Ratchet Strap Protectors

[PeterDT]

Imho the straps should never ever get loose. Using the ratchet and tightening it untill the boat starts to moan slightly and you can play the bass on the straps, and securing the ends, they never slip in my experience. This is essential to prevent misshaps if ever you have brake hard or the trailer starts swinging.
There will be no damage to the hull, if the boat is any good and good protection pars are used. Imagine the forces on the hull in a 6 Bft breeze, going upwind in 1,5 m waves.
Safe trailering,
Peter DT
BRe 7 Anna

[Graham W]

I use two ratchet straps with gunwale protectors and have never suffered from loose hook misery, even on my trips to Greece. I stop and check everything (including bearing temperatures) every couple of hours or so.

On the other hand, it is possible to over-tighten, resulting in a bit of hull redesign.  I've seen the results and it's not pretty.

[Peter Cockerton]

Graham and Peter

I can only think of a couple of reasons why we are having different experiences on this loose hook misery as Graham describes it, one being that the strap is not being tensioned enough to absorb any flexing in the hull as I think we all agree is at the root cause and perhaps another reason being trailer design.

On my old Bramber trailer the stern was only supported by the swinging cradle rollers as no keel roller on the stern area of the trailer. As the tension is applied I can see the hull being flexed at this point against the rollers, with no suspension too talk off on the trailer as the boat bounces along the road the hull will flex even more around the cradle rollers. If the initial tension which Peter describes is hard (hull moans slightly) then the hull is flexed probably to its furthest point and will not move anymore with the boat bouncing along the road.

Imho tensioning the strap to this extent does not sit well with me so I,m going to see if I can find some of the straps which Simon has mentioned or make a short loop of 12mm shock chord to loop onto the hook end of the strap and to the welded loop on the trailer to help absorb the flexing without extreme stresses on the hull.

[Sea Simon]

I too am very anxious about any possibility of overloading or deforming the hull.
Have seen it happen with racing dinghies, luckily not mine!

Bungy ratchet straps...
..see 
Shockstrap.com
Not sure about any UK dealers?

But at those prices, maybe TimLMs  nylon ropes are worth trying first?

[Matthew P]

As I'm guilty of provoking a diversion from the "Problems to Look for" from hull damage to loose strap misery, perhaps it's time to return the subject to this post, where it belongs.

Attached is a strapping plan that seems to have worked so far without damaging my BR20 or finding it AWOL from the trailer.  The basic principle is to route the straps through the only two points of support so that the boat and trailer can flex independently but the straps are not subjected to stretch or loosening. 

In addition straps are routed over the strongest parts of the hull and sloped to restrain the boat from moving backwards or forwards.

TimLM makes an interesting point about the need for some elasticity in the system to absorb minor stretching and slackening. Perhaps someone might do the difficult sums to work out the optimum strap elasticity to hold the boat in place but provide enough "give" to withstand strains induced by boat/trailer flexing without overloading the boat or trailer. Not all of us have Tim's experience and feel to get this right.

Although a strap attachment plan is effective, loose strap misery is so serious that an additional belt-and-braces, fail-safe and convenient way to prevent hooks from detaching is worthwhile.  Better that the strap remains attached, even if it is actually loose. Straps routed right around hull and trailer might be the answer although I dislike long lengths of strap fluttering in the wind.  Incidentally, fluttering straps can be be claimed reduced by putting a single twist in them over long spans.  I have no evidence to support this idea but do it anyway.

Please note my disclaimer - the strap scheme suggested here may not be suitable for other boat and trailer combinations and it's up to the driver to ensure that their system is safe and secure.

Matthew
BR20 Gladys

[Peter Cockerton]

I commented with this post under

https://www.swallowyachtsassociation.org/smf/index.php/topic,1998.0.html

but quite rightly it was pointed out that it would be more relevant under this post so here it is again. Perhaps others who responded may wish to transfer their comments as well to make it easier for the information to be found on subsequent searches on this subject.

With the standard winch straps that hook onto the sides of the trailer and then to the ratchet assembly i believe owners over tighten these straps to overcome the hooks becoming dislodged from the trailer eyes when the boat flexes as it is being towed. Then  having stopped some distance along the journey find the straps floating and this time tension a little harder, this is my experience anyway. I have just purchased two new straps straps that go under the hull, then over the hull and back to the ratchet assembly (endless design) these will work fine i think and be kinder to the hull.

https://www.ebay.co.uk/itm/Ratchet-Straps-Tie-Down-5-5-Metre-x-50mm-ENDLESS-5-tons-Lashing-Handy-Straps/362763270947?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

[Graham W]

The online Ratchet Shop sells endless straps by weight limit rather than by width, dividing their offering into above and below 3,000 kg.  If the boat weighs around 500 kg and stops suddenly from 60 mph, can an engineer please tell me what approximate weight limit to go for?  It doesn't seem to make a great deal of difference, price-wise.

