The Grass Bend looks to me to have its ends oriented the same as in ABOK 1406 as opposed to ABOK 1407. That is, ABOK 1490 looks just like 1406 tied using flat material to me. If using the same material, I do not see how 1406 would differ from 1490 in structure or mechanism. Granted, flat material or straps would behave somewhat differently. Not that this is authoritative as far as I know, but, this video of the tying of a grass bend is of the ABOK 1406 http://www.youtube.com/watch?v=-ElzdyZqfrc. -- DDK
You are right DDK. And once again we have another uninformed and misleading video from selfmadesailor. The knot shown in the video is tied using round cordage, and is therefor called the What Knot ABoK#1406. Only when tied in flat material, is it called the Grass Bend ABoK#1490. Same structure, round vs. flat material, different name. It's called the Grass Bend to reflect the shape of the material it is tied in. ABoK#1490 is also known as the Stop, or Strap Bend in some countries.
alpineer
Not to get technical nor to be disagreeable, but, I do believe that selfmadesailor is accurate on this video. That is to say that as the width of a strap becomes closer to its thickness, ABOK 1490 becomes the same as an ABOK 1406 in the same way a rectangle becomes a square. Technically speaking, calling a square (special case of) a rectangle (general) is completely accurate and is often done for good reason. ABOK 1406, therefore, is a Grass Bend, albeit, special case thereof. Sorry to split hairs, but, given your comment about the video and its producer I though it needed saying. As for selfmadesailor's other videos, I have not seen them nor can I comment on their accuracy. Sometimes even the blind ...
DDK
P.S. BTW, Not many parts of the ropes stay round in the final form of a tightened bend.
Edit: Actually, I think there is an additional very good reason to use the name Grass Bend for ABOK 1406 in that it helps to differentiate the two Whatknots. One Whatknot shows high levels of positive cogging, the Grief Knot, and the other does not, Grass Bend. I believe their difference in behavior may have been the reason that Ashley labelled these knots as being of theoretical interest.
@ DDK, I must agree totally with your post.
It is a sad reflection of the sloppy (or should I say organic) 'history' of knots that puts us in the position of having knots named by numerous aspects that have nothing to do with the form and function of those knots. Our history dictates that what a knot is tied in, how it is made, even what it is to be used for (or by what trade), will define its name. In hindsight, chemistry has a similar background - if I take Sodium metal and burn it is Chlorine gas, I make a white dust - If I take 'Spirits of salt' and mix it with soda ash, I get clear crystals - If I take 'Sea Brine' and evaporate it to dryness, I get 'Table Salt'.
It took the clear minded thinking of Chemistry to come to the understanding that these were simply three ways of making the same thing.
Personally, I find it quite exciting that today we are standing at the very junction between 'Knot Alchemy' and 'Knot Science' and 1406, 1407 and 1490 are exquisite examples to utilise in deminstrating this transition.
As we have discussed before, 'Cogging' is one of the fundamental elements of knot functionality and in this one delightful knot, 1407, we have probably the best example of a knot exhibiting as near 100% +ve cogging as we will ever witness. Then in 1406, by shifting the cogging to opposing rather than reinforcing, we have what we might consider to be 100% -ve cogging - i.e. possibly the perfect 'knot' with respect to this aspect of knot functionality.
Take some 10mm flexible braid, preferably with notable surface patterning, and make 1407. Then load the SP's gently and note that as the tension goes on, the SP's apply a rotational torsion to the opposing cord's collar at the same time as generating a linear frictional pull on the opposing cord's end. Both cords exhibit identical forces and flows, and nothing in this knot steps in to block any of these movements. Interestingly, the knot is symmetrical with respect to this flow - load the ends instead of the SP's, and the cord flows back through the knot the way it just came out.
Now make 1406 (1490) and load it - the collars are rotated as in 1407, but there the similarity ends, immediately, flow and rotation of the ends is opposed by frictional contact with the opposing flow and rotation of the other end. As cord flows out of the collars, the knot tightens creating greater lateral pressure on the adjacent ends, reinforcing the ability of each to block the flow and rotation of the other. 1406 / 1490 has a -ve cogging component that is reinforced with positive feed back as the knot is loaded. Of note, every knot I have studied that auto dresses itself without through feed of the ends, has a
positive feedback -ve cogging component at or near its ends...
It is a shame that Ashley called them both the Whatknot, because although the difference in topology is only tiny, the difference in functional structure is massive, and there is no way we should be countenancing calling them the same. As DDK suggests, we should be striking out 1406 and calling it 1490, and it really does not matter what material it is tied in.
Derek