Author Topic: Finally, recovering straight on a CLH trailer?  (Read 32503 times)

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Jonathan Stuart

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Finally, recovering straight on a CLH trailer?
« on: 19 Jul 2015, 22:33 »
I know I'm not alone in having had problems recovering the boat straight on a CLH trailer. Each summer over the past 3 years I've spent time staring at the trailer trying to understand why the boat never goes on straight. I've measured and adjusted various parts of the trailer, but to no avail. When viewed from behind the trailer, the boat always ends up too far to the right, even though for the first half of the recovery the boat looks to be centred.

This weekend I was thinking about this again and, without the boat on the trailer, noticed the rear rollers didn't quite point straight down the centreline of the trailer. I measured their heights and distance from the centre, etc, and everything looked fine. But the more I looked the more I felt that the "aim" of the pair of rear rollers wasn't straight down the centre of the trailer but was a few degrees to the right. Each end of the swinging cradle was bolted to the Trailer's A-frame's arms at the same point (7cm from their ends) but the rollers' aim seemed to be slightly off.

So before recovering the boat today, I loosened the clamp that attaches the right side of the swinging cradle (when viewed from behind the trailer) to the trailer and knocked it forward. I did this until the area between the rear rollers appeared to point directly through the keel rollers. In the end I knocked the right side of the cradle forward by 1.5cm.

When I recovered the boat it came on dead straight first time. I didn't even need anyone to push or pull on the boat during recovery, it just came on straight. That's the first time that's ever happened and I'm confident I may have fixed the problem.

While the swinging cradle is bolted correctly perpendicular to the trailer's A-frame, I suspect the A-frame is not quite correctly aligned with the trailer's centreline. I think the boat wasn't coming straight on to the trailer, and as the winch pulled the bow on to the centreline the stern pivoted across. Re-aligning the swinging cradle made such a dramatic difference today that I think this might have fixed the problem. Fingers crossed.... :-)

Jonathan

Ex - BayCruiser 26 #11 "Bagpuss"
Ex - BayRaider Expedition #3 "Mallory"

Jonathan Stuart

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Re: Finally, recovering straight on a CLH trailer?
« Reply #1 on: 18 Aug 2015, 09:12 »
Since making this change I've recovered the boat 3 times. Every time it has finished straight and central on the trailer and at the first attempt. I am on the verge of saying that recovery is easy and a pleasure! I think the problem is fixed and the issue with the CLH trailers was a problem with their geometry being out of the intended alignment.
Jonathan

Ex - BayCruiser 26 #11 "Bagpuss"
Ex - BayRaider Expedition #3 "Mallory"

Rob Johnstone

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Re: Finally, recovering straight on a CLH trailer?
« Reply #2 on: 19 Aug 2015, 22:47 »
I suspect the CLH alignment jig is non - existent. I had bad tyre wear with Vagabonds trailer and had to make similar "agricultural" adjustments to the axle mounts to square the axle up so that the distance from the tow socket to the axle was the same on each side of the trailer. Tyre wear fixed (but remember to adjust the brakes)!

Rob J
Rob J
Matt Newland designed but self built 15ft one off - "Lockdown". Ex BC23 #10 "Vagabond" and BC 23 # 54 "Riff Raff"

david

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Re: Finally, recovering straight on a CLH trailer?
« Reply #3 on: 20 Aug 2015, 05:51 »
Wow, ED trailers are looking better and better!
David

Ex - BR 20 - Nomad

david

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Re: Finally, recovering straight on a CLH trailer?
« Reply #4 on: 20 Aug 2015, 05:52 »
Oops. Fat fingers. I mentioned to say "EZ".
David

Ex - BR 20 - Nomad

Graham W

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Re: Finally, recovering straight on a CLH trailer?
« Reply #5 on: 20 Aug 2015, 06:47 »
I think EZ specialises in boats but CLH also make this (below) and several other kinds of trailer.  If the load won't go on straight, just whack it with a stick or set the sheepdog on it.
Graham
Gunter-rigged GRP BR20 #59 Turaco III

Jonathan Stuart

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Re: Finally, recovering straight on a CLH trailer?
« Reply #6 on: 20 Aug 2015, 15:18 »
Rob,

Yes, that's clearly one and the same issue where (mis)alignment of the outer arms means the axle and swing beam aren't perpendicular to the trailer's centreline. I had my axle replaced last year by a local firm as part of converting to a braked trailer, but you've made me think I must check it's alignment...
Jonathan

Ex - BayCruiser 26 #11 "Bagpuss"
Ex - BayRaider Expedition #3 "Mallory"

Rob Johnstone

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Re: Finally, recovering straight on a CLH trailer?
« Reply #7 on: 31 Aug 2015, 13:01 »
A little off topic but related to trailer set up and alignment. I've discovered why Vagabond is so reluctant to leave her trailer - the outer rollers on each side the "swinging"set at the back of the trailer are directly in line with the little "keels" on either side of Vagabond. The aft end of these "keels" is forward of the rollers when Vagabond sits on her trailer. I can move the roller assemblies  from side to side to overcome this but, because of the nature of the swinging bar, it means that these rollers will be lifted up (if they are set further apart) or lowered if set further together. My inclination is to set the rollers further apart by about 3 inches.

My question is how this will affect their action when recovering the boat? Does anyone have any experience of this?
Rob J
Matt Newland designed but self built 15ft one off - "Lockdown". Ex BC23 #10 "Vagabond" and BC 23 # 54 "Riff Raff"

Richard Mollart

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Re: Finally, recovering straight on a CLH trailer?
« Reply #8 on: 01 Sep 2015, 09:00 »
This all sounds so familiar. I have a CLH trailer for my Sailfish 18 (funds don't run to a Swallow at this stage). I managed to correct the alignment on mine by inserting some stainless steel washers at the appropriate place and now it comes on straight. Prior to that I had been advised that the gap between the rollers on the swing beam should be about 150mm ie just wider than the keel. It was suggested that if it is much wider this could allow the boat to veer off line as it is recovered. However, I think that it is the misalignment of the rollers that was the main cause of my boat not coming up straight when recovering.

