Paracord for tow loops?

[Steve P]

I was asked at tthe recent Cumberland event where I sourced the tough thin yellow tow loops I was using? While braided Mason’s twine from any hardware store works perfectly well, this product was microcord 1.18 mm parachute cord from Paracord Planet where I buy my tow lines.

So, FWIW, here tiz...

[mlachow]

Good source. I pick up other size paracord to use for F3b winch line sleeves.

[MarkRobbins]

any idea of breaking strength? i suspect it would be 100+lbs?

[Steve P]

It is one step below Paracord 95 which has a 95 lb tensile strength. Interestingly, they don't post a figure for the Micro Cord but my understanding is that it's in the 85-90lb range.

[Tom]

any idea of breaking strength? i suspect it would be 100+lbs?

At least......which kinda throws the whole “weak link” theory out the window......I’ll stick with braided winch line for loops.....

[Steve P]

Braided Mason Twine
18-gauge line with an approximate tensile strength of 155 pounds.

[MarkRobbins]

At least......which kinda throws the whole “weak link” theory out the window......I’ll stick with braided winch line for loops.....

yep, i've been using 50lb and 80lb test Dacron fishing line. It doesn't break...unless it does. But I am a proponent of: you protect what is yours. I put what I feel will protect my towplane on it and what is good for my glider on my glider... I feel it is a different answer from a 500CC tug to a 120CC tug and a Skylark vs a Ventus.

In fullscale we use a formula instead of feelings. but bones hurt more than feelings.

[Steve P]

"I put what I feel will protect my towplane on it and what is good for my glider on my glider... "

Question --- Do you also use a separate loop on the tow plane side? We easties have not been doing that? Just a loop in the end of actual 550 or 270 tow line. You ain't breaking that!

FWIW, I've always thought the "weak link" theory was in of itself weak. Seen lots of broken sailplanes on tow or bouncing along the ground when they caught a tip, but never a one saved by a loop?

Thanks

[Mosquito]

Hey Mark, will you have some of that Dacron this weekend? I would like to make a loop for my Bidule.

[MarkRobbins]

$1 per loop....or whiskey. Whiskey is good.

Why did I bring that up? I owe you Whiskey. I'll bring this whiskey this weekend and the loops are on me!

[edfmaniac]

I like 80lb Dacron with the glider end of the loop dipped in Elmers to stiffen it up, making it real easy to line up and load into the tow release. Dip it, massage it into the fibers and let hang to dry.

[MarkRobbins]

i wonder if that strengthens or weakens the original property of the material. Im going to try this...

[edfmaniac]

It never really hardens so I don't think it effects the strength of the fibers. Cheers!

[68mustang]

I have a few years of full scale tows and can say we only used the weak link at the glider end. To this day I don't really know which system is best but when we did long cross country tows to other contests etc., we never usd a weak link.

[mlachow]

If you use the micro cord, I recommend a double uni knot. Just search the web if you don't know what it is.

[Steve P]

The uni is certainly the best and how we repair high stress broken winch lines and such. What I've found at scale events is people making loops out of typical masons twine wherein the ends have become frayed right down to the knot. Then, the knot comes undone.

I've been using a simple double over knot for years, pulled super tight with zero failures and flying large heavy sailplanes. However, I melt the ends of the lines so there is no fraying.

Like most things YMMV.

[Steve P]

Tried to add a uni schematic to the above, but it wouldn't take. So, here it is....

[mlachow]

Interesting observation of micro cord vs braided twine for tow loops. If you have a tow release that has some sharp edges, the micro cord does a better job of dealing with your nasty tow release. Pulling hard, the twine will abrade and cut well before the micro cord.

If you are using the Topmodel tow releases you really should clean up the edges before installing them. That release normally has rough edges.