how accurate are bathroom scales for weighing tow ball weight
cheers snap
Hi Gordon. When checking towball weight it is important that the towbar be at the EXACT same height when the weights are taken as it is when the van is attached to the car, and that weights are taken at the hitch point.
Weighbridge give only a very rough idea of towball weight because they generally weigh in 20kg increments
Towball scales are a dead set waste of money in my opinion. To check their accuracy I bought several different brands at the same time to test against a pre-determined towball weight. Not only was there not one brand within cooee of the correct weight, the difference in readings was unbelievable. All sets of scales were subsequently given away, with appropriate warnings of inaccuracy. Actually, I think I still have a set a a mate's place in Cairns if anybody wants it.
The bathroom scales method detailed in Tim's post is as accurate as you are likely to get when going it alone, and if done properly, the bathroom scales method is VERY accurate. Cheers
-- Edited by yobarr on Monday 15th of August 2022 10:27:31 PM
My bathroom scales max weight is 150kg & the previously checked Tow Ball Weight was 271kg so -
Couldn't I just mark the centre of my bit of timber & place the vertical bit from under the towball at that point with the bit of timber on a set of bathroom scales at either end. The tow ball weight being the sum of the two readings less the weight of the two bits of timber. That's the method I used to get my original reading .. only 20 years ago.
ie Just construct an appropriately sized inverted T & place that with the arms of the T resting on the two sets of bathroom scales & the vertical leg under the towball.
Of course using the thirds method described in the link allows the use of only one set of bathroom scales with a max capacity of 150Kg like mine.
My bathroom scales max weight is 150kg & the previously checked Tow Ball Weight was 271kg so -
Couldn't I just mark the centre of my bit of timber & place the vertical bit from under the towball at that point with the bit of timber on a set of bathroom scales at either end. The tow ball weight being the sum of the two readings less the weight of the two bits of timber. That's the method I used to get my original reading .. only 20 years ago.
ie Just construct an appropriately sized inverted T & place that with the arms of the T resting on the two sets of bathroom scales & the vertical leg under the towball.
Of course using the thirds method described in the link allows the use of only one set of bathroom scales with a max capacity of 150Kg like mine.
Hi Cupie. Your method would work, but you'd need to be absolutely sure that your towball weight is less than 300kg, or you may kill the scales! Zeroing the scales once the timber is in place would allow an accurate reading, but you really need to include some way of raising the drawbar so that when the weight is taken it is at exactly the same height as it is when the caravan is attached to the car. This can be done by using the jockey wheel to get to the right height, putting packers between the timber and the drawbar, or on top of your 'T' piece, and then winding the jockey wheel up off the ground. Cheers
-- Edited by yobarr on Tuesday 16th of August 2022 02:47:12 PM
My bathroom scales max weight is 150kg & the previously checked Tow Ball Weight was 271kg so -
Couldn't I just mark the centre of my bit of timber & place the vertical bit from under the towball at that point with the bit of timber on a set of bathroom scales at either end. The tow ball weight being the sum of the two readings less the weight of the two bits of timber. That's the method I used to get my original reading .. only 20 years ago.
ie Just construct an appropriately sized inverted T & place that with the arms of the T resting on the two sets of bathroom scales & the vertical leg under the towball.
Of course using the thirds method described in the link allows the use of only one set of bathroom scales with a max capacity of 150Kg like mine.
Hi Cupie. Your method would work, but you'd need to be absolutely sure that your towball weight is less than 300kg, or you may kill the scales! Zeroing the scales once the timber is in place would allow an accurate reading, but you really need to include some way of raising the drawbar so that when the weight is taken it is at exactly the same height as it is when the caravan is attached to the car. This can be done by using the jockey wheel to get to the right height, putting packers between the timber and the drawbar, or on top of your 'T' piece, and then winding the jockey wheel up off the ground. Cheers
-- Edited by yobarr on Tuesday 16th of August 2022 02:47:12 PM
My bathroom scales max weight is 150kg & the previously checked Tow Ball Weight was 271kg so -
Couldn't I just mark the centre of my bit of timber & place the vertical bit from under the towball at that point with the bit of timber on a set of bathroom scales at either end. The tow ball weight being the sum of the two readings less the weight of the two bits of timber. That's the method I used to get my original reading .. only 20 years ago.
ie Just construct an appropriately sized inverted T & place that with the arms of the T resting on the two sets of bathroom scales & the vertical leg under the towball.
Of course using the thirds method described in the link allows the use of only one set of bathroom scales with a max capacity of 150Kg like mine.
