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  #1  
Old 26-01-18, 19:15
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firepete999 firepete999 is offline
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testing springs

i have some springs i would like to double check for rates.

i have a hydraulic press but piston is 1.1/4 " so quessing i need to adjust the pressure measure measurement by some factor .
after compressing the spring by 1"

will i get a reasonable result or am i wasting my time .
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Old 26-01-18, 19:42
No Imagination No Imagination is offline
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Accurate scales, piece of timber, your press, measure reading when spring depressed 1".............I think!
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Old 26-01-18, 20:46
gixxerthou gixxerthou is offline
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I get very accurate (only a few% error repeating the full travel of measurement 5 times), with a press, a balance pad (Longacre in this case) and a steel rule.
Free length, push 1/2", record the weight, push another 1/2", etc...

That accuracy is pretty constant over a wide spring range.
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  #4  
Old 26-01-18, 21:05
Darvie Darvie is offline
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How did you get permission to have the press in the lounge room?.
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Old 26-01-18, 21:08
asklepios asklepios is offline
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Out of interest what was the scatter of results over your 5 measurement? How did your measured numbers compare to the engraved target rate?
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  #6  
Old 26-01-18, 22:37
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firepete999 firepete999 is offline
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i was hoping to just read off top pressure gauge . i believe if the piston was 1" it would be correct scale
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  #7  
Old 27-01-18, 00:00
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Nick Skidmore Nick Skidmore is offline
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Quote:
Originally Posted by firepete999 View Post
i was hoping to just read off top pressure gauge . i believe if the piston was 1" it would be correct scale
It is if area is 1 square inch. A 1" dia piston is less than that. It might be my questionable maths but I think a piston needs to be 1.128" dia to be 1 sq inch.

If that is true and the pressure is reduced on a larger piston - 1.250" dia for example, (1.227 sq ") then the reading needs multiplying by 1.227 / 1.128 =1.088 to give lbs per inch of spring - all that could be complete bollocks of course!
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  #8  
Old 27-01-18, 09:21
St Eval St Eval is offline
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Quote:
Originally Posted by Darvie View Post
How did you get permission to have the press in the lounge room?.
If you knew Graham, that is not at all surprising.
Roy
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  #9  
Old 27-01-18, 15:28
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AndyBougourd AndyBougourd is offline
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this is good

http://www.therangerstation.com/tech...ringrate.shtml

use a vernier
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  #10  
Old 27-01-18, 17:29
AshM AshM is offline
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How accurate is the pressure gauge ?
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