CLH Roller Wheel Alignment

[MarkF]

Please can anyone offer advice regarding alignment of the Rollers on a CLH braked trailer? I'm concerned they are not flat on the hull and will cause pressure points whilst towing.

I've looked through previous topics, but can't find exactly this issue discussed.

Qu.1) When fully on the trailer, our boat sits on the four sets of wheeled rollers and is clear of the middle rollers.  I assume the middle rollers are to support it only whilst being winched.  Is this correct?

Qu.2) The two rear sets of 4-wheeled rollers fit well and sit below the boat.  The Front pair are much further to the side (the support bar about 11cm in from the frame).  They almost line up with the side skegs.  However, because the bar is articulated but the individual wheels are not, the hull only sits on the corners of the wheels - they are not flat on the hull surface (pics attached).

Is this the correct position and will this cause hull damage with long-term trailering, due to increased pressure as the contact patch is so small?  Moving them in a bit might help, but the lateral support is still needed for safe towing.

many thanks, Mark

[Graham W]

Mark,

The weight of your boat should be fully supported at all times by the central keel rollers (middle and front) and by the various rollers making up the assembly at the stern.  The side rollers that you have photographed are intended only to stop the boat rocking from side to side when on the road, not to bear the full weight of the hull.  Hence the name wobble rollers. 

It sounds like quite a lot of adjustment to the post heights need to be made.  I suggest that you start by dropping the wobble roller posts a little so that they no lower bear any weight but still provide a bit of side support.  It might be better if you do this after you have moved the boat back on the trailer so that they are not under any stress.  Then winch the boat forward again and adjust all three sets of central rollers so that they all bear weight as equally as possible.  Finally raise the wobble roller brackets so that they give firm sideways (and equidistant) support but don't take weight off the central rollers.  If you're going to Rutland, there may be someone there who can check it out but I would try to adjust it before you go.

It can sometimes help to use a jack under the roller posts to make sure that they are providing full support.  It can be difficult to do this by hand.

[MarkF]

Hi Graham,

thank you very much for your advice.  I  seem to be stuck in a 3-way trailer conundrum!

I lowered the rollers to put the boat on the middle ones and realized there is no way I can get it onto the rear central roller, as it cannot be adjusted.  So I phone the yard...

According to the yard, the boat should be supported on the front central roller.  However, they said the middle central roller should be clear of the boat, with just the centre board resting on it.  The rear central roller is also clear of the boat.  They recommended asking CLH...

Who were also very helpful.  They checked the bolt settings and gave me the measurements that they use to setup the trailer.  Which they get from Swallow.

Turns out with these settings, the trailer adjustment was back where it started - and the front roller well clear of the keel. 

I suspect an incorrect measurement has slipped in somewhere.

[Martijn]

I Agree with Graham,

The keel is the strongest part of your boat, it should be supported by your keel rollers, if possible all of them.
The others rollers are mainly to keep your boat in place. They can bear some of the load but not too much.

[Graham W]

Mark,

Welcome to the whacky world of CLH Trailers!

I’ve just had a look under my boat in the freezing cold (unlike the rest of the UK, it’s been like this for days) and have found not three sets of keel supports but four, and all adjustable for height to a greater or lesser degree.  The front one is a plain blue 125mm roller.  Numbers two and three are 125mm rollers with a small castor each side, their support poles finely adjustable for height.  From what I can see, the keel is supported by the roller and the hull either side of the keel lightly rests on the castors, which are perfectly sized for the task.  And the stern sets of wheels  (on my trailer eight wheels in all, no roller) are the ones used by the swinging cradle to aid retrieval from the water.  All except the last are blue plastic and were retrofitted by me to replace the hopelessly deformable black ones that the trailer came with originally.

None of this helps you I’m afraid, particularly if some of your supports are not height adjustable.  I suspect that the sizing of the roller and castors in the middle two sets of my supports was a happy accident.  The roller/castor set is still being made https://shop.chastheboat.co.uk/products/trailer-spare-parts-keel-rollers-and-brackets-125mm-fixed-keel-roller-with-castors.

I don’t like the sound of the middle part of your keel being unsupported and can’t understand why this should be the case.  Surely the more places that the boat keel is supported (within reason), the better?

[MarkF]

Graham, thank you very much for venturing out to check for me.  As long as they bear the weight evenly, I can't see why the boat shouldn't be supported along its keel - makes intuitive sense.

I noticed CLH have a loyal cohort of enthusiastic followers in tow on the forum.

They were very helpful across the phone today, but something doesn't add up. Once the final adjustments were made, it seems the boat now sits well on the middle central roller.  The centre board could sit on the stern central roller.  However, there's no way the bow is anywhere near the front one.  And the measurement for winch height ensures the winching eye on the boat hits the lower rubber on the winch post. 
I'll chat again to CLH and perhaps send them a diagram of what I think they said, to ensure my ear-to-spanner communication was successful.  If it turns out I heard them right, I'll check with the yard. 