Hi Cupie. Your method would work, but you'd need to be absolutely sure that your towball weight is less than 300kg, or you may kill the scales! Zeroing the scales once the timber is in place would allow an accurate reading, but you really need to include some way of raising the drawbar so that when the weight is taken it is at exactly the same height as it is when the caravan is attached to the car. This can be done by using the jockey wheel to get to the right height, putting packers between the timber and the drawbar, or on top of your 'T' piece, and then winding the jockey wheel up off the ground. Cheers
-- Edited by yobarr on Tuesday 16th of August 2022 02:47:12 PM
Yes thanks. That's what I did
Nice one Cupie. Having the drawbar at exactly the same level is not quite as important with loadsharing suspension systems, but it is critical on the non-loadsharing types, where a 50mm difference in height can equate to a 20kg difference in apparent towball weight. Cheers
And it is likely to be so inaccurate that it isn't even funny! Couple of years ago I bought several different brands so that I could test them, as I was far from convinced of their accuracy. Not only were there HUGE differences in the actual readings they gave, but none of them was within cooee of the actual pre-determined towball weight. Gave them all away, with appropriate warnings of their inaccuracy. The only time these things would be of any use would be if they were used to check your towball weight occasionally, having already determined how inaccurate they were. For example, if your towball weight is actually 250kg but these scales read 210kg, you only have to make sure that the scales always read 210kg to maintain correct towball weight. Glad you've had a good run with yours, but it's highly unlikely they're anywhere near accurate. Actually, I still have a similar set of scales in Cairns if anybody wants them for free! Cheers
And it is likely to be so inaccurate that it isn't even funny! Couple of years ago I bought several different brands so that I could test them, as I was far from convinced of their accuracy. Not only were there HUGE differences in the actual readings they gave, but none of them was within cooee of the actual pre-determined towball weight. Gave them all away, with appropriate warnings of their inaccuracy. The only time these things would be of any use would be if they were used to check your towball weight occasionally, having already determined how inaccurate they were. For example, if your towball weight is actually 250kg but these scales read 210kg, you only have to make sure that the scales always read 210kg to maintain correct towball weight. Glad you've had a good run with yours, but it's highly unlikely they're anywhere near accurate. Actually, I still have a similar set of scales in Cairns if anybody wants them for free! Cheers
Great that you're happy with them, but I can't help wondering how you would even know if they didn't "work perfectly"? Never mind, if you're happy with them just carry on as usual! Cheers
My bathroom scales max weight is 150kg & the previously checked Tow Ball Weight was 271kg so -
Couldn't I just mark the centre of my bit of timber & place the vertical bit from under the towball at that point with the bit of timber on a set of bathroom scales at either end. The tow ball weight being the sum of the two readings less the weight of the two bits of timber. That's the method I used to get my original reading .. only 20 years ago.
ie Just construct an appropriately sized inverted T & place that with the arms of the T resting on the two sets of bathroom scales & the vertical leg under the towball.
Of course using the thirds method described in the link allows the use of only one set of bathroom scales with a max capacity of 150Kg like mine.
Hi Cupie. Your method would work, but you'd need to be absolutely sure that your towball weight is less than 300kg, or you may kill the scales! Zeroing the scales once the timber is in place would allow an accurate reading, but you really need to include some way of raising the drawbar so that when the weight is taken it is at exactly the same height as it is when the caravan is attached to the car. This can be done by using the jockey wheel to get to the right height, putting packers between the timber and the drawbar, or on top of your 'T' piece, and then winding the jockey wheel up off the ground. Cheers
-- Edited by yobarr on Tuesday 16th of August 2022 02:47:12 PM
Yes thanks. That's what I did
Nice one Cupie. Having the drawbar at exactly the same level is not quite as important with loadsharing suspension systems, but it is critical on the non-loadsharing types, where a 50mm difference in height can equate to a 20kg difference in apparent towball weight. Cheers
Hi yobarr,.
I tend to believe from my experience using a friends and now my own digital flat bed scale, "it is also necessary to have the tow hitch at the same height" when weighing load sharing.
Great that you're happy with them, but I can't help wondering how you would even know if they didn't "work perfectly"? Never mind, if you're happy with them just carry on as usual! Cheers
I could teach you how to use yours correctly if you like.
Great that you're happy with them, but I can't help wondering how you would even know if they didn't "work perfectly"? Never mind, if you're happy with them just carry on as usual! Cheers
I could teach you how to use yours correctly if you like.
Thanks for your kind offer, but I am well familiar with their operation and I've already established that they're nothing more than a rough guide. However, you seem very happy with yours, so good on you. Just don't take the reading seriously. You might like to consider that those types of scales rely solely on compressing a spring and reading off a scale, and that from day one the spring will gradually lose its strength. There is no way known that your 12 year old spring is going to be as strong it was when new. Cheers
-- Edited by yobarr on Tuesday 16th of August 2022 07:25:12 PM
Great that you're happy with them, but I can't help wondering how you would even know if they didn't "work perfectly"? Never mind, if you're happy with them just carry on as usual! Cheers
I could teach you how to use yours correctly if you like.
Thanks for your kind offer, but I am well familiar with their operation and I've already established that they're nothing more than a rough guide. However, you seem very happy with yours, so good on you. Just don't take the reading seriously. You might like to consider that those types of scales rely solely on compressing a spring and reading off a scale, and that from day one the spring will gradually lose its strength. There is no way known that your 12 year old spring is going to be as strong it was when new. Cheers
-- Edited by yobarr on Tuesday 16th of August 2022 07:25:12 PM
Similar scenario with the spring in your 12 year old bathroom scales.