Andy Dingle

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Re: Finally, recovering straight on a CLH trailer?
« Reply #9 on: 02 Sep 2015, 20:46 »
Hello Rob.

Just seen your post - I too have exactly the same problem on my Snipe trailer
When Equinox is fully on the trailer the rollers lie behind the little bilge keels, which of course then get in the way when launching, involving some grunt to get the boat over the top of them to get the boat moving. I've tried moving the rollers further apart to try and clear them, both trying to get the rollers on the inside and outside of the keels, even trying to get the keels 'between' the rollers. Nothing worked. The wider apart you put them, the less likely the boat will 'centralise' on the trailer - really making the problem worse, so would warn against this - I have in fact, put my rollers back to the original position as set up by SB.
The only solution I can think of is to use the 'back winching' principle or even mounting a separate winch just for 'reversing' the boat back off the trailor. Either way, I think, is a cheap and effective solution.
I'm on a pontoon at the moment but as the winter approaches I will be retreating inland again to launch and recover off the trailer so will be utilising this idea, I'll let you know..

Andy

Rob Johnstone

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Re: Finally, recovering straight on a CLH trailer?
« Reply #10 on: 04 Sep 2015, 17:25 »
Hi Andy,
Thanks for the bad news about recovery with the rollers set wider apart. I had suspected as much.  I saw our glorious leader use the "winch off" method at the LBS last year. When I tried to emulate the method, I lead the winch strop under one of the trailer cross members and then on to eye on the bow waterline. But the friction of the arrangement round the cross member was too high for me to move anything. Next time I launch VB I'll try to tuck the strop between her keel and the first roller and see what happens.

Rob J
Matt Newland designed but self built 15ft one off - "Lockdown". Ex BC23 #10 "Vagabond" and BC 23 # 54 "Riff Raff"

Andy Dingle

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Re: Finally, recovering straight on a CLH trailer?
« Reply #11 on: 06 Sep 2015, 18:35 »
Rob. Yes.. I agree. I put the strop back to the first cross member (that supports the forward rollers) back around the bow above the eye which stops it sliding down then looped on itself around the forward cross member again, winching then pulls the boat back to a point that it is a lot easier to slide it off the trailer.
This is a bit inelegant and there is a very real danger you may have get your feet a little wet..

I saw the use of a separate winch on a Cape Cutter 19 (I think it was) complete with a block to the rear of the trailer that I thought was a far more practical approach. It seems this is a fairly common problem with boats the size/weight of ours.

Cheers

Andy

Peter Taylor

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Re: Finally, recovering straight on a CLH trailer?
« Reply #12 on: 07 Sep 2015, 06:32 »
I recently launched Seatern for the first time and had the opposite problem!  Having lubricated all the rollers with Lithium grease spray so they spun freely, Seatern slipped off the trailer so fast and easily that I managed to launch a friend (who had a tight hold on the painter) at the same time!

Older and wiser as they say!
peter
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Graham W

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Re: Finally, recovering straight on a CLH trailer?
« Reply #13 on: 02 Oct 2015, 11:19 »
Going back to Jonathan's original post, my boat usually goes on straight on to the trailer at the front (now that I have a guide to keep the winch line centred) but the stern is increasingly skewed to starboard.  Jonathan talks about his boat going over to the right but I think that probably refers to the whole boat and I can see (I think) why the right hand side of the swinging cradle being too far back might have that effect.

Before I had my winch line guide, the whole of my boat often ended up to port, which following Jonathan's advice seems to mean that the left hand side of my swinging cradle is too far back.  I've now looked at it several times and I really can't see any difference.  However, if that is the case and I've cured one problem with the winch guide, I've caused another by not getting the swinging cradle correctly aligned.  Before I get my spanner out, does anyone agree?

Despite having two ratchet straps securing the boat to the trailer, I also find that the problem has solved itself by the time I get home.  A bumpy drive over the Berwyn Mountains seems to bounce the stern back into position. On the whole though, I'd prefer the boat to go on correctly from the beginning.
Graham
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Graham W

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Re: Finally, recovering straight on a CLH trailer?
« Reply #14 on: 04 Oct 2015, 20:33 »
My hate-hate relationship with my trailer continues.  Minor details like not going on quite straight pale into insignificance compared to what happened today (first photo).

I had already launched the boat when I noticed that the winch post was leaning over at an odd angle.  The post base had almost completely sheared at the bottom, at a point where there appears to have been some less than perfect welding.  My failsafe strop was also attached to the winch post, so was effectively useless. Luckily, the boat was secured to the trailer with two ratchet straps as well, otherwise it could have been quite serious.

As I said somewhere else, the boat trailer always seems to be the one part of the trailer sailing experience that is destined to provide nasty surprises.  Using the boat, by contrast, is usually an unalloyed pleasure.

I'll be taking this up with the trailer manufacturer in the morning - name prominently displayed on the second photo.  I managed to get the boat back on to the trailer with the help of the two ratchet straps (slow and difficult) and the mainsheet (fast and fairly easy).

PS If you look up this fault on Google, it is surprisingly common on boat trailers and has led to some nasty accidents.  The answer seems to be to find a way of securing a failsafe strop or chain to somewhere other than the winch post.  And maybe not relying just on the boat's towing eye.
Graham
Gunter-rigged GRP BR20 #59 Turaco III