need to check coil springs
- Thread starter vosevichs
- Start date
Gettin Dizzy
Rational Racing
Ok, here is how I check spring rates.
You need to have, a press, one scale pad, and fitting of some sort to go on the ram of the press (I used a big seal driver, large enough to cover the diameter of the spring). This last is used to keep the spring from flying out of the press under compression. And a digital caliper big enough to check free height of spring or if you checking something like a 14" coilover spring, just use a a tape measure to check free height, and remember it, write it down in your set-up book, and if it ever falls more than 2% of it's free length, pitch it. All springs "set", this is why you keep track of free height.
First set the scale pad on the press, put the spring in under the ram, run the press down till it just makes contact with the spring, measure it (you don't have to zero the scale pad yet) compress the spring one inch (you can just go 1/2" for conventional front springs (ie; modified front) so you don't kill your scales) now zero the scales, compress one inch and read the scales. That's your spring rate. Just remember, if you are running a gas pressure shock to check the rate on them as well, and add the rate to the spring rate. (check them the same way). If you want to check a progressive spring rate, things are a lot harder, but not impossible, graph paper makes it easier to "see" the rate. you just have to make a lot more masurements. Remember, rate is only how much force an inch of compression is.
Hope this helps somebody, I had to learn it on my own.
You need to have, a press, one scale pad, and fitting of some sort to go on the ram of the press (I used a big seal driver, large enough to cover the diameter of the spring). This last is used to keep the spring from flying out of the press under compression. And a digital caliper big enough to check free height of spring or if you checking something like a 14" coilover spring, just use a a tape measure to check free height, and remember it, write it down in your set-up book, and if it ever falls more than 2% of it's free length, pitch it. All springs "set", this is why you keep track of free height.
First set the scale pad on the press, put the spring in under the ram, run the press down till it just makes contact with the spring, measure it (you don't have to zero the scale pad yet) compress the spring one inch (you can just go 1/2" for conventional front springs (ie; modified front) so you don't kill your scales) now zero the scales, compress one inch and read the scales. That's your spring rate. Just remember, if you are running a gas pressure shock to check the rate on them as well, and add the rate to the spring rate. (check them the same way). If you want to check a progressive spring rate, things are a lot harder, but not impossible, graph paper makes it easier to "see" the rate. you just have to make a lot more masurements. Remember, rate is only how much force an inch of compression is.
Hope this helps somebody, I had to learn it on my own.
