Measuring coil bind question
#1
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Measuring coil bind question
I got a new benchtop spring tester, and decided to do some prep measuring on the PAC 1518 springs I have, so the first thing I wanted to measure was coil bind.
Before I began, I figured I'd just crank them down till I can't crank anymore and coil bind would be pretty obvious to see. Problem with this is I could have kept cranking past the 600-lb rating on the gauge.
Then I decided to go for "visual" coil bind, so I cranked them down until it visually looked like the coils were coming into contact. I tried getting feeler gauges inside, used a flashlight and magnifying glass to try to get to the exact point where the springs would touch, because I figured if the coils were touching, that was as close as I would want them anyways.
I think the differences between my two methods was 0.035" in some cases. And from my "visual" coil bind measurements, I'm probably going to shim the springs to .050-.060" from "visual" coilbind of 1.080".
Does this seem about right? For those of you who have measured coilbind before how far are you compressing the springs?
Before I began, I figured I'd just crank them down till I can't crank anymore and coil bind would be pretty obvious to see. Problem with this is I could have kept cranking past the 600-lb rating on the gauge.
Then I decided to go for "visual" coil bind, so I cranked them down until it visually looked like the coils were coming into contact. I tried getting feeler gauges inside, used a flashlight and magnifying glass to try to get to the exact point where the springs would touch, because I figured if the coils were touching, that was as close as I would want them anyways.
I think the differences between my two methods was 0.035" in some cases. And from my "visual" coil bind measurements, I'm probably going to shim the springs to .050-.060" from "visual" coilbind of 1.080".
Does this seem about right? For those of you who have measured coilbind before how far are you compressing the springs?
#2
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I always compressed the springs until I could feel a noticeable spike in the amount of effort to compress the spring any more, and that's where I stopped. You should be able to feel it when you hit this "wall". I wouldn't keep cranking on the wheel as hard as I could, but it was a little further than "visual" coildbind.
If you're not sure, it's probably better to err on the larger coilbind measurement. The consequences are a lot worse if you're too tight versus too loose.
If you're not sure, it's probably better to err on the larger coilbind measurement. The consequences are a lot worse if you're too tight versus too loose.
#3
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You can compare PAC's coil-bind rating (1.080") to what you're seeing and you start to get a feel for it. You will also see the bottom piece of the scale start to move downward if you over-crank it, and that is obviously too far.
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More than likely I will set everything up with a 1.080 theoretical coil bind and shim accordingly.
#6
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The LSM 600lb tester, it's a horizontal mount one. And the box says 1.140" but the website says 1.080". I may have gotten an older batch, which annoys me somewhat, but that's why I decided to test...that, and I'm over precise on a lot of things I build.
More than likely I will set everything up with a 1.080 theoretical coil bind and shim accordingly.
More than likely I will set everything up with a 1.080 theoretical coil bind and shim accordingly.
Yep and just do the math and you'll be damn close...
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I took my springs to a local engine builder he put them on a machine that measures the spring forces from open to coil bind and provides a printout. Worked out very well for figuring shims needs and open closed figures. He charged me like 25 bucks.