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Here is the specifications of the die spring used for the coil spring suspension that was displayed at the builder's meeting at Brampton.


Landing gear die spring specifications
Manufacture: Danly
Type: Heavy Duty
Inside diameter: 1"
Outside diameter: 2"
Length: 10"
Catalog number: 9-3240-26S
Lbs. req’d to deflect 1/10th inch: 51.6
Total deflection recommended for long life: 1032lbs. - 2" deflection
Total deflection recommended for average life: 1290lbs. – 2.50" deflection
Maximum operating deflection: 1548lbs. – 3.00" deflection
Total travel to solid: 1875lbs. – 3.62" deflection
Under normal load, each spring is compressed about 1/2" - 5/8" while the Rebel is just sitting on the ground.
This equates to a long life for the spring before replacement.

Sprung-loaded,
Rick Ford
436R

Hi Rick

Weird numbers. I know your gear works fine and does not sag very much
so something must be amiss with the spring specs or maybe my math.

If I remember correctly, the ballpark numbers were something like spring
force is 1.7 times the weight on the wheel, even at 1 g weren't they?
(The multiplier would increase somewhat as the gear deflects and changes
the geometry) Say 800 lb per wheel at one g giving maybe 1400 lbs on the
spring at 1g. ?? I would have expected a spring that gives maybe 4000 lb
or so force at full compression...

Ken

Rick and Cathy Ford wrote:

Maximum operating deflection: 1548lbs.