Which one you use depends on the relative diameters of the two lines, also some work better when tying to tape or webbing.
Double Fisherman's. https://www.animatedknots.com/double-fi ... -bend-knot Best for ropes of the same or very similar diameters. A very strong knot but almost impossible to untie once it's been loaded. Not too good for dyneema rope/line due to the slippery nature of that. Best avoided except for making permanent loops.
Reef Knot: AKA square knot. https://www.animatedknots.com/square-knot Simple to tie but can work loose with repeated slight loss of tension. For that reason leave long tails and/or backup with one half of a double fisherman's on either side.
Sheet Bend/Becket Hitch: https://www.animatedknots.com/sheet-bend-knot only really differ in the layout of the rope being tied into, called a Sheet Bend when the static part is an open bight, a Becket Hitch when it's a closed loop. Can be used to attach a line to tape or webbing and can be made "slippery". Useful.
If I was going to pick three to use then they'd be the Bowline, the Farrimond Hitch and the Sheet Bend/Beckett Hitch. The half hitch and slippery hitch often get used by default to back up other knots so you'd "learn" those just by repeated use. After those then the Trucker's Hitch should you need to properly tension things and the Siberian Hitch for really cold conditions.
Bowline: tying line to the tie-outs on a tarp, especially "permanent" ones.
Farrimond Hitch: any time I wanted an adjustable part of the system.
Sheet Bend: tying line to the tarp if you need to shift things around, for example if the current setup doesn't match your intended pitch.
There's no one right way of doing things: having your lines prefixed to the tarp means you can pitch quicker but if you need to adjust or move the lines to a different tie-out then you've got the faff of undoing and then retying the knot. Once you've settled on a few pitches it will become apparent which lines you can leave on the tarp and which are better left loose to fix as the situation requires. I've gone through pretty well all the options. I'm currently using some lines fixed to the tarp but with no adjustment loops and then use the Farrimond Hitch to form those. Some of the lines are permanent and use Bowlines, others move according to the pitch and are tied using a Beckett Hitch with a slippery knot finish.
Finally practice. Then practice more. I used the Bowline to tie into the rope when climbing, I used it for thirty years in situations where my life depended on it, I can tie it when blindfolded, behind my back, yada, yada. Probably the only knot I've tied more often is the one in my shoelaces.