Towing a RIB and the results are in.. For now...

boatbum

Well-known member
Member
Joined
Mar 2, 2000
RO Number
36
Messages
6,660
Last Summer we had a couple of threads on the subject. Various means for towing a dink were discussed and this was all new to me and one other boater.

http://www.boatered.com/forum/topic.asp?TOPIC_ID=162346

http://www.boatered.com/forum/topic.asp?TOPIC_ID=161450

Having never formed an eye splice in anything before it was at the time a daunting task. The dink was new and cost about 20k. For me that would have been a huge loss.
Our itinerary was going to take us across Florida then to the Abacos. From there we were out in the Atlantic going to the Exumas. Finally we flipped around at Great Exuma for the return trip.
All in all this turned out to be about 1400 nm at a leisurely pace of about 8 knots. There were times when we hit 16k and things held together quite well.
We also had full day runs through genuine snot that had the dink slamming and our minds resolved to the notion we could lose it. But it all held together.
I thought I'd share what I wound up with and yes, it was all put together by myself.

There were three versions. First I used two 1/2 lines from Freedom out to the dink. I had some chafe gear but it was not enough. The lines frayed at the haws holes in the aft deck when we hit a foot of chop on Okeechobee. So we sat in Stuart while I rethought and rebuilt. I wound up with two 5/8 lines of the same material and extra chafe gear.
After arriving in the Abacos I had enough confidence in my splicing to convert to a bridle at each end with a hawser and that is composed of 5/8 3 strand to the hawser, and then another bridle at the dink. Soft eyes were used everywhere except where the hawser clips to the forward bridle and where the dink attaches.
These are what you see in the photo of the rig. The half inch lines were converted to a bridle for the dink.
Here is what it looks like in tow initially with both the 1/2 and then the 5/8 dual hawser. As you can see, you can try but the lines will never be the same length.

0424d8b9-7200-4234-b658-b5185a57a2cf_zps5abc776e.jpg


Moving on I wound up with the single line and here is a shot having made it through Cave Cay cut when the tide was running.

dada7f98-0c14-49eb-b40f-b4dadc87da2a_zpscf3c14c8.jpg


Here is the final rig;

afb38c9e-f6e8-416b-9441-4e9db77ceac6_zpse4ffea43.jpg


A couple of stainless spring clips make the connection to the dink. The splice instructions and several videos are available online or at Samson's website.
I will say with smaller diameter line using a fid size under what is recommended for pushing the ends through works much better. Just make all of the measurements with a ruler or tape.
 
Glad it all worked for you Dan.
I still like the dual lines for a safety measure and also to stop the tow from wandering.

The yellow braid with red stripe is a floater and strong. Glad to see you used it.
 
Yes it is good line. But it will slip through a cleat and it will abrade quickly. Even on a long leash at 8k the dink stays put behind us. I went with the two lines originally but after looking over the two 5/8 lines regularly I went to a single. We have a number of locks going across Okeechobee and many stops along the way. It goes much easier and faster with the single hawser and it is rated 7400 lbs with a minimum of 6300.
AB mentions using line that is at least 4x the weight of the tow. With the dink at 800 we are well covered and the heavier line is easier on the hands when pulling it in. And don't forget the gloves.
I wound up with a couple of good rope burns coming out of Emerald Bay in 2-3 following at 6 seconds. Deb was not happy about putting the boat in neutral for me.

I have to give a call to the Chafe Pro gear (black material over the 3 strand). It has velcro on the inside as well as the outside to grab the line and keep it from shifting along the line.
 
Dual lines are a PITA and the tender should not wander with a proper tow line and bridle setup.
 
quote:

Originally posted by Capt. Bill1

Dual lines are a PITA and the tender should not wander with a proper tow line and bridle setup.






+1, a proper bridle is the more efficient way. Plus it spreads the load out on the tie downs attached to the tender.
 
Gary the more I think about it, a single line is safer. At least for us. There's much less laying around on the aft deck when retrieving for a lock, and I don't have to worry about one line getting caught up in the dink outboard when I pull in the other. That is a very serious consideration and if you are not completely observant of where the lines are when you pull one in, you could be in for a heck of a mess if one line gets wrapped up in the dink somehow.
And that applies to releasing the dink when getting set for a long ride. I had to switch my effort between both cleats quite a bit to ensure the line being released did not go under the dink.
Now if you are talking about the likelihood of loosing the dink, that's a tough call. You could lose it because the dual hawser got all balled up as well IMHO.
I think after all of this experience a single hawser is safer in all regards. Particularly when retrieving, letting it out, or in rough water.
As always, YMMV.
 
Thanks for the feedback. As the poster of one of those threads I appreciate it. Looks like you have a very similar dink to mine which is an AB 4.7VST with a 50hp Yami outboard. I have only towed it once and it was in protected waters. My set-up is not as elaborate. I have the same tow line. I attach it directly to the trailer eye on the bow of the dink. If I were to tow in rough waters I would absolutely want to install dual tow eyes lower on the hull with backing plates. On the boat end I form a bridal out of a 3/4 dock line to a snap shackle that clips to the tow line. That way I can center the line on the stern of the big boat but adjust the length at will. I didn't do any splicing but just used boland knots to attach snap shackles as needed. I found that putting the engine skeg down into the water helped tracking an I had no trouble towing it for about 45min in protected waters. But I did find it cost me about 1.5knts off my normal cruising speed of about 22knts.
 
"But I did find it cost me about 1.5knts off my normal cruising speed of about 22knts."

That is very surprising and unexpected as a per cent of speed loss due to a towed inflatable. Our experience has not shown nearly that speed lost and I have no great ideas on why you are experiencing that % loss.
Perhaps it was the day you tested, or too short a tow line, or the short period of tests so far.
I am hoping that this is not the ultimate loss of speed for your situation.
 
I think the 4.7 is going to be the 15 foot version of the same dink. Ours is the 13 footer. I'm thinking over all you are about 150 lbs heavier and that line should be ok.
But I would put stopper knots on the bowlines. I found the line to be somewhat slick and unless it was wrapped on a cleat several times it pulls through.
 
Back
Top