cable lace diameter vs bundle diameter table?

[coppercone2]

for flat lace, is there a table to help you choose lace size vs diameter of the cable or hose you are binding?

I found some generic recommendations for round lace.

Is there a mil or nasa document?

[Stray Electron]

  I worked with lacing cord and lacing tape in both TelCo and in aerospace manufacturing and I've never seen a spec like that.  I would contact some of the manufacturers of cable lace and related products and ask them that question.

   FYI the main difference between lacing cord and lacing tape is the cord is round and lacing tape is flat like a ribbon and is not supposed to cut into cut into cables as much as the round cord. I'm not sure about the tape but cord is available in both waxed and unwaxed varieties. We always used the waxed variety (coated with bees wax) for tying cables in the TelCo central offices.  All of the tape that I've seen has been unwaxed and made of a synthetic material such as polyester.

  PS I have some rolls of lacing tape here and I just went and got one and it's marked "18DZ Black Polyester, Cage Code 82110, AA52081-C-3, 500 Yd 457M, Braided Lacing Tape, Gudebrod, Inc".   This came from Martin Marietta Corporation so it is what they used for Mil-Spec assemblies but it does not appear to have a Mil-Spec itself and the only spec seems to be the AA number. 

  The other end of the roll has some other markings but none of them are probably important but it does say "Gudebrod, Inc Pottsdam, Pa 19464" so you can look them up. 

  My first job in electronics was running cables in various telephone companies central offices. We then had to tie the cable bundles about every ten inches. We first tied around the bundle and then tied another band between every vertical row of cables and then more bands of lacing cord horizontally between every layer.  Repeat every 10 or so inches for an approximately 70 foot run plus a roughly 11 foot vertical drop on each end.  I did that for two entire summers while I was in high school. You can only imagine how many times I've used lacing cord!  I went through a 500 yard spool about every four days. 

[coppercone2]

I just wanted to pick some up. I only ever saw it in Hughes and lambda equipment and it looked rather thin. The deals on eBay are for stuff that is over a mm for nomex. I have a feeling 2-3 mm is too wide for small cable bundles (I.e several 20 awg wires)

I thought it might be good for securing frayed ceramic fiber braid near the screw terminals, but if I have to buy 500ft I wanted to get some other uses from it.

1mm seems like a reasonable size for inside of chassis (rack) work?

[SeanB]

Got a roll or two of the white waxed flat, used for avionics, and a roll of unwaxed nylon canvas thread, normally used to stitch canvas. Both have been used for lacing, and also for use as a canvas tent repair, and for assorted work where I needed a heavy duty thread, and whichever one was closer was used, and with a cheap set of sailmakers needles to lace them and sew with. You will find the waxed is useful in a lot of applications, not only for lacing, or for end bindings, though there you probably are better off using a self adhesive lined heatshrink, though it does work well for making ends on fabric sheathed cables, when combined with a little heat to make the wax flow into the braid.

[Stray Electron]

I just wanted to pick some up. I only ever saw it in Hughes and lambda equipment and it looked rather thin. The deals on eBay are for stuff that is over a mm for nomex. I have a feeling 2-3 mm is too wide for small cable bundles (I.e several 20 awg wires)

I thought it might be good for securing frayed ceramic fiber braid near the screw terminals, but if I have to buy 500ft I wanted to get some other uses from it.

1mm seems like a reasonable size for inside of chassis (rack) work?

  1mm wide or thick?  I don't think that 3mm wide is TOO wide but it might be more difficult to handle. I use lacing tape for all kinds of things, so don't worry about not having enough uses for it.

   Take a look at "Lacing Tape"  (include the quotes) on Ebay and then select "used" category.  I found over 90 items and many/most seem to be US produced, so you'll at least have a an idea of what are getting. You can buy a roll on Ebay for as little as  $20.  There is also a Gudebrod catalog on there and it should tell you a lot more about lacing cord/tape.

[Halcyon]

Noob question from an outsider with a passing interest (I don't actually have any need to lace cables at all), but why used waxed vs. unwaxed? What does the wax do that makes it desirable to use?

[jpanhalt]

I have both in flat versions.  The white is waxed and just has a part number on it  LC-143.  It is slightly narrower than the black I have.

