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karg10
10-17-2014, 01:38 PM
Anyone know how to check spring rates using one of your corner scales and a press??? I'm sure someone has figured it out before me!

DirtRacer9x
10-17-2014, 02:47 PM
Put spring on scale. Zero scale. Measure free height. Collapse one inch check scale number. Check up to 3-4" is what I've done.

BigBlueFord
10-17-2014, 04:34 PM
I pretty much agree with DirtRacer9x, except I would suggest preloading the spring about an inch before starting to measure in 1 inch increments. Also be very careful. That loaded spring can do some real damage if it kicks out at you.

hammond motorsports
10-17-2014, 05:34 PM
what I have done is make a spring seat to fit in the press .You will need that for the front spring and after you get set up zero scale . then preload 100 lbs the re zero scale and then move spring 1 inch . that will be very close . I have checked that with my spring dyno also . dyno just gives you more info and does it at 6 inches per second giving you a better rate but the press works just fine takes longer to do .

Lizardracing
10-17-2014, 10:47 PM
Make sure your reloading the same as the manufacture. Some will rate at 1/4 and some will do an inch and others might average four inches. This only applies of you comparing the number on the spring

DirtRacer9x
10-17-2014, 10:49 PM
what I have done is make a spring seat to fit in the press .You will need that for the front spring and after you get set up zero scale . then preload 100 lbs the re zero scale and then move spring 1 inch . that will be very close . I have checked that with my spring dyno also . dyno just gives you more info and does it at 6 inches per second giving you a better rate but the press works just fine takes longer to do .I see what you're trying to do by compressing it at first a little but shouldn't you be checking the rate from non compressed spring to find its true "average" lbs per inch? I know most springs on these cars are compressed when sitting statically and not fully unloaded so I see why you're rating the way you state you are. Just curious as to what you've found doing it both ways since I have not. Thanks.

rsawyers9
10-18-2014, 08:22 AM
I work for an offroad suspension parts manufacturer. When we get sample coil springs, we test them by putting them on the vehicle first and measuring the collapsed spring at ride height to determine the correct testing range. We then load the spring to that same height to get the static load on the spring at ride height. We compress and decompress 2" both ways in 1" increments to determine rate. We use a Tinius Olson load cell for our measurements. This process takes a little longer since you have to first install the spring, but it is very repeatable.

Krooser
10-19-2014, 01:15 PM
Before we had access to fancy spring raters we used to simply set a spring on the ground, measure the free height then load enough lead on the spring to get it to compress one inch. Weigh the lead and that was the spring rate. Crude but it's all we had.