Unless the front roller arm is actually the wrong one and too short, there really is no way to get the boat to fit as intended.  Lowering the whole hull brings it worryingly close to the vicious corners of the agricultural wheel arches, so I'm not keen to entertain that approach!

Your blue rollers look like an excellent upgrade.  Maybe something I'll fit once everything is adjusted.

[Graham W]

I noticed CLH have a loyal cohort of enthusiastic followers in tow on the forum.

I see what you did there.

I’ve braved the frozen wastes of North Kent again and attach a photo of the angled supports for my front roller.  In theory, the supports could be adjusted for both angle and height, although it seems more secure to have the supports’ two bolts resting against the top and bottom of the central spine box section of the trailer, fixing both angle and height. 

My 2015 winch post whinge post included a photo which showed that the front roller supports were canted backwards https://www.swallowyachtsassociation.org/smf/index.php/topic,1182.msg8803.html#msg8803.  They’re now canted forwards and I’m not sure if this happened by itself or someone did it for me.  You can see in the attached photo a white mark where they used to be.

Assuming that the bolt placement is deliberate (not always a safe assumption with CLH), the height of the supported keel at the front is 15cm above the central spine of the trailer.  All the other rollers, and particularly my two middle ones, can then be adjusted to line up with this height.

[MarkF]

Graham,

Thank you once again for braving the Kentish elements.  Your photo shows almost exactly the setup I have.

My front roller support cants forwards on the draw bar. I can’t see how it would remain in place for long if not resting on the bolts. 

The roller is 15cm above the draw bar (same as yours). The measurement that CLH have used from the yard is a horizontal measurement from the front of the A-frame cross member. That’s also correct on my trailer.

The net result is a 6cm gap between front roller and keel (pic).  If I lower the middle supports, I end up with much reduced road clearance and not much of a gap to the wheel arches.

Currently the whole boat is slightly bow-up on the trailer. Is this usual?

I will contact CLH/yard on Monday to see if they can resolve the issue.

[garethrow]

Mark
I don't have my BR20 in the garden to check / photo, but I am pretty sure my front roller support (2020 trailer) is rather differnt to yours; it is not angled but vertical, with quite a lot of height adjustment possible. I am sure of this because last winter I trimed a few inches of the bottom of the support brackets which protuded too far down to be close to tarmac and snag the road on occassions. This may not help you though! Sorry.

Regards

Gareth Rowlands
GPR BR20 Halen Y Mor ex S17 Gwennol Teifi

[Graham W]

Mmmm…..

If your front roller is the correct height, I’m now wondering if your swinging cradle assembly at the other end of the trailer is too low.  In the attached photo, the upright holding the cradle wheels has two positions and mine is bolted in to the higher of the two holes.  The distance from the keel to the cradle bar (the part covered in a stainless steel sheet to ease friction) is 19cm.

If someone was having trouble with their stem jamming against the cradle bar when retrieving their boat (as used to happen to me), they might have been tempted to lower the stern rollers.  In fact there is a much better remedy involving extra ironmongery - see https://www.swallowyachtsassociation.org/smf/index.php/topic,1141.msg9835.html#msg9835.

If your wheel arches are getting in the way, perhaps your wheel axle is too high in relation to the trailer frame, although how that might be possible is a mystery to me.  Or perhaps the wheel arches themselves are not correctly positioned.  See the attached photo of my setup, to compare with yours.

[MarkF]

Gareth - thank you, that is helpful as I wonder if they changed the front support to one that is long enough (your trailer is newer than mine)!

Graham - thanks for the suggestion; I've checked the stern rollers and, whilst mine have more holes drilled in them, they are all at the highest setting and not adjustable in any other way.

The clearance between wheel arch and hull is 5cm one one side and 6cm on the other. 

I've chatted to CLH and sent them photos of all supports with the measurements I'd set them to.  Apparently I have followed their instructions correctly based on the measurements that SY give them.

So my last option is to contact the yard.  I'll let you know!

[MarkF]

I think we have a solution.

CLH have been very helpful and spent more time measuring bits of their setup.   Given the measurements they use, the base of the front roller support is 170mm above the draw bar. 

Whipping out some primary school maths, I noted that my roller sits at 110mm + 60mm gap = 170mm. Bingo.

So, for whatever reason, my trailer has the wrong front support.  Apparently, at some point, SY asked CLH to change to the adjustable pillar that Gareth described, presumably for this reason. Should be easy to resolve.

Thank you all for your support!

[RogerLennard]

Here's a picture of my 2022 CLH trailer with the front support, if that helps....

[MarkF]

Roger,

thank you - I think that is exactly what I need to replace my front roller with; both adjustable and tall enough.  It matches the picture CLH sent me and is presumably what Gareth was referring to. And I notice you have the new not-so-scarily-angular wheel arches!

I like your hull colour choice!

[MarkF]

Sitting (more) prettily.

Thank you all for your help and advice.