Talk:Cable lacing

Removed bulk of recent addition on alternate ways to finish a "spot tie"
The following text was added in good faith by :


 * Spot Ties Spot ties start with a clove hitch used to lash the bundle together. This clove hitch then needs to be secured from loosening. A reef knot can be added to do this. A reef knot is essentialy two granny knots one-atop-the-other. A granny knot can break the lacing tape: the bending radius is too small. It is better to use a surgeon's knot. A granny knot is once-around while a surgeon's knot is twice around. Best is to use two surgeon's knots one-atop-the-other so that the lacing tape does not break so easily when pulled tight. A granny can be added on top of this at less tension to lock the entire assembly in extreme vibration environments.

This was intended to be referenced by this NASA requirements document. Other than an indication that the surgeon's knot is an acceptable substitute, none of the other claims (when to use the surgeon's variant, bending radius, prevention of lacing tape breakage, etc.) are supported by it. I reworked the text using corrected/standard terminology and contacted the author seeking additional support for these claims. While they don't seem entirely unreasonable, without any response supporting these claims I have removed the bulk of this new material. I did add an indication that the surgeon's knot is an acceptable alternative and referenced it with the supplied link. The actual text removed from the article was:


 * Spot ties start with a clove hitch to secure the bundle together. This clove hitch is prevented from loosening by the addition of a reef knot. A reef knot is essentially two overhand knots knots of different handedness, one atop the other. However the overhand knot can break the lacing tape, as the bending radius is too small. In its place a double overhand knot can be used, forming a surgeon's knot instead of a reef knot. Two consecutive double overhand knots, another style of surgeon's knot, can also be used so that the lacing tape does not break so easily when pulled tight. An additional overhand knot can be added on top of this, at less tension, to lock the entire assembly in extreme vibration environments.

--Dfred (talk) 02:46, 9 September 2012 (UTC)

Hello Dfred:

No, I don't have referenced information yet. I was taught by "Mae" in 1972. She worked in aerospace. She told of the two surgeon's, offered the granny finish, and warned of the granny breaking the lacing tape. I've tied countless spot ties. Yes, the granny makes it much easier to break the tape when pulling the knot tight. Also, the granny will tighten on its own and lock the knot early, while the surgeon's allows the tape to flow through it and tighten the underlying hitch further. Waxed tape flows much nicer than un-waxed. The two surgeon's knots can wind-up one above another. If care is taken, the second surgeon's can be landed next to the first forming a tight square-looking "buckle". This looks much better and does not loosen as easily when rubbed vigorously with a finger-tip. The tape should be cut at least 1/4 inch away from the finished knot because the tape still moves a bit and might draw a very short end in and release the knot. If the tape is cut with a blade, the ends will un-weave/un-ravel. If the tape is cut with a hot iron, this won't happen. There is a knot on the rover Curiosity that is just a hitch finished with one granny with very short ends. This knot has already loosened. I looked at that and the other knots and realized they had forgotten how to do it. (I had a student who interned at JPL and wound-up mounting a PMT (photomultiplyer) housing directly to a cryostat... the mystery was why it went through gallons of LN2 in a day... they had forgotten how that is done.) Mae showed me that such a knot would loosen immediately if rubbed with a finger. She also told me how she got in trouble because she would pull the knots tight using enough tape to grab ahold of properly to do the task: about 8 inches... and then cut this long piece and the roll away from the work, wasting 8" of tape. "Well, you go ahead and do it that way, and don't let 'em take your smile." The tape will sink nicely through your flesh when pulling the knots tight.

A problem with references is that the old knowledge will be lost. A lot of this isn't written down anywhere. A problem without references is that there is so much mis-information out there. Oh well.

John Ross — Preceding unsigned comment added by 76.94.213.135 (talk) 09:33, 13 September 2012 (UTC)

External links modified
Hello fellow Wikipedians,

I have just added archive links to 1 one external link on Cable lacing. Please take a moment to review my edit. If necessary, add after the link to keep me from modifying it. Alternatively, you can add to keep me off the page altogether. I made the following changes:
 * Added archive https://web.archive.org/20071201164010/http://www.gudebrod.com:80/electronic/Braid_Lacing_Tape.htm to http://www.gudebrod.com/electronic/Braid_Lacing_Tape.htm

When you have finished reviewing my changes, please set the checked parameter below to true to let others know.

Cheers.—cyberbot II  Talk to my owner :Online 11:15, 22 February 2016 (UTC)


 * Sunmist3 (talk) 23:26, 6 July 2016 (UTC)