rodgling
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| posted on 20/9/15 at 09:11 PM |
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cheap corner weighting kit
Have just invested in some of these:
150Kg/300kg Heavy Duty Digital Postal Parcel Platform Scales Weigh Post Office
Seems like good value compared to "proper" kit, and should do the job nicely - will report back results.
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loggyboy
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| posted on 20/9/15 at 09:47 PM |
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Shame they dont do a 400kg version as really fancy some for rhe clio.
Mistral Motorsport
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Brian R
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| posted on 20/9/15 at 10:27 PM |
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The exact same ones we use. They're fine. Not as robust as the real sets but more than up to the job for a seven type car.
Make a set of blocks up the same height to roll the car off the pads whilst suspension fiddling/jacking up etc.
Stock up on spare batteries too. ;-) You'll go to use them after a while and they'll be flat!
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Daddylonglegs
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| posted on 21/9/15 at 08:23 AM |
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They certainly look like a great alternative 
As for the batteries going flat, there seem to be more and more gadgets on the market that drain battery life even when not being used. I've
found the best thing is to just pop a piece of card in between one end of a battery and the contact to stop that happening. As the scales won't
be used that often (I would guess) then it's no big deal to just remove the card when you need to use them.
Just my 2p worth
It looks like the Midget is winning at the moment......
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dij
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| posted on 21/9/15 at 08:34 AM |
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I have the same ones, they are a little tall but do the job well enough.
It does help if you have a measured weight to set the "tare" on them before use (zeroing)
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Toys2
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| posted on 21/9/15 at 10:04 AM |
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Assume that I know nothing about checking corners weights 
Do you have 1 set of scales and move them around or need 4 sets?
If using 1 set, would you then have 3 blocks to sit the other wheels on?
Thanks
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dij
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| posted on 21/9/15 at 10:06 AM |
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You usually use 4 sets
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AlexXtreme
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| posted on 21/9/15 at 04:07 PM |
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would't one be enough and move it round between wheels?
If necessary rest the other wheels on wooden blocks of the same height to keep the car level
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Lander
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| posted on 21/9/15 at 05:19 PM |
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In theory you could use one and blocks the same height but it will take so much longer, changing one corner can easily affect the other 3 too.
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AlexXtreme
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| posted on 21/9/15 at 06:50 PM |
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if the heights are the same then how can the weight change...? agreed it will take longer however I cant see myself checking the weights very often
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Lander
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| posted on 21/9/15 at 07:46 PM |
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If you adjust one corner it can alter the other 3 slightly. Your idea will work to get it roughly right.
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Toys2
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| posted on 21/9/15 at 09:29 PM |
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Thanks for the responses, after writing it, I did wonder if moving the car during set up wouldn't be the best idea
Though I suppose if you had 1 scale and 7 blanks, it could work without too much trouble....
The car on the scale and 3 blanks, then roll the car onto the 4 other blanks, swap the scales and roll it back
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killerferret666
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| posted on 22/9/15 at 09:48 AM |
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At the IVA one of the scales was broken so he only weighted each corner a time but had it on both scales.
I think the difference would be very small if done on a per axle basis. It would definitely give you a good guide and if you weighted it the same way
for future weighing (if stripping weight) that would give you an accurate difference in weight.
Building DDR GT4
Miami Gt4 Blog - Click Here
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Ugg10
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| posted on 22/9/15 at 11:35 AM |
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quote:
Originally posted by killerferret666
At the IVA one of the scales was broken so he only weighted each corner a time but had it on both scales.
I think the difference would be very small if done on a per axle basis. It would definitely give you a good guide and if you weighted it the same way
for future weighing (if stripping weight) that would give you an accurate difference in weight.
I think for getting all up weight the 1 scale/3 block approach would be fine. But for setting up corner weights every time you change one corner all
four should be checked and therefore having to move the scale round all four corners each time you turn a suspension platform would be a right PIA.
---------------------------------------------------------------
1968 Ford Anglia 105e, 1.7 Zetec SE, Mk2 Escort Workd Cup front end, 5 link rear
Build Blog - http://Anglia1968.weebly.com
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Edwardo
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| posted on 23/9/15 at 06:55 PM |
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Just wanted to say thanks for the link rodgling 
I bought a pair of these after reading your post, they arrived tonight and seem to be brilliant value for money so have just ordered the other 2.
Many thanks again
Tony
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hornetV2
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| posted on 2/10/15 at 01:36 PM |
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Looks like a good Locost alternative
I no longer have access to a set of Intercomp scales, so these would be very handy. The Intercomp scales used to weigh a lot and so were difficult to
transport around. These look to be much lighter, so could anyone let me know how heavy they are?
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Edwardo
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| posted on 2/10/15 at 01:40 PM |
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I can get the exact weight when I get home for you if you like. But if you’re just looking for a rough idea they are easily as light as my bathroom
scales.
Cheers
Tony
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hornetV2
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| posted on 2/10/15 at 02:06 PM |
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Hi Tony
No need for the exact weight, your approximation is fine
Each Intercomp scale used to make me grunt when I lifted it, so these will be a fraction of the weight.
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Fandango
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| posted on 5/10/15 at 07:18 PM |
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Think I will invest in a set of these.
In the meantime I have a set of (very expensive) ones on loan.
Can anyone point me to an online tutorial for setting corner weights. I am just about to do my first trackday, and have (with an 85kg driver);
LF144
RF125
LR147
RR166
With no driver I have;
LF144
RF105
LR123
RR126
Total weight of 498,so happy enough with that.