[Matthew P]

A sensible friend suggested straps with snap hooks might avoid strap un-hooking misery.  For instance see: www.theratchetshop.com/ratchet-straps/ratchet-straps-above-3000kg/5000kg-ratchet-strap-snap-hook.html    It would be worth checking whether the hooks will fit through the trailer strap attachment points.

From the descriptions on the Ratchet Shop 2000Kg, 3000Kg and 5000Kg straps are all 50mm wide and with little cost difference, so unless the buckles and hooks for stronger loads are bulkier and won't fit then it seems best to to play safe and go for 5000Kg, which will allow for future wear and UV damage.

Note that with straps this strong there will probably be very little elasticity in the strap so it'll be the boat structure that absorbs over-tightening.  I think routing straps so that they don't experience tension and slackening as the trailer flexes is the key - reference "Strapping Plans" below.   

Matthew
BR20 Gladys

[Graham W]

Thanks Matthew.  I suppose the alternative is to have open (non snap) hooks on the straps but to close them off, once they are in place hooked on to the trailer, with home made Dyneema shackles.  I would make quick release versions to avoid too much fiddling about.  I can see that I have more happy time with my knitting circle ahead of me!

[Sea Simon]

Firstly, in support of Peter Cs post 24/4, here is my miss-post from the survey thread::

The topic of ratchet straps, and associated damage was discussed on here, at
"ratchet strap protectors". It's important, imho.
https://www.swallowyachtsassociation.org/smf index.php/topic,1905.msg12569.html#msg12569

We are dealing with a flexible trailer, flexible boat, and stretchy (to some degree) straps. I wouldn't like to say which is "stiffest"?
Unlike my racing dinghy, my BRe and its trailer don't seem to bounce along the road, guess that's due to the all up weight? So, I figure that the straps are locating the load on the trailer, as opposed to attempting to create a "solid" load unit? My philosophy is therefore to try to ensure that the load can't shift significantly on the trailer, fore, aft, or sideways.
On my trailer, the keel rollers seem to take most of the boat weight, once loaded, with the swing beam and side rollers predominantly giving location? Is this right?

However, on my light (hull is less than 80kg) racing dinghy, i feel the need to be much more careful with securing the hull.
Being so light and insignificant a load, the temptation to speed is always greater. I have a serious sense of self preservation when towing the BRe!

I have made up a "spreader beam" from wood, this sits across the cockpit at the end of the dagger board case, right where the main sheet attachment turret is, a hard point. This coincdes with the wide bunk of the launch trolley. The wide securing strap goes cross the top of this.
These "hard points" in the assembly matter, imho. Don't strap tightly across wide, flat, unsupported panels.

.... I never  did buy any of those fancy bungy-based straps, in other post, but then I've not towed my BRe significantly over the past couple of years.

[Sea Simon]

Re Matt Ps unhooking misery.
Imho, this part of the problem is easily solved?
Either per my post here on 29/7/19: cut the claw-hooks off and use shackles or carbine clips.
Or, buy the new straps with clips fitted.
At last then it won't be necessary to risk overtightened straps, so as to hold the hooks in place.

Sizing/rating of straps is much harder. I'd wager not many Professional Engineers would risk their "licences" in pronouncing an exact rating, unless being paid to do so?

I see a fair bit of dynamic loading, and "known unknowns" in my business. The lifting (although strictly speaking we are not lifting here!) Systems have several dynamic load lift factors applied (to the load, the configuration of the lift gear, to the dynamic loads predicted) to achieve a required rating. On top of that, the maintenance and inspection regimes of the system are also enhanced, to account for onerous duty.
We might end up with a factor of safety of at least two, or as much as 4.5 for certain critical "man-riding" applications.

So, in short, for use on my boat ... I use the "best"available to me at the price I can afford!

[Graham W]

The J hooks on the straps are not how I remembered them, so my Dyneema shackle idea won't work.  Snap hooks it is, then.

CLH trailers, for all their faults, have three keel rollers while Bramber have two, so the opportunity for the boat to flex in the middle is reduced.  The middle roller also supports the centreboard in transit.

[Graham W]

My new 5,000kg ratchet straps with snap hooks have already arrived.  The snap hooks are quite large but fit easily on the attachment points on my CLH trailer.  So, no more over-tightening to stop the hooks coming off.