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Old 02 October 2009, 07:24   #1
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Using trailer extension pole

How do you use an extension pole?

There is a great one on my trailer but I think it could be done in a better way.

Mine has a coupling each end so it is only suitable for use under gravity - basically as a rigid rope. If you try to push the trailer with it I would have thought it would go all over the place.

If you had some square section tube in a square channel then you could actually push the trailer with it as well. For example if you were reversing on a flat sandy beach the pole I have at the moment would be all over the place I would have thought.

Also I would have thought with a round pole like mine the jockey wheel needs to be down which means that there is a lot of stress on it.

With a square tube in a square hole it would be rigid enough to support the trailer - basically a true extending drawbar.
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Old 02 October 2009, 09:01   #2
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Codders

The pole like yours(!) I have only ever seen being used to recover and not launch. Under load they work quite well, but only if no significant turns required, i.e. a straight pull. Jockey needs to be down, so no rough stuff.

For launch, gravity is normally used, though I have seen the extensive sand at the bottom of the Mumbles slip at low tide.

Steve
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Old 04 October 2009, 14:51   #3
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Originally Posted by codprawn View Post
Mine has a coupling each end so it is only suitable for use under gravity - basically as a rigid rope....If you had some square section tube in a square channel then you could actually push the trailer with it as well....With a square tube in a square hole it would be rigid enough to support the trailer - basically a true extending drawbar.
Cod - perhaps I'm missing something but is the cross sectional shape of the tube important? is the key thing not how the extension connects to the trailer. I assume yours has a "tow ball" on the end to do this and leaves you a flexible coupling. But could you not achieve what you want with a round cross section (in a round or square larger section - or even going into a few "U" brackets?)?
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Old 05 October 2009, 03:32   #4
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Originally Posted by Polwart View Post
Cod - perhaps I'm missing something but is the cross sectional shape of the tube important? is the key thing not how the extension connects to the trailer. I assume yours has a "tow ball" on the end to do this and leaves you a flexible coupling. But could you not achieve what you want with a round cross section (in a round or square larger section - or even going into a few "U" brackets?)?


I think cod means a square tube sliding in a square section that is fixed to the trailer so it doesn't articulate at the car tow hitch and the trailer hitch.

We used to use a 6 m one for the sail boat it was fine and when pushing had someone guide the trailer from the hitch just to keep it about right
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Old 05 October 2009, 04:29   #5
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I think cod means a square tube sliding in a square section that is fixed to the trailer so it doesn't articulate at the car tow hitch and the trailer hitch.
I got that - I was really just wondering why it needed to be square section/square tube? Could he not make some simple mods using the existing round section tube he has?
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Old 05 October 2009, 04:40   #6
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I got that - I was really just wondering why it needed to be square section/square tube? Could he not make some simple mods using the existing round section tube he has?
Round tubes are very strong only if they are in compression or tension, they have very little strength if they are under any sort of sideways force they tend to fold.

So if it was inside a square section it would soon bend where the two met.
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Old 05 October 2009, 05:09   #7
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Round tubes are very strong only if they are in compression or tension, they have very little strength if they are under any sort of sideways force they tend to fold.

So if it was inside a square section it would soon bend where the two met.
Ah! An engineering reason.
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Old 05 October 2009, 08:11   #8
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Jockey needs to be down, so no rough stuff.
Inflatable jockey? I've bounced over a couple of evil surfaces with mine.
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