David Jenkins
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| posted on 10/7/13 at 03:49 PM |
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Yes - you'd probably need to use just one to get consistent results, moving it from wheel to wheel as needed. At around £5 for one bathroom
scales I wouldn't expect any accuracy, but it wouldn't matter as long as they gave a consistent needle deflection for a given weight.
I have a long-term project to build a gauge based on a brake cylinder, but I was just pondering how people managed to use bathroom scales to balance
their cars.
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Bluemoon
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| posted on 10/7/13 at 03:54 PM |
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quote:
Originally posted by David Jenkins
Yes - you'd probably need to use just one to get consistent results, moving it from wheel to wheel as needed. At around £5 for one bathroom
scales I wouldn't expect any accuracy, but it wouldn't matter as long as they gave a consistent needle deflection for a given weight.
I have a long-term project to build a gauge based on a brake cylinder, but I was just pondering how people managed to use bathroom scales to balance
their cars.
Having use one to measure caravan nose weight I think you would struggle, they are not very good! They seem sensitive to load position, also will not
like sideways forces say as you bounce the car to settle. Not to say it will not work, but repeatability problems will probably result.
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yellowcab
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| posted on 10/7/13 at 04:01 PM |
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quote:
Originally posted by sdh2903
I at that point didnt want to own the car anymore because I didnt want to drive it.
I hear you on this one
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sdh2903
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| posted on 10/7/13 at 04:12 PM |
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quote:
Originally posted by yellowcab
quote:
Originally posted by sdh2903
I at that point didnt want to own the car anymore because I didnt want to drive it.
I hear you on this one
When are you booked in. Looking forward to hearing your results
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David Jenkins
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| posted on 10/7/13 at 04:20 PM |
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quote:
Originally posted by Bluemoon
Having use one to measure caravan nose weight I think you would struggle, they are not very good! They seem sensitive to load position, also will not
like sideways forces say as you bounce the car to settle. Not to say it will not work, but repeatability problems will probably result.
As I said earlier - this is more of a thought exercise! 
It's just that the standard answer on here when corner weighing is discussed is "use bathroom scales" and I was just wondering about
their practicality. The alternative to bathroom scales would be to use a spring balance suspended from a beam or engine hoist. Goodness knows how
much a useful one that read up to 200Kg would cost!
The pressure gauge/brake cylinder set-up is much easier to use - when I borrowed one off Rusty Nuts it took barely 10 minutes to get the weights right
on my car.
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yellowcab
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| posted on 10/7/13 at 04:30 PM |
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Booked in for Friday 2nd August
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mark chandler
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| posted on 10/7/13 at 04:42 PM |
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Bathroom scales here, they cost £4.99 and weigh up to 20 stone but as a dial you can overspin to maybe 25kg.
First off I calibrated loaded scales, 4 x 25 litre drums filled with water placed on top of each in turn matched the dials.
Next 4 x concrete flat slabs laid on a small bed of sand, one for each wheel which I levelled to each other.
Place scales on slabs, place car on scales using a jack so I do not upset anything.
I weigh 13 stone ballasted the drivers seat with my body weight
Set the pitch, ride height and balance across thevcar, Blocks of wood 4" for front chassis, 4.5" for rear chassis, much easier than trying
to use a tape.
Ipad for camber and caster using "bubble level" could have just used a spirit level but the ipad fits the wheel rims.
String for toe in, wrapped around the car and tensioned with a bungy.
Took a couple of hours, I also swapped the scales around to confirm accuracy.
Okay it's a bit if a faffing, took a couple of hours with twiddling the spring seats but the only cost was the scales and I am very happy with
the results, it would take a couple of hours to deliver somewhere.
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TimC
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| posted on 10/7/13 at 05:27 PM |
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Dave at Track Developments and Matt and Ivan at Procomp are the only people I'd use for suspension work. I've spent several hundred quid
with Procomp and several thousand with Track Developments over the years. Good people.
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David Jenkins
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| posted on 16/7/13 at 06:01 PM |
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quote:
Originally posted by David Jenkins
I was wondering whether the principle of leverage could be used - take a hefty plank around 600mm long, put one end on a pivot and the other on the
scales, and then put the wheel halfway along the middle (maybe with a block of wood to stop the wheel in the same place every time). I'd guess
that the wheel on the other side would have to be raised to the same amount so that the car was level - just a couple of inches - if only one scales
was in use. If that would work then any cheapo scales would cope.
After all, what's required is a number, not an accurate weight, so as long as the wheels on each side are parked on the same part of the lever
then you would get an indication of whether a wheel's pressure on the ground is higher, lower, or the same as the one on the other side.
(If you follow what I mean... )
Well, I had a go at this!
I managed to find enough bits of scrap angle iron to make a frame 36" long. Pivot at one end, flat plate at the other to go on the scales, and
2 bits of hefty angle iron to take the tyre exactly half-way between pivot and scales. It worked quite well, and I managed to prove that there was
roughly 1Kg difference between the 2 front wheels - which I don't intend to chase just now. The scales showed about 75Kg, which is roughly
mid-range for the scale's 'normal sort of weight to measure'.
I'd show a picture, but some of my welds are too embarrassing to show in public... good enough for this job, but not something I'd want to
display. It's been far too long since I did any significant welding, and it's amazing how quickly you lose the knack... 
Oh - and don't use electronic scales like I did, it's a real faff trying to initialise them before weighing each wheel...
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