Jump to content

Zip-ties?


Recommended Posts

OK, please try not to laugh: 

Are there any gotchas on what kind of zip-ties to use under the cowling and how to apply them? I went to take care of this a few days ago: 

 

and realized I didn't have any with me. 

On the one hand, not everything needs to be aviation-specific, but on the other hand I've elsewhere encountered 

  • brittle zip ties
  • zip ties sawing through things with motion
  • sharp ends causing later trouble

So maybe materials and design matter.
As for placement, my first thought was to take pictures and just apply them back in the same areas as before. 

Any thoughts appreciated. I figure it's better to over-noodle than to make assumptions.

D

Link to comment
Share on other sites

On 6/8/2024 at 12:10 PM, dkkim73 said:

OK, please try not to laugh: 

Are there any gotchas on what kind of zip-ties to use under the cowling and how to apply them? I went to take care of this a few days ago: 

 

and realized I didn't have any with me. 

On the one hand, not everything needs to be aviation-specific, but on the other hand I've elsewhere encountered 

  • brittle zip ties
  • zip ties sawing through things with motion
  • sharp ends causing later trouble

So maybe materials and design matter.
As for placement, my first thought was to take pictures and just apply them back in the same areas as before. 

Any thoughts appreciated. I figure it's better to over-noodle than to make assumptions.

D

Others will chime in on zip-ties, but for the hoses shown in the link it should have stainless steel hose clamps on those yellow  Tygon hoses. 

https://www.mooney.com/wp-content/uploads/2020/12/SBM20-319.pdf

  • Like 1
Link to comment
Share on other sites

Just in general on zip ties, get yourself a pair of flush cutters to cut the tag end off.  Regular diagonal cutters leave a very sharp end sticking out, I've been cut by a lot of them over the years.

These are cheap and work really well.   https://www.amazon.com/gp/product/B087P191LP

I have a pair that are only ever used on zip ties and other plastic.  I've found that if you use them on other stuff they deform a little and don't cut as flush anymore.

 

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

6 hours ago, LANCECASPER said:

It should have stainless steel hose clamps on those yellow  Tygon hoses. 

https://www.mooney.com/wp-content/uploads/2020/12/SBM20-319.pdf

The breather tube on my M20J is stiff and I asked Frank Crawford what it was made of and he looked it up and the drawing says poly vinyl. It would seem that Tygon might be a better choice on the older airplanes as well.

Link to comment
Share on other sites

Good, temp-rated, heat-stable zip ties are fine inside the cowl.

The problem is, not all zip ties are created equal and some will be terrible under the cowl, get brittle quickly, break, etc.

It used to be, in general, that black zip ties were generally the good high-temp ones, but I think that's not necessarily true any more.

Don't trust zip ties from Harbor Freight.

Zip ties made specifically for electrical contractors or high-temp applications are generally pretty good, but you still have to be careful what you get, as there's a wid variety of materials and quality.

I experimented with a good, contractor-style white zip tie to hold one of my scat tubes in place inside the cowling and it's been doing fine for about six years.   I gave it a tug today and it still seems great.   Unfortunately, it's been long enough that I don't remember where I got it or the pedigree or anything, but it is possible to get non-black zip-ties that hold up.

A bunch of black zip ties came with the last two ignition harnesses I purchased, and they've been fine.   No idea where they were sourced.

Cheap, generic zip-ties are generally no-bueno for high-temp stuff, or at least shouldn't be trusted.

And +1 that a good pair of "flush cut" pliers are great for cutting tails off zip ties and leaving a flush, non-sharp end.    There are some decent little ratchet tools, that look like a gun, to pull them tight and take the end off at reasonably optimal tension, and they do a good job of not leaving a sharp end, too.    They're not always great for getting into tight spaces, so generally the flush cutters are a better  go-to for not leaving sharp ends.

Basically, just pay attention to quality and temperature rating and you have a much better chance of getting something that'll last.   There are some nice newer technologies on the locks, too, that are pretty cool, and some end styles that make it easier to tie multiple bundles together, etc.    There are lots of options.

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

@PT20J @jetdriven      In the March 2015 revision of the M20TN Illustrated Parts Catalog Mooney specifies Tygon for that hose (page 79-10-00). Tygon is stronger and doesn't collapse as easily and handles heat better. It also specs a 5/8" x 7" spring inside of the Tygon near the air/oil separator. "(SPRING INTENT IS TO PREVENT COLLAPSING OF TYGON TUBING)".

  • Like 1
Link to comment
Share on other sites

4 hours ago, M20F said:

My plane would fall apart if not for zip ties. 

LOL, I think they all would...  I definitely would have a lot of wire lying on the floor of my cabin.

