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I'll do that Gary, thanks. I first need to get a quote for the fabrication of the cradle. If it's not too much trouble to get the hole specifications I would appreciate it. SS seems the best option although at a price.
Can you give me an idea of how much is reasonable for the cradle fabrication?
Down here in Cornwall things can either be much cheaper than elsewhere or much more expensive, depending on what it is. Builder's, for instance, seem to charge pretty much what they like as there is so much demand for barn conversions etc.
I managed to come by some top quality food grade ss which was worth about £200, but obviously thats not neccessary, so if you go for 5mm ss it shouldn't cost more than £60-£75 plus someone to fabricate it, sometimes its cheaper to go to a proper fabricating company with the plans and ask them to give you a quote including materials so you only pay for the steel you need and not for a whole sheet.
The whole job including materials shouldn't cost more than £175-£200
I'll get the hole dimensions sorted out for you over the weekend mate
I'll do that Gary, thanks. I first need to get a quote for the fabrication of the cradle. If it's not too much trouble to get the hole specifications I would appreciate it. SS seems the best option although at a price.
Can you give me an idea of how much is reasonable for the cradle fabrication?
Down here in Cornwall things can either be much cheaper than elsewhere or much more expensive, depending on what it is. Builder's, for instance, seem to charge pretty much what they like as there is so much demand for barn conversions etc.
Also Brian you'll need 4 socket head bolts for mounting it, 2 of the bolts you take out from the tow brackets can be used for the 2 back most bolts as in the pic also note you will need to trim the edge off of the tow brackets to refit them
I managed to come by some top quality food grade ss which was worth about £200, but obviously thats not neccessary, so if you go for 5mm ss it shouldn't cost more than £60-£75 plus someone to fabricate it, sometimes its cheaper to go to a proper fabricating company with the plans and ask them to give you a quote including materials so you only pay for the steel you need and not for a whole sheet.
The whole job including materials shouldn't cost more than £175-£200 I'll get the hole dimensions sorted out for you over the weekend mate
Gary,
I've emailed an engineering firm I have used in the past for a fabrication quote. Did you get a chance to sort out the hole dimensions?
As my weak point is anything electrical I wondered if you could clarify something for me. To quote a statement on the 4x4winches.com website
"A CAR BATTERY is designed to provide a lot of power for just a few seconds, i.e. to crank an engine, or a few amps power for a much longer period, whilst being recharged from an alternator. Electric winches require extreme levels of power 150-400amps (2 - 4 kW) for a long period of time and there lies the weakness."
What is your opinion of this comment? Are they just trying to sell the benefits of the more expensive hydraulic winches?
I've emailed an engineering firm I have used in the past for a fabrication quote. Did you get a chance to sort out the hole dimensions?
As my weak point is anything electrical I wondered if you could clarify something for me. To quote a statement on the 4x4winches.com website
"A CAR BATTERY is designed to provide a lot of power for just a few seconds, i.e. to crank an engine, or a few amps power for a much longer period, whilst being recharged from an alternator. Electric winches require extreme levels of power 150-400amps (2 - 4 kW) for a long period of time and there lies the weakness."
What is your opinion of this comment? Are they just trying to sell the benefits of the more expensive hydraulic winches?
Thanks
Hi Brian
when it stops raining here i'll get the dimensions for you.
As for the power consumption, when using the winch you need to keep the engine running and a good idea to use the idle up switch, once you've finished winching the batteries will soon recharge up to full, and as there are 2 big batteries it shouldn't be a problem
I've emailed an engineering firm I have used in the past for a fabrication quote. Did you get a chance to sort out the hole dimensions?
As my weak point is anything electrical I wondered if you could clarify something for me. To quote a statement on the 4x4winches.com website
"A CAR BATTERY is designed to provide a lot of power for just a few seconds, i.e. to crank an engine, or a few amps power for a much longer period, whilst being recharged from an alternator. Electric winches require extreme levels of power 150-400amps (2 - 4 kW) for a long period of time and there lies the weakness."
What is your opinion of this comment? Are they just trying to sell the benefits of the more expensive hydraulic winches?
Thanks
Hi Brian
Here are the dimensions on the pic will also email them too you
I've emailed an engineering firm I have used in the past for a fabrication quote. Did you get a chance to sort out the hole dimensions?
As my weak point is anything electrical I wondered if you could clarify something for me. To quote a statement on the 4x4winches.com website
"A CAR BATTERY is designed to provide a lot of power for just a few seconds, i.e. to crank an engine, or a few amps power for a much longer period, whilst being recharged from an alternator. Electric winches require extreme levels of power 150-400amps (2 - 4 kW) for a long period of time and there lies the weakness."
What is your opinion of this comment? Are they just trying to sell the benefits of the more expensive hydraulic winches?
Thanks
Sorry to butt in,
They are right about the chances of the plates distorting due to the sustained heat and they may short themselves out if they touch.
