The physics of tow rope strength?

[227]

I was thinking about this and wonder if there is a way to figure it out. Lets say you have a 350 lb ski, plus a 200lb rider which is 550 lb total. But with the drag of the water what should the tow rope break strength be? 1000lb?

Just a though....

Dude your way over engineering this. Your figures would apply if you were dead lifting the ski and rider with a crane and then jerking them up and down. That’s not the case with towing though, you simply need a rope that’s strong enough to pull them across the water, not lift them. I just bought a new tow rope and I think it’s rated around 200lbs. Its the cotton/nylon stuff you get at the hard ware store. It works fine, we’ve used it twice already.

I’m also going to disagree with the majority who like a short tow rope. If you have to tow any kind of distance, short tow ropes suck. Our riding spot here in Oceanside is about 3-4 miles form the safety of the launch ramp. So when we sink a ski here in the surf (which happens quite often) then, with a short rope we would have to tow at idle speed for 30-45 minutes to get back to the ramp. With a 35’-40’ rope the ski being towed is way behind the “V” wake coming off the ski towing so we can tow on plane between 20-25mph with makes that long tow about 5 minutes.

 

[Tkmww]

Just throwing it out for discussion. I've used the nylon ski rope type and that lasted a long time. It just broke so using the braided rope which is pretty thick so wanted to get to something smaller. I have 300lb braided nylon that is my new one...we shall see how long that lasts.

 

[kraqus]

I’m also going to disagree with the majority who like a short tow rope. If you have to tow any kind of distance, short tow ropes suck. Our riding spot here in Oceanside is about 3-4 miles form the safety of the launch ramp. So when we sink a ski here in the surf (which happens quite often) then, with a short rope we would have to tow at idle speed for 30-45 minutes to get back to the ramp. With a 35’-40’ rope the ski being towed is way behind the “V” wake coming off the ski towing so we can tow on plane between 20-25mph with makes that long tow about 5 minutes.

Yep...I have to agree with you, short ropes SUCK for long distances.
The only reason I used my Limiting/towing rope is to get out of the danger zone.
In big surf you want to be able to hook and tow as fast as possible, and get to shore (not the dock)
Same with the estuary we ride on a weekly basis, there is a lot of traffic with Big yachts and Ferries.
If you brake down in the middle of the canal, after you jumped a wake, I have to be able to do the same.
There is no time to float in the Danger zone trying to untangle a rope and hook the skis.
Once out of the danger zone you can assess the stalling issue and if further towing is needed then you bring out the longer rope.


EDIT: I am also becoming sort of a "Towing Loop Nazi". If you are gonna ride in dangerous spots you better have a towing loop in front and in the back of your ski. "Hook and tow" is the name of the game.....


Benny

 

[Tkmww]

Agreed! Short rope for danger zone, long for distance. Sucks getting sprayed in the face when being towed on a short rope. I will jump on the tow loop nazi wagon with benny, if you ride in surf have them on your ski.

Also another little tip: have your skis perpendicular to the crashing waves. If you are parallel you run the risk of getting smashed between the skis or having the skis smash each other. Has happend to me before and doesn't feel good.

 

[Odd Duck]

Another tip is to stop and hook the rope on the back of the running ski AWAY from the broken ski. Then just do a "drive-by", slowing only long enough for the guy on the broken ski to slap that caribiner(sp) on his front tow loop and away you both go. Less smashing between that way.

My tow rope is worn at all times, anytime I'm on my ski and it's long enough to go around my waist/hips twice only. I have fairly large, mountain-climbing caribiners on the ends and swing them around to my back while riding. I'm also using climbing rope that's fairly substantial. When I got it (ordered on-line) I thought, wow, that's too thick, it'll be a pain, but it got a nick in it fairly early on and I can still use it, so in retrospect, I'm glad I "overengineered".

And I'm a tow loop nazi, too. You BETTER have them on your boat if you're the one always breaking!

 

[ger87410]

Excellent idea, Odd Duck!