"I hate to advocate drugs, alcohol, violence, or insanity to anyone, but they've always worked for me." Hunter S Thompson
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hornetV2
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| posted on 6/10/15 at 07:00 AM |
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People can go on for ages about how to corner-weight a car but for general circuit work in a car that is not symmetrical (like a single seater) the
idea is to get the diagonal totals to equalise within a few Kg of each other. This way you maximise the grip (and get the car to feel the same)
during the transient changes (turn-in to a corner and accelerating out of a corner).
I assume you want the best from the car with just yourself in it and your current diagonal totals are:
LF + RR = 310kg
RF + LR = 272kg
As you can see your diagonal totals differ by 32kg, which is too much.
Think of yourself sitting on a four legged bar stool and one of the legs is shorter than the other three, so if you shift your weight diagonally the
chair will rock along the diagonal with the shorter leg (and you will spill your beer), and nothing will happen the other way. So using this analogy
you now need to vary what weight the suspension is seeing on your car, so either push the RF and LR further into the ground by raising the spring
platforms, or reduce the load on the LF and RR by winding the spring platforms down.
IMPORTANT - YOU ARE NOT SHIFTING WEIGHT AROUND THE CHASSIS, ONLY CHANGING WHAT THE SUSPENSION IS REACTING AGAINST
Another thing to bear in mind is to ensure any anti-roll bars are disconnected prior to doing any measurements and soften any adjustable dampers.
When reconnecting the anti-roll bars, do it at the preferred weight of the car (driver sat in) and ensure the drop links are adjusted so the bolts
just slide in.
To answer earlier questions, having four scales makes this a relatively simple process, having just one and three blocks can make it a days work!
The above is just a simple guide to a very complex subject, so you may need some pop-corn for the debate this may kick off!
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hkp57
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| posted on 6/10/15 at 07:57 AM |
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Good web page here
https://robrobinette.com/corner_weight_calc.htm
Fleet
SKC Raptor R - Hayabusa
Toyota C-HR Hybrid Limited Edition
Honda VFR1200 CrossTourer
DCT
Marlin Roadster 1800
Mercedes Vito 116 Sport
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Fandango
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| posted on 6/10/15 at 11:56 AM |
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quote:
Originally posted by hornetV2
People can go on for ages about how to corner-weight a car but for general circuit work in a car that is not symmetrical (like a single seater) the
idea is to get the diagonal totals to equalise within a few Kg of each other. This way you maximise the grip (and get the car to feel the same)
during the transient changes (turn-in to a corner and accelerating out of a corner).
I assume you want the best from the car with just yourself in it and your current diagonal totals are:
LF + RR = 310kg
RF + LR = 272kg
As you can see your diagonal totals differ by 32kg, which is too much.
Think of yourself sitting on a four legged bar stool and one of the legs is shorter than the other three, so if you shift your weight diagonally the
chair will rock along the diagonal with the shorter leg (and you will spill your beer), and nothing will happen the other way. So using this analogy
you now need to vary what weight the suspension is seeing on your car, so either push the RF and LR further into the ground by raising the spring
platforms, or reduce the load on the LF and RR by winding the spring platforms down.
IMPORTANT - YOU ARE NOT SHIFTING WEIGHT AROUND THE CHASSIS, ONLY CHANGING WHAT THE SUSPENSION IS REACTING AGAINST
Another thing to bear in mind is to ensure any anti-roll bars are disconnected prior to doing any measurements and soften any adjustable dampers.
When reconnecting the anti-roll bars, do it at the preferred weight of the car (driver sat in) and ensure the drop links are adjusted so the bolts
just slide in.
To answer earlier questions, having four scales makes this a relatively simple process, having just one and three blocks can make it a days work!
The above is just a simple guide to a very complex subject, so you may need some pop-corn for the debate this may kick off!
Many thanks for your excellent input. Could be a busy day at Oulton Park for us, next week!
"I hate to advocate drugs, alcohol, violence, or insanity to anyone, but they've always worked for me." Hunter S Thompson
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johnH20
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| posted on 6/10/15 at 05:12 PM |
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Anyone tried these scales out yet? Mine arrived this morning and I could not resist having a go. I have some slightly disturbing results:
- My two scales are 3 kg different when weighing me - approx. 80 kg.
- One of the scales initially produced some erratic results including residual readings of up to 54 kg when a 200 kg load was removed ! After
excercising the scale some 10 times it seemed to stabilise with a net figure of 1 kg after load removal.
- When compared to my previous weighings using multiple mechanical bathroom scales the results were:
Front Rear Total
- Bathroom scales 230 385 615
- New electronic scales 219 373 592
- Norwich IVA 230 400 630
I have no idea which is right in absolute terms. My readings are all an average of 5 at each wheel taken as pairs. The IVA readings were made outside
as a one off and the reading seemed to flicker with the state of the breeze. I am sure my weighing technique can be improved as I did not take
excessive care over levelling but my data sets are consistent within themselves.
So my car ( fully tanked ready to go ) weighs somewhere between 592 and 630 kg . Take your pick!
I need to take more measurements but I have a suspicion that the 'dodgy' scale may have a non linear characteristic at the higher loads
relative to the other in which case I will send it back. So the warning is take care when using this bargin equipment!
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johnH20
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| posted on 6/10/15 at 05:54 PM |
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As an aside why does my carefully formatted post get centred in this way! Is it me or Fozzie ?
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rodgling
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| posted on 6/10/15 at 07:34 PM |
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Just tried mine with a weight of around 23 kg. Two read 21.7, two read 22.7, not great (about 4.4% different).
Anyone know how to access the calibration function? The high quality manual suggests holding down the Mode button but this doesn't work for me?
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