Boat to trailer straps when trailering

CJ7Rob

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#1
I understand the straps go from eyes in transoms to eyes on sides of trailer, but are they effective at such an angle? I normally use one big strap from one trailer eye over the tunnels and down to the other, but wondering if that's the safest way. Thanks
 

CJ7Rob

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#3
What boat model?

What "such an angle" are you talking about?

What "tunnels" are you going over?
204c, I meant gunnels or gunwales. It's a 23' dual axle trailer but the rear of the boat hangs over in the back almost a foot, so the straps are at an angle if I strap them. I'll have to take a pic.
 

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DennisG01

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#4
OK, gotcha. Yes, use the two straps. Two straps are better than one. Two straps are also shorter = less stretching of the strap. Plus, because the straps are going forwards, they help a bit to 'pull' the boat forward and keep it snugged against the bow stop. The angle that you are referring to is nothing to worry about - it does not decrease the effectiveness of keeping the stern planted in any way - basic geometry confirms that :)
 
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Fishtales

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#5
agree. crazy not to use them. You can always do belt and suspenders if you want but the short straps are pretty much a must.
 

glacierbaze

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#6
I am going to have to see your "proof" on that geometry. My view is that as soon as you touch the brakes, those transom straps get looser and looser the harder you brake. How can they not, with everything about the load wanting to lean forward, taking the tension OFF the straps, instead of applying tension? The only thing keeping your boat out of the bed of your truck in a hard, straight stop is the winch post, and bunk friction.
A tight 3 or 4 inch rachet strap from trainer beam to trailer beam, over the gunnels, is much more effective, IMHO. It actually gets tighter if the boat start to move forward, where the transon straps get looser. Basic geometry tells me that. And, as it tightens, it also increases bunk friction. Heaven help you in a panic stop, if you have a roller trailer and transom tie downs.
If I am towing highway speeds, it is with a 10K gunnel strap, and a safety chain from the bow eye back to the front cross member.
 

Bumpye

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#7
I had the same dilemma and struggled with a solution for quite some time. Because the angle was so sharp, I ran a heavy duty tie down over and across the gunwales. I still feel more comfortable doing it that way. Plus if I ran tie downs from the eyes on the stern, they would run across my trim tabs. I could move them to the side, but felt it would chafe the straps.
 

glacierbaze

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#8
Typical application. How far does that boat have to move forward, before the strap starts to hold it back? Two or 3 feet, at least, and by that time, the winch post is trashed. And who thinks those open, made in China, hooks are going to hold?
Geometry also tells me that if that that boat will go 3 feet forward, it will go half that distance to the side, before those straps come tight, enough to tip the balance of the trailer into a rollover. They would be much more effective going to the center of the trailer, instead of the outside.

1557968706412.jpeg
 
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DennisG01

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#9
Typical application. How far does that boat have to move forward, before the strap starts to hold it back? Two or 3 feet, at least, and by that time, the winch post is trashed. And who thinks those open, made in China, hooks are going to hold?
Geometry also tells me that if that that boat will go 3 feet forward, it will go half that distance to the side, before those straps come tight, enough to tip the balance of the trailer into a rollover. They would be much more effective going to the center of the trailer, instead of the outside.
Re-read my post. I said they help to keep the boat snugged FORWARD to the bow stop.

I tow a lot of boats... A LOT of boats (not just my own). In some cases, 700+ miles at a time and up to 34'. It is very rare that the straps loosen up. Two reasons typically cause that... worn-out straps/buckles and someone who didn't load their trailer properly to begin with (use error). The bow keel should be TIGHT against the bow stop with the bow eye snugged tightly underneath the bow stop/roller. If you do that, the boat CAN NOT move forward and the straps will not go slack.

I write this not from theory or what "seems" right. This is from 30+ years of on the road experience, along with others at the shop, etc, etc.