2kw or anything close to that is a lot of heat to dissipate and if the batteries are not vented well than there is a chance of a big expensive bang. I have heard of them exploding but have never seen them go myself.
Don’t know too much about modern battery construction but they went with regularity back in the day and the acid made more than a mess.
I used ex submarine batteries on my solar system in Spain so usually low charge low drawdown and although the stack was 25kw they did get mighty hot when under sustained load for any time .
Sorry to butt in,
They are right about the chances of the plates distorting due to the sustained heat and they may short themselves out if they touch.
2kw or anything close to that is a lot of heat to dissipate and if the batteries are not vented well than there is a chance of a big expensive bang. I have heard of them exploding but have never seen them go myself.
Don’t know too much about modern battery construction but they went with regularity back in the day and the acid made more than a mess.
I used ex submarine batteries on my solar system in Spain so usually low charge low drawdown and although the stack was 25kw they did get mighty hot when under sustained load for any time .
You probably know a lot more about this than me, but I was under the impression the heat was generated by/at the motor. Does the battery also heat up in relation to the amount of power drawn from it?
You probably know a lot more about this than me, but I was under the impression the heat was generated by/at the motor. Does the battery also heat up in relation to the amount of power drawn from it?
To a certain extent yes, if you've ever touched a battery when its on charge you will feel it is warm.
The way to use a winch is to use it in small bursts so as to give the motor and batteries time to cool and not overload them
To a certain extent yes, if you've ever touched a battery when its on charge you will feel it is warm.
The way to use a winch is to use it in small bursts so as to give the motor and batteries time to cool and not overload them
Understand that when you charge a battery you are pumping power into it, so it warms up. So when power is drawn from it why does it get warm. Is it just the passage of power, no matter which direction?
Gary’s got it covered. Like all good things little and often.
Yes batteries gas up big time when under sustained load and the emissions are highly volatile. There are especial regulations regarding charging bays etc for this very reason.
The main reason batteries come to the end of their useful life is because of sediment build up and/or buckled plates. This is often spoken of as one cell has gone.
The plates become buckled usually by the sustained load of winter cranking. They are just not designed to do this. Once they short out then the battery is US.
As can be imagined it takes a lot of current to do that although the method of construction regarding the plate separators are different with high discharge rate batteries.
Batteries will never die if they are treated properly and there are plenty of examples around in old watermills etc that are 100 years plus.
Glad for once to have something to contribute.
Paul
Understand that when you charge a battery you are pumping power into it, so it warms up. So when power is drawn from it why does it get warm. Is it just the passage of power, no matter which direction?
Told you electricity was my weak point!!
If you imagine a 5amp cable for a table light or similar you would have the mains at one end and the lamp at the other. If you substituted the lamp for a high load ,say a three kilowatt electric fire then the cable would become very hot and start to break down “under load” if the cable were not fused at its correct rating i.e. 5 amperes.
Consider your battery is designed to do similar to the cable and deliver up to five amps continuously as it would happily do all day long but for an extended period it is called upon to exceed its rating it will become hot like the cable and eventually “break down”.
Cranking a truck like ours probably requires something in the order of 1000+ amps but for a very short time and the battery probably looses only twenty percent of its charge during the typical crank.
However a winch sometimes requires continuous power for far longer than a typical crank takes and as a result discharges beyond its critical level (not sure that’s the right term) resulting in gas bubbles forming on the positive element. These gas bubbles increase resistance and the hotter things get.
That’s why the resistance of the cells is measured on a battery test rather than/as well as the voltage.
Modern car batteries have thin plates that make up the plates (larger surface area but more prone to distortion) and are not ideal for continuous loadings.
Truck /Tractor batteries have thicker plates and are designed to take the longer crank cycles that are required by some heavy diesel engines.
I hope that helps although it’s not particularly concise.
Thanks Namira that does help clarify things. I suppose the fact the Surf has two large batteries helps matters when winching? Apart from feeling the battery, to check if it's getting hot, is there any other way of telling when the load has been on too long?
I know that the Amazons and many other 4x4’s and Toyotas have twin batteries as sometimes they carry a lot of extras like spot bars and stuff and are used in extreme conditions so require a decent high current package and it is simpler to have two regular batteries than find the space for one large one and of course the weight distribution is tricky with only one as they are very heavy so that’s one of the reasons they fit two.
Do you have high current extras like that ?
How do you know your batteries are taking a hammering ?
Well as Gary suggested it takes a bit of skill to use a winch and if it’s set up ok you should be able to pull yourself or others out easily with just short pulls although I know sometimes you see shots of trucks being pulled up steep inclines for what seems like ages.
I think they must have split chargers like one finds on boats otherwise if the batteries fail they are in the mire big time.
There is no practical way to tell although the amount of gassing might help but it’s difficult to see in a conventional battery. You would have to open the bonnet and listen for the activity and look for the vapour discharge but as you can guess that’s a no no when you’re stuck and want to pull yourself out. Slow and gentle just like the ladies like is the way.
I'm no expert though.
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