 Checking spring rate, Am I doing it right? |
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| bondo |
 Jan 8 2006, 09:17 PM
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#1
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Practicing my perpendicular parking  Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California  |
I set the spring with a metal plate on it next to a wall. I made a mark on the wall at the top of the plate. I added 25 lbs, 50 lbs, and 230 lbs (me), and marked the wall accordingly. I then did the math to calculate pounds per inch, and I get around 120 lbs per inch. (for example, it deflected 1.9 inches when I stood on it)
All the measurements started with a nearly completely unloaded spring, which is not the situation it will see in a car. Is the spring effect linear, or do I need to install them in a 914 and see how much it dips when I jump in the rear trunk? |
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| Borderline |
Jan 9 2006, 10:09 AM
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#2
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Senior Member Group: Members Posts: 720 Joined: 8-February 05 From: San Juan Bautista, CA Member No.: 3,577 Region Association: Northern California |
That's the principle. You should be in the ball park. Make sure the spring is linear...All the coil spacing is the same distance when unloaded. I have a set of springs with 3 coils that are wound very close and actually go solid when installed in the car. That changes the rate. I think they did that so the spring wouldn't fall loose when the car was jacked up as it often is. Good luck. (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)
Bill |
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Posts in this topic
bondo Checking spring rate Jan 8 2006, 09:17 PM
SirAndy Jan 8 2006, 10:38 PM bondo http://www.914world.com/bbs2/ht... Jan 9 2006, 10:00 AM bondo ... Jan 9 2006, 11:01 AM ppickerell Aaron is right. Get the spring under some load at ... Jan 9 2006, 11:29 AM bondo Jan 9 2006, 12:09 PM ppickerell Ooops, My bad, the springs I make are so f'in ... Jan 9 2006, 12:27 PM bondo Ok, I tried it with more weight. I added weight in... Jan 17 2006, 04:17 PM Mueller Jan 17 2006, 04:31 PM bondo <... Jan 17 2006, 04:53 PM Mueller Jan 17 2006, 04:57 PM bondo <... Jan 17 2006, 05:29 PM bondo I think I may have figured out where the 1/4" come... Jan 17 2006, 06:59 PM bondo Ok, here's the pic.. this is 300 lbs. Half the... Jan 17 2006, 07:28 PM bondo Ok, I measured the spring and used this formula to... Jan 20 2006, 06:19 PM
bondo Here is the graph of the data. (I did the graph a ... Jan 20 2006, 06:22 PM |
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