The theory of the boat moving 3' forward can only happen if user error is involved or the winch stand fails catastrophically due to a major accident... in which case there are worse things to worry about. In regards to the boat moving left and right, that is also false. The straps are at opposite angles to each other... just like they would be if mounted to the center of the frame. One of the straps would have to break for the boat to go sideways - the same could happen if a center-mounted strap broke. Also, the boat wouldn't really go completely (straight) to the side... it would do more rotating than sliding. But again, it would have to be a major accident where whether the boat stays on the trailer or not is an insignificant point... and again, that could happen no matter how the straps are positioned. Besides, at least you would have two straps helping - with a single strap, if it breaks, you have no help at all.
 

CJ7Rob

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#10
Thanks guys, good info to know. I guess I could use 2 short straps for the rear, and 1 over the gunnels for added security. I am only going about 40 miles but you always think and worry about these kind of things.
 

DennisG01

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#11
Thanks guys, good info to know. I guess I could use 2 short straps for the rear, and 1 over the gunnels for added security. I am only going about 40 miles but you always think and worry about these kind of things.
Although it's really not necessary, it's not like it's a bad idea, either.

One thing I'd caution on, though, is the placement of the long strap. I have personally seen, on more than one occasion, stress cracks in the top of the hull and the gunwale from an over-the-gunwale strap. Boat hulls flex - and cranking a gunwale strap down actually squeezes the sides of the hull together. Combined with the bouncing/jarring a boat experiences on a trailer, the gelcoat can crack. Not "will crack"... "can crack". From what I've seen, it has a lot to do with the placement of the strap - if it's over the aft end, where you have more structure port to stbd because of the transom and motor well, I'm sure that greatly reduces the chances.
 

glacierbaze

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#12
The OP asked for opinions, and I gave mine. I have never heard anyone else suggest that the role of a "transom tie down" was to snug the boat forward into the winch post. A google image search for 'boat trailer accidents' will show that catastrophic failure AT the winch stand is not at all uncommon, and neither is owner error. Every image I saw showed the boats going forward, or sideways, so again IMHO, most typical towers would not fare well in a panic stop, or a collision, using off the shelf tie down straps.

"The theory of the boat moving 3' forward can only happen if user error is involved or the winch stand fails catastrophically due to a major accident... in which case there are worse things to worry about"...........It is also often the case, that the boat leaving the trailer, for any reason, is what escalates what could have been a manageable situation into a major accident. We all agree that prevention is the key. And it doesn't have to be a failure of the winch stand, all that has to fail is one spring, or almost any other part of the winch itself. Do you really put a 34 footer on a trailer with only a bow strap, and 2 transom tiedowns, and tow it 700 miles? Or are there safety chains, and other measures used?
"In regards to the boat moving left and right, that is also false. The straps are at opposite angles to each other... just like they would be if mounted to the center of the frame." That would be somewhat factual, if the angles were opposing each other parallel to the transom, and more accurate the closer the angles got to a linear 180 degrees. My comments were in regard to the typical photo that I posted, where the attachment point is well forward of the transom, after the OP stated that the angle in question was the one created by his boat overhanging the trailer by a foot. Which makes your response, "
The angle that you are referring to is nothing to worry about - it does not decrease the effectiveness of keeping the stern planted in any way - basic geometry confirms that :)", factually and mathematically incorrect. The further forward the attachment point is on the trailer, the easier it is to both lift the stern of the boat, and move it side-to-side. . Think 10 feet forward, and basic geometry becomes more obvious.
 

DennisG01

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#13
Opinions are definitely welcome! One of the best ways to learn is through discussion.

A google image search for 'boat trailer accidents' will show that catastrophic failure AT the winch stand is not at all uncommon, and neither is owner error.
There's a flaw in your line of thinking/searching.... if you intentionally search for "accidents", what will the search results show? They surely won't show successful trailering trips. Accidents like we are talking about, while they do happen, are nowhere near the 'norm'.

"
We all agree that prevention is the key. And it doesn't have to be a failure of the winch stand, all that has to fail is one spring, or almost any other part of the winch itself.
Agree, certainly. But to the point of the straps help to keep to the bow snugged to the winch stand. Just because you haven't heard of that before, doesn't mean it isn't true. If the winch pawl fails, what is the first line of defense to keep the bow snugged? The straps.

