Mansfield Posted October 13, 2009 Share Posted October 13, 2009 Hello all, I am looking to buy a towing pole for recovery purposes, for on road use does any one know of any good ones (not the small Halfords type that is ok for hatch backs but not 4x4's) i am looking for on that connects to a tow ball then to front recovery point any ideas Thanks Ben Mansfield Quote Link to comment Share on other sites More sharing options...
cipx2 Posted October 14, 2009 Share Posted October 14, 2009 It depends on how much you want to spend and if you care for a certified product (I would). You can get anything from this: http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=150378531130 to one of these two 3500kg ones with spring hooks: http://intertradeuk.co.uk/catalogue_php/index.php?cPath=21_25 Quote Link to comment Share on other sites More sharing options...
ejparrott Posted October 14, 2009 Share Posted October 14, 2009 I made one like the bay one....for a lot less than £55!!! and its got three different lengths, 18", 4' and 8' - i use the 18" to move the project around the drive, and the 4' is created by not putting in the extra extension! Quote Link to comment Share on other sites More sharing options...
leeds Posted October 14, 2009 Share Posted October 14, 2009 The small ones from the likes of Halford, Machine Mart etc are not up to towing a Landy, especially the sprung loaded ones. Most rear towpoints are centrally mounted and most front towing points are off centre. This produces a bending moment on the towing pole and bends the smaller poles. Guess how I know? If Land Rovers are involved get a heavy duty one even if it is for on road use only Brendan Quote Link to comment Share on other sites More sharing options...
Guest noggy Posted October 14, 2009 Share Posted October 14, 2009 The small ones from the likes of Halford, Machine Mart etc are not up to towing a Landy, especially the sprung loaded ones. Most rear towpoints are centrally mounted and most front towing points are off centre. This produces a bending moment on the towing pole and bends the smaller poles. Guess how I know? If Land Rovers are involved get a heavy duty one even if it is for on road use only Brendan can you please explain this "bending moment"? the only way it will bend is if the vehicle behind pushes on the tow vehicle, or ofcourse if the tow vehicle brakes. towing straight forward, the pole would never bend. Quote Link to comment Share on other sites More sharing options...
Quagmire Posted October 14, 2009 Share Posted October 14, 2009 Surely a bending moment would only be produced if one end could not rotate? Quote Link to comment Share on other sites More sharing options...
Guest noggy Posted October 14, 2009 Share Posted October 14, 2009 Exactly my thoughts! Quote Link to comment Share on other sites More sharing options...
ejparrott Posted October 14, 2009 Share Posted October 14, 2009 no, think of it as a triangle, the force of the tow vehicle pushs in a straight line, but the pole is on an angle to the direction of travel, this results in the middle of the towpole being bent outwards. The longer the pole, the less force there is to bend it, the shorter the pole the stronger you have to make it. It is for this reason that I mounted my front towball in the middle of the bumper, not to the side, it may not help me when im pushing the caravan, but when i've been towed home, its much easier on a straight tow. Quote Link to comment Share on other sites More sharing options...
David Sparkes Posted October 14, 2009 Share Posted October 14, 2009 To understand the bending moment, by what seems like a perfect example of serendipity, you should read the post I reference below. Posted today, it describes the effects experienced when towing a 109 behind an 88, via a tow pole that is obviously centrally mounted on the towing vehicle, and offset on the towed vehicle. When the vehicles are straight behind one another the pole is angled. Under power the towing vehicle attempts to pull it straight, which offsets the towed vehicle to the right. In this configuration there is no bending moment. But, the driver of the towing vehicle doesn't want to drive in the gutter, so the straight pole puts the towed vehicle on or over the white line down the centre of the road. The driver of the towed vehicle steers left to avoid this, angling the pole. With the driver of the towed vehicle steering left the traction of the front tyres forces the pole one way, while the traction of the rear tyres on the towing vehicle forces the pole the other way. Combine these sideways forces with the forward pull exerted by the towing vehicle and you get the bending moment mentioned. The post I reference doesn't attempt to describe what happens (which is why I've just attempted that), but it does describe clearly what it feels like, which may help with the understanding. http://www.series2club.co.uk/forum/index.php?topic=30914.msg276297#msg276297 Quote Link to comment Share on other sites More sharing options...
ejparrott Posted October 14, 2009 Share Posted October 14, 2009 towing a 109/110 with an 88 is horrible on a pole, having done each once, i'm not in a hurry to do it again... Quote Link to comment Share on other sites More sharing options...
leeds Posted October 14, 2009 Share Posted October 14, 2009 With a central tow point on towing vehicle and an off centre tow point on vehicle being towed then on a straight road for the towbar to be straight in line of travel then the towed vehicle sits to one side of the towing vehicle. Not an ideal situation. Go around a bend with the towed vehicle trying to track the towing vehicle which is slowing down then there are component of forces not running straight down length of pole. Have a pole which is sprung loaded, that has slots cut into pole then pole bends. Hope that explains it clearly. Once towed a vehicle using one of these poles and it landed up being bent and that is the only way I can explain it happening. Hence why suggest avoiding lightweight ones if towing Land Rovers Brendan Quote Link to comment Share on other sites More sharing options...
