Weaver's Knot

I always get the words mixed up, but I believe there is a modern proverb that goes something like; "Neccesity is the mother of invention."  Sounds good even if its not the right phrasing.  And I think more to the point is how true the sentiment is.  The other day I was warping a rather large project on my PVC loom, and somehow or other, about four of my warp threads ended up being a yard too short.  I could hazard a few guesses as to how it happened, but the how it happened at the time was not nearly as important as how in the world I was going to fix it.  My first impulse was to just cut my losses and make my warp a yard shorter than planned and cross my fingers I included enough warp waste in my calculations.  That seemed very risky, though.  Especially since I was planning a lot of weaving on this warp- it would be awful to get to the end and be just short of a complete project.  
Then, my husband pulled out his phone and did some internet magic. (He is really good at that.) As a sat, aimlessly staring at the problem, he asked;
"What's a weaver's knot?  It looks like it could help."  I love that man.

A weaver's knot is pretty much magic!  It solved my too-short-warp-thread problem with such ease, it was almost unreal.  And the beauty of this particular knot is that you add length to your thread and the knot simply gets tighter under tension.  You don't have to worry about it slipping about or coming undone.  How awesome is that?  And I did complete the beast of a project I was working on, and the knots did their job without fuss.  I will say that the one consideration is the reed.  You want to be careful as the knots need to pass through your weave if the thread was a tight fit in the reed.  I had to manually push a few of them through, which took some time until I got past them.  But really, even though it added time to the weaving process, it saved me a ton of time from having a project that did not work out quite right. 

Here is how to make this wonderful knot:

1. In the thread that has come up short on you, make a standard slip knot.  Do not pull it tight yet.  You do not have to leave a long tail, the knot is suppose to be so strong you can clip the tails right off when you're done.  I left tails on mine and wove them in because I'm a scaredy cat.  In my example, the thread being lengthened is yellow.

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2.  Thread your new yarn through the loop of the slip knot.  Again, you should not have to leave a long tail as you thread the new yarn through the loop.  However, you can leave a tail long enough to weave in later if you're nervous (like me).  In my example, the new thread being used to extend the yarn length is blue.

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3.  With the new yarn threaded through the slip knot, pull the slip knot tight by pulling the two yellow thread ends.  Once it is secure, pull a little more.  You want the slip knot to pull your new thread through the twist of the knot.  I have shown both when the slip knot is pulled tight and then once the new thread as pulled through the knot.  I have found that the thread makes a satisfying little popping noise when it makes it through the knot.  This pull-through is what gives the weaver's knot its power, because as you pull, the knot now only tightens on itself.  In my example, you can see the little peak of blue looped through the yellow knot in the completed weaver's knot.

4. The knot is not complete.  The yellow portion of the thread is the yarn that needed to be lengthened.  The blue portion of the thread is the new extension to your yarn.  You will have a tail from the old thread and a tail from the new thread.