  • Like 1
Link to comment
Share on other sites

I really have a problem with zip ties, at Thrush we used a lot of them, and I saw many problems as aircraft aged.

I’ve seen many wires broken by zip ties, and I’ve seen engine mounts almost cut in two, a little oil and sand makes a zip tie a very effective cutting tool with movement.

There are a few places where zip ties are called for but for any wiring lacing cord is best, and under the cowling usually a DG clamp is better.

Lacing cord requires a little skill sort of like safety wire, and DG clamps do cost pennies more and take a little longer.

  • Like 2
Link to comment
Share on other sites

If you’re going to use zip ties, using high quality ones is worth the extra few cents they cost. I used to be the king of cheap zip ties but got tired of the damage the rough underside did to whatever they’re wrapped around. I’ve become a Thomas & Betts evangelist and now only use the original Ty-Raps. The smooth underside and stainless locking tongue make them a much better choice than the cheaper ones.

IMG_1050.png

  • Like 2
Link to comment
Share on other sites

Is the lacing a general replacement for places that people tend to use zip ties? And, for the original question, this would be under the cowl, so hoses and cables more so than wires, though both, really...
 

Link to comment
Share on other sites

1 hour ago, dkkim73 said:

Is the lacing a general replacement for places that people tend to use zip ties? And, for the original question, this would be under the cowl, so hoses and cables more so than wires

The classic approach prescribes lacing for electrical wiring and Adel clamps for hoses and cables.  That said, every mechanic I've ever spoken with about this says they use zip ties where reasonable.  "Reasonable" is up to their judgement, like so many other things.

  • Like 1
Link to comment
Share on other sites

2 hours ago, dkkim73 said:

Is the lacing a general replacement for places that people tend to use zip ties? And, for the original question, this would be under the cowl, so hoses and cables more so than wires, though both, really...
 

Lacing used to be (as in starting in WWII or earlier) the go-to way to keep wires bundled.   There are standard ways to tie the lacing, as described in AC 43.13.   I had to learn it in A&P school, and we had a test board where the DME could ask you to demonstrate lacing a bundle.   We'd walk by the test board all the time in school and you could see where somebody else had to chop out the old lacing and redo it as part of a practical exam.   I did when my turn in the barrel came and I think my lacing lasted about a week until the next guy came along, chopped off my lacing job, and ZIP-TIED it.  From then on it always got zip-tied.   I think I was the last guy in that school that had to demonstrate lacing.   Derp.

FWIW, zip-ties (i.e., Ty-Rap) were invented specifically for securing wire bundles in aircraft manufacturing in the late 1950s.

Link to comment
Share on other sites

3 hours ago, EricJ said:

Lacing used to be (as in starting in WWII or earlier) the go-to way to keep wires bundled.   There are standard ways to tie the lacing, as described in AC 43.13.   I had to learn it in A&P school, and we had a test board where the DME could ask you to demonstrate lacing a bundle.   We'd walk by the test board all the time in school and you could see where somebody else had to chop out the old lacing and redo it as part of a practical exam.   I did when my turn in the barrel came and I think my lacing lasted about a week until the next guy came along, chopped off my lacing job, and ZIP-TIED it.  From then on it always got zip-tied.   I think I was the last guy in that school that had to demonstrate lacing.   Derp.

FWIW, zip-ties (i.e., Ty-Rap) were invented specifically for securing wire bundles in aircraft manufacturing in the late 1950s.

Military at least AH-64’s we were prohibited from ty-wrapping wires. AH-64 had wire bundles as big as your wrist, and you don’t zip tie, ty wrap etc for the same reason you don’t solder wires if possible. You see both form a “hard joint” that is an inflexible spot where any movement results in the wire bending, bend it enough and it breaks.

A model Apache had Kapton wire and those familiar with it will understand why we were extra careful with wiring.

Lacing is flexible and does not present a hard inflexible joint that makes the wires bend.

There are lots of new ways that aren’t always better. On the Chain Gun but only on it the safety wire was some sort of prefabricated cable and you pulled this cable through and installed a swaged end on it as opposed to twisting wire. I think it was maybe being tested was why only on the gun. It was faster.

I think this is a link to it, and looking at prices I think maybe that’s why you don’t see it much

https://dmctools.com/products/safe-t-cable/tools-kits

Then we had “pre-load indicating washers” on pretty much the whole Rotor head and with them no torque wrench was used. They were slick, three pieces, a collar with holes in the middle of two regular washers, keep tightening until the collar was squashed flat and could no longer rotate, you used an awl in the holes to check rotation. I wouldn’t be surprised if they were $100 ea.

Zip-ties have their uses of course especially on temporary installs, but in my opinion if you lace wires years later you will have fewer problems.

Zip-ties are good to hold bundles until you get them laced for instance

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.