Exmoor Beast Posted October 14, 2009 Share Posted October 14, 2009 I bought a 2T rated one to tow a series 3 project I had a while back and it was wrecked by the time I got the 20miles home. I'd rather use a trailer now. I've towed/been towed too many times with no PAS no brakes etc, it was funny once but not anymore. I must be getting old... Will Quote Link to comment Share on other sites More sharing options...
freeagent Posted October 14, 2009 Share Posted October 14, 2009 I've managed to bend one of those poels made from 50mm square tube, it was bought from Old Sodbury for abuot £30.. If I was in the busuness of towing Landies on the road regularly i'd make something ultra heavy with NATO pintle rings on either end, and fit NATO hitches to front/rear of the vehicles involved. Quote Link to comment Share on other sites More sharing options...
ejparrott Posted October 14, 2009 Share Posted October 14, 2009 Thats the sort of thing that heavy haulage boys use, and full size traction engines...i know! Quote Link to comment Share on other sites More sharing options...
tacr2man Posted October 14, 2009 Share Posted October 14, 2009 Thats the sort of thing that heavy haulage boys use, and full size traction engines...i know! Its not the size of your pole its how you use it I have had a 6" square tow pole bent , by an idiot in a 8 wheeler who could not follow simple directions about staying in line behind towing vehicle when coming to a halt as he had had his brakes wound off , I only pulled him about 150 meters to clear a junction . A 50mm sq thickwall tube should be more than man enough to tow a lr . JMHO Quote Link to comment Share on other sites More sharing options...
Phil Hancock Posted October 14, 2009 Share Posted October 14, 2009 Thats the sort of thing that heavy haulage boys use, and full size traction engines...i know! Yup the bigger one with the rubber buffers built into it that we use at the Great Dorset Steam fair takes 2 people to lift it! and a normal one is not much lighter but is liftable by one. Quote Link to comment Share on other sites More sharing options...
bishbosh Posted October 14, 2009 Share Posted October 14, 2009 Confused by the "bending moment" theories. My experience of tow poles is that it fits on the tow ball of the tow vehicle and then attaches via a shackle type conneciton to the front recovery eye of the towed vehicle. Both these connections can be considered as "pinned" connections and as such can transmit no bending moment into the pole unless they reach the limit of their travel. (which would mean you have more immediate problems to be worrying about.) The offset nature of the tow ball - recovery eye relationship will generate a sideways force, but this is easily resisted by the friction between the tyres and the road (of both vehicles). Not been a problem in my experience. I suspect that the poles bend due to be under designed and they are actually buckling due to compressive loads from braking. This is where the length v strength problem arises - the shorter the pole the stronger it will be for a given cross section but short poles mean a greater sideways force and a scarier experience for the fellow steering the towed vehicle! Longer poles need to be from a stronger section so end up being heavier and more expensive. Quote Link to comment Share on other sites More sharing options...
ejparrott Posted October 14, 2009 Share Posted October 14, 2009 My pole is ball to ball, not ball to shackle, and a heavy haulage bar is pin to pin. If the towed vehicle attempts to overtake the towing vehicle when on an offset tow, it doesnt matter what sort of attachment you have, it will still impart a bend onto the pole. The trick is not to make it too strong. It needs to be weak enough to flex so that the towed vehicle doesnt push the the towing sideways off the road, but it also need to be strong enough to do the job, and to not bend under light loading. Alternativly, use a centre tow like mine... Quote Link to comment Share on other sites More sharing options...
bishbosh Posted October 15, 2009 Share Posted October 15, 2009 My pole is ball to ball, not ball to shackle, and a heavy haulage bar is pin to pin. If the towed vehicle attempts to overtake the towing vehicle when on an offset tow, it doesnt matter what sort of attachment you have, it will still impart a bend onto the pole. No it will not. In the situations you describe the pole is a pin ended strut. As such, it cannot by the laws of physics have a mending moment applied to it from its ends. What the pole is doing is experiencing a compressive force. If this force exceeds the buckling capacity of the pole then the pole will buckle. This is the bend you may be experiencing. This is categorically not a bending moment however. You should note that in this scenario, the buckled pole will fold up VERY quickly with disastrous results if you can actually see deformation. Quote Link to comment Share on other sites More sharing options...
Phil Hancock Posted October 16, 2009 Share Posted October 16, 2009 I agree with Bishbosh its got to be buckling under excessive compressive force as with a joint at each end that is free to move there is no bending force. The F off big bars still bend but only when you get it very wrong and try to overtake the towing vehicle when braking and then its when the bar runs out of movement at one of the hitches that causes a bend. Quote Link to comment Share on other sites More sharing options...
ejparrott Posted October 16, 2009 Share Posted October 16, 2009 Get it wrong... it gets bent.. End of story, what does it matter Quote Link to comment Share on other sites More sharing options...
western Posted October 17, 2009 Share Posted October 17, 2009 Ben was with me when we used my ex-RAC intertrade towpole, the Bending part is so the towpole can be assembled with the 2 vehicles close to each other, [the bar has a elbow joint which allows the bar to fold] once both vehicles are connected as the towing vehicle moves off the towpole straightens out & then a big spring shoves a locking tube over the elbow joint & locks the towpole rigid, see 2nd photo refer to the Intertrade website link above for more info. Quote Link to comment Share on other sites More sharing options...
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