Us lake peeps are spoiled, I guess.

 

[Tkmww]

Yep, that works great...when they have a front tow loop. Put them on people!!!

 

[Odd Duck]

If it's an IDIOT that doesn't have a front tow loop, then I drop off my rope and let them struggle with the surf while putting it on (feed a loop through the bow eye, then hook to carabiner) and ride around until they're ready. Then swoop in, hook up to my rear tow loop and away we go.

If they don't know how to do it, I stop parallel to them with some distance between, explain the whole thing, then drop off the rope, etc, etc.

 

[JetManiac]

Great discussion and ideas y'all

Just throwing it out for discussion. I've used the nylon ski rope type and that lasted a long time. It just broke so using the braided rope which is pretty thick so wanted to get to something smaller. I have 300lb braided nylon that is my new one...we shall see how long that lasts.

I agree that you don't necessarily need a super strong rope. However, any knots, fraying, sun-UV damage, etc. can significantly lower rope strength. Other 'rope choice' things to consider: Too thin of a diameter rope will get tangled easier and could choke easier?, also a bright color rope that stands out in the water definately helps.

Yep...I have to agree with you, short ropes SUCK for long distances.
The only reason I used my Limiting/towing rope is to get out of the danger zone.
In big surf you want to be able to hook and tow as fast as possible, and get to shore (not the dock)
Same with the estuary we ride on a weekly basis, there is a lot of traffic with Big yachts and Ferries.
If you brake down in the middle of the canal, after you jumped a wake, I have to be able to do the same.
There is no time to float in the Danger zone trying to untangle a rope and hook the skis.
Once out of the danger zone you can assess the stalling issue and if further towing is needed then you bring out the longer rope.


EDIT: I am also becoming sort of a "Towing Loop Nazi". If you are gonna ride in dangerous spots you better have a towing loop in front and in the back of your ski. "Hook and tow" is the name of the game.....


Benny

"Towing Loop Nazi" I like it. It always seems that the people who most need to be towed are the least prepared and ride the least reliable skis and possibly have the least clues in general.

Another tip is to stop and hook the rope on the back of the running ski AWAY from the broken ski. Then just do a "drive-by", slowing only long enough for the guy on the broken ski to slap that caribiner(sp) on his front tow loop and away you both go. Less smashing between that way.

My tow rope is worn at all times, anytime I'm on my ski and it's long enough to go around my waist/hips twice only. I have fairly large, mountain-climbing caribiners on the ends and swing them around to my back while riding. I'm also using climbing rope that's fairly substantial. When I got it (ordered on-line) I thought, wow, that's too thick, it'll be a pain, but it got a nick in it fairly early on and I can still use it, so in retrospect, I'm glad I "overengineered".

And I'm a tow loop nazi, too. You BETTER have them on your boat if you're the one always breaking!

'Drive-by' "Tow Loop Naxi" I love it.

T-shirt ideas?


I was asked to post some pics of the clips that I use:
all stainless with no pins to rust

 

[Tkmww]

Those are sweet due to the seperate loop at the bottom for the rope. Carabiners seem to get dropped in the water since they fall off the rope. Plus the clip without the jagged edges will keep it from getting caught on the rope. Perfect design IMO. How much are you selling them for?

 

[Idok]

chris I need a pair of those next time I see you....those are way better than the ones I have now..

a hook n go sholudnt laset more than 10 seconds.....I have seen tows at my local break with riders in the water for 3-4-5 minutes screwing around with bow eyes, long ropes, tow ropes locked in sealed containers.....


short rope around the waist, on and gone in 10 seconds......and no problems with running on plane either, I towed somone in sunday with my shorty rope attatched to a boat with NO tow loops..so I had to loop it thru which made it even shorter....

the rider I towed was his first time on a standup and he made it all the way back to the ramp on a supershort tow rope going as fast as I could keep the pump hooked up..


I like ducks idea....if you dont have loops: "here's my rope!"