The black is nylon and is not waxed with beeswax but has a synthetic polycrystalline(?) material that helps hold the knots.  Made by Dearborn wire, "Finish E Size 3."  The size may be in mm. MIL T-43435 B Type 1

See: https://www.wiremasters.com/catalog/products/harness-management-products/tapes/lacing-tape/aa-5208-m43435/a-a-52080-mil-t-43435-type-i-nylon

Every airplane I have worked on  (all manufactured pre-1976) had white, waxed tape about the same or slightly smaller than the black variety I have.

Waxed tape hold knots nicely.  The black also holds knots as it does have a coating, but it also slides more easily and is a little easier to get nice flat lacings.

There is a NASA STD-8739.4  (chapter 9) that applies:  https://s3vi.ndc.nasa.gov/ssri-kb/static/resources/nasa-std-8739.4a.pdf

EDIT:  The cut ends on the lacing without beeswax tend to fray more.

[Stray Electron]

I have both in flat versions.  The white is waxed and just has a part number on it  LC-143.  It is slightly narrower than the black I have.

The black is nylon and is not waxed with beeswax but has a synthetic polycrystalline(?) material that helps hold the knots.  Made by Dearborn wire, "Finish E Size 3."  The size may be in mm. MIL T-43435 B Type 1

See: https://www.wiremasters.com/catalog/products/harness-management-products/tapes/lacing-tape/aa-5208-m43435/a-a-52080-mil-t-43435-type-i-nylon

Every airplane I have worked on  (all manufactured pre-1976) had white, waxed tape about the same or slightly smaller than the black variety I have.

Waxed tape hold knots nicely.  The black also holds knots as it does have a coating, but it also slides more easily and is a little easier to get nice flat lacings.

There is a NASA STD-8739.4  (chapter 9) that applies:  https://s3vi.ndc.nasa.gov/ssri-kb/static/resources/nasa-std-8739.4a.pdf

EDIT:  The cut ends on the lacing without beeswax tend to fray more.

   Yes, some of the lacing tape on E-bay shows Mil-Spec numbers on the rolls but I haven't looked up any of the numbers, I'll leave that to the OP.

[coppercone2]

ugh, this high temp wire I have is actually fucking wool or something inside. its only 75C rated but it looks like I shaved a sheep. i was thinking of just totally wrapping the strands in high temperature lace.


seriously its like someone stuffed wool into a cable lol. You got paper, colored strings and wool in there for a heater cord.

last time I saw this is when a cat got into a cheap couch

maybe I just stuff nylon braid over it

[coppercone2]

ok so this got me thinking

there is meta and para aramid which is nomex/kevlar

What the hell is ortho aramid? I see it cryptically referenced. what are the properties of this lack luster material?

[jpanhalt]

Ortho, meta, and para have the usual meanings for how the aryl amides are linked.  The image shows both common versions.  PPTA para-aramid and PMTA is meta-aramid.  The "V"  marks the ortho-position between the two NH's or CO's.   As with all plastics, there are modifiers present in the resins. 

Ortho-linking leads to more steric hindrance.  From an aromatic resonance standpoint, ortho- and para-substituents are quite different from meta-substituents.  It is not surprising that para- and meta-aramids have different properties, and the ortho-version is apparently not a commercial product. 

Is this thread about aramid chemistry or cable lacing?

[coppercone2]

materials choice in cable lacing is important. it sounds like this got messed up for boeing on the starliner
https://www.scientificamerican.com/article/crewed-starliner-launch-delayed-by-flammable-tape-botched-parachutes/


Flammable tape covering wiring sounds awfully like lacing tape

[TimFox]

Noob question from an outsider with a passing interest (I don't actually have any need to lace cables at all), but why used waxed vs. unwaxed? What does the wax do that makes it desirable to use?

Waxed lacing is easier to tie, since it sticks to itself at each knot, and resists untying.

[coppercone2]

how about teflon and rubber coated lacing? and I even see things like nylon coated nomex. never heard of nylon coating before


I assume teflon is like wax but does not stick as much, for things that are kinda abrasive and don't slide well. Rubber? I am not sure on that. Nylon coating? not sure either.