Fixed capstan for launching

BogMonster · 31 March 2023, 11:50

I have a plan that I'd like to follow to modify my trailer for easier and quicker launching. I have a DeGraaff roller trailer which is really good but at the moment the launching process is to lower the boat on the winch, which takes some time and then needs the winch cable to be unhooked which comes with a distinct risk of getting wet on steeper beaches.

I have successfully experimented with unhitching the winch while the boat is fully on the trailer and lowering the boat using the bow line and a couple of turns around something as a brake. It has the benefit of not having to get out to unhook the winch rope as you can lower the boat controllably into the water and then flip the bow line off and over the rollers, let the boat drift away from the rollers and pull it back in to the beach alongside, it is a lot quicker and easier.

The issue is that the trailer doesn't really have anything that is good to use as a capstan for controlling the rope. I've used the jockey wheel body, but ideally a dedicated fitting of some sort that is a bit higher up and roughly in line with the bow eye would be better, as the rope tends to ride up the jockey wheel due to the angle, and sometimes jams near the top.

So I want a fixed capstan-type fitting that I can bolt to the trailer or winch post, but I've not seen anything like this. What I want is to find something that looks similar to the capstan in the attached (just an unrelated photo off Google) which can take a couple of turns of the 10mm bow line rope to allow controlled paying-out.

Has anybody done a similar thing? Any pointers to something I could fit or modify please?It doesn't need to be big, enough to wrap two or three turns of 10mm rope around. The 48mm jockey wheel body works, but it could be a bit fatter than that for more grip, maybe 75mm or so.

beamishken · 31 March 2023, 12:51

Quote:

Originally Posted by BogMonster

I have a plan that I'd like to follow to modify my trailer for easier and quicker launching. I have a DeGraaff roller trailer which is really good but at the moment the launching process is to lower the boat on the winch, which takes some time and then needs the winch cable to be unhooked which comes with a distinct risk of getting wet on steeper beaches.

I have successfully experimented with unhitching the winch while the boat is fully on the trailer and lowering the boat using the bow line and a couple of turns around something as a brake. It has the benefit of not having to get out to unhook the winch rope as you can lower the boat controllably into the water and then flip the bow line off and over the rollers, let the boat drift away from the rollers and pull it back in to the beach alongside, it is a lot quicker and easier.

The issue is that the trailer doesn't really have anything that is good to use as a capstan for controlling the rope. I've used the jockey wheel body, but ideally a dedicated fitting of some sort that is a bit higher up and roughly in line with the bow eye would be better, as the rope tends to ride up the jockey wheel due to the angle, and sometimes jams near the top.

So I want a fixed capstan-type fitting that I can bolt to the trailer or winch post, but I've not seen anything like this. What I want is to find something that looks similar to the capstan in the attached (just an unrelated photo off Google) which can take a couple of turns of the 10mm bow line rope to allow controlled paying-out.

Has anybody done a similar thing? Any pointers to something I could fit or modify please?It doesn't need to be big, enough to wrap two or three turns of 10mm rope around. The 48mm jockey wheel body works, but it could be a bit fatter than that for more grip, maybe 75mm or so.

Why do you need to slowly lower the boat? I just unhook the winch then let the boat go on a slack line then pull it in once its afloat once it hits the water it slows anyway so usually only goes far enough back to clear the trailer

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BogMonster · 31 March 2023, 19:22

I've never tried it but mine seems to take off fairly quickly if the winch line is slack. Interesting.

Peter_C · 31 March 2023, 19:52

I thought about putting three wheels onto a smaller rib and powering them hydraulically (Like Sealegs), or using an electric winch/capstan mounted in the bow of the boat for recovery by setting the anchor up the beach and pulling it out of the water (Simplest, and would make for an easy anchor recovery).

A simpler way to control launching would be to use a rope tied to the boat with a descender type device for heavy rescue attached to the trailer. The load will never be the full weight of the boat. This one is rated for 50kn/11,240#'s.

beamishken · 31 March 2023, 19:59

Quote:

Originally Posted by BogMonster

I've never tried it but mine seems to take off fairly quickly if the winch line is slack. Interesting.

It will roll fairly quickly down the trailer but once it hits the water it slows quickly & is easily checked with the painter rope once fully in the water, maybe a boats length or less away. Just make sure you have a long enough rope with plenty of slack the first few times you do it, you dont want the load going on the painter halfway off the trailer

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Iankristy · 01 April 2023, 10:05

As above, you Can just tie off the painter to base of winch post for example. The boat will decelerate in water and painter should have a little stretch in it anyway. Re painter length personally I would always have as long as possible but always just short of the prop 🤪

beamishken · 01 April 2023, 10:17

Quote:

Originally Posted by Iankristy

As above, you Can just tie off the painter to base of winch post for example. The boat will decelerate in water and painter should have a little stretch in it anyway. Re painter length personally I would always have as long as possible but always just short of the prop [emoji2957]

I agree painter short of the prop for usual use but if your going to freefall launch it will likely be too short & if tied off to winch post its likely to take load just as the boat hits the water. For launching like this the painter would need to be temporarily extended to perhaps 2 boat lengths.

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Iankristy · 01 April 2023, 10:21

Quote:

Originally Posted by beamishken

I agree painter short of the prop for usual use but if your going to freefall launch it will likely be too short & if tied off to winch post its likely to take load just as the boat hits the water. For launching like this the painter would need to be temporarily extended to perhaps 2 boat lengths.

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Fair point, guess depends on how fast rollers are. Had a roller trailer before that was too fast so put just a couple of the crappy black rollers on to make it manageable.

BogMonster · 03 April 2023, 10:41

Thanks all. The descender is interesting and would do the job, but I'll also give it a go with pure unfiltered gravity and a longer rope, and see what happens. I think the main concern is that sometimes I launch in quite shallow water (beach launch, and the gradient varies considerably with the tide) so it would tip quite violently before it hits the water and starts to slow. The other thing I've thought of is just to put a guide ring on the winch post to hold the rope in line with the jockey wheel body and stop it riding up.

Years ago a friend with a bunk trailer used to tie off a long bow line to his boat, attach it to the trailer, reverse right in and jam the brakes on and then drive forwards and pull the boat into the beach for a hands-free launch, so there's always a way!