QUOTE="glacierbaze, post: 169047, member: 16064"]Do you really put a 34 footer on a trailer with only a bow strap, and 2 transom tiedowns, and tow it 700 miles? Or are there safety chains, and other measures used?[/QUOTE]

Of course there are extra measures - but that wasn't the point of this thread (and I never said I didn't use extra measures) - it's about what the OP can do for his boat. It also depends on the particular trailer I am using.

"
In regards to the boat moving left and right, that is also false. The straps are at opposite angles to each other... just like they would be if mounted to the center of the frame."
That would be somewhat factual, if the angles were opposing each other parallel to the transom, and more accurate the closer the angles got to a linear 180 degrees. My comments were in regard to the typical photo that I posted, where the attachment point is well forward of the transom, after the OP stated that the angle in question was the one created by his boat overhanging the trailer by a foot. Which makes your response, "
The angle that you are referring to is nothing to worry about - it does not decrease the effectiveness of keeping the stern planted in any way - basic geometry confirms that :)", factually and mathematically incorrect. The further forward the attachment point is on the trailer, the easier it is to both lift the stern of the boat, and move it side-to-side. . Think 10 feet forward, and basic geometry becomes more obvious.
Length does not matter, though. The bow eye to stern eye to trailer attachment point (of the straps) is, in essence, a triangle. Let's make an assumption that the bow stays stationary (if it doesn't there are other variables and things happening, and that puts us down a totally different path), attached to the winch. We're simply talking about keeping the stern planted while the trailer bounces around during trailering. In order for the stern of the boat to lift/pivot upwards, the strap length (one side of the triangle) would have to increase. Another way for the stern to be able to lift is for the boat to move forward as that would cause slack in the straps. But then, we're back to a catastrophic failure of the winch stand for that to happen.

Besides, a gunwale strap wouldn't prevent the boat from moving forward, either - unless it is hooked under the cleats, for example, assuming the cleats wouldn't get ripped out. A gunwale strap won't 'tighten' - the boat could slide underneath the strap - although there would be some friction help to keep that from happening.

I certainly don't want to derail this thread too far. But I will stick with my initial/main response that the 2 straps work very well and do not pose any inherent risks. If you don't agree... Hey, that's OK!
 

gw204

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#15
Those transom straps are a joke. On anything over 18' or so I will only use a ratchet strap over the gunnels.

My old 25' Sailfish got a 10,000 ratchet strap over the stern to hold it down, and smaller ratchet strap to lock the bow eye down to the trailer.
 

RussGW270

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#16
Re-read my post. I said they help to keep the boat snugged FORWARD to the bow stop.

I tow a lot of boats... A LOT of boats (not just my own). In some cases, 700+ miles at a time and up to 34'. It is very rare that the straps loosen up. Two reasons typically cause that... worn-out straps/buckles and someone who didn't load their trailer properly to begin with (use error). The bow keel should be TIGHT against the bow stop with the bow eye snugged tightly underneath the bow stop/roller. If you do that, the boat CAN NOT move forward and the straps will not go slack.

I write this not from theory or what "seems" right. This is from 30+ years of on the road experience, along with others at the shop, etc, etc.

The theory of the boat moving 3' forward can only happen if user error is involved or the winch stand fails catastrophically due to a major accident... in which case there are worse things to worry about. In regards to the boat moving left and right, that is also false. The straps are at opposite angles to each other... just like they would be if mounted to the center of the frame. One of the straps would have to break for the boat to go sideways - the same could happen if a center-mounted strap broke. Also, the boat wouldn't really go completely (straight) to the side... it would do more rotating than sliding. But again, it would have to be a major accident where whether the boat stays on the trailer or not is an insignificant point... and again, that could happen no matter how the straps are positioned. Besides, at least you would have two straps helping - with a single strap, if it breaks, you have no help at all.

Good points Dennis. I have been wondering why the boat I got did not have straps on it, and I have not seen anyone with straps. I had assumed people did not use them because they felt a 4-ton boat would not move OR that the straps would not hold if it did move.

Before I get on the road, I plan to locate a couple solid straps to use... even if to only give me a warm fuzzy feeling heh.

R