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From:  Sky2high [at] aol.com >INTERNET:Sky2high [at] aol.com

Subj:  Main Gear Actuator Bottom Out



Ed,



I still don't know what condition got the pushrod a bit out of line --

pivot

resistance, wind buffet just before pressure was re-applied, special load

from

a hard landing, side landing, too fast of a turn, etc, etc, etc, but it did

not come into contact with the overcenter link wing attach point -- close,

but

no contact.



Consider this:  Did you ever tow your tractor out of spring mud utilizing a

long chain between the tractor and a far away tree and by pulling

perpendicularly at the center?  Pulling a few feet moves the tractor a few

inches.  This is a great multiplier of power and works just as well in

reverse

if the middle is slightly bent.  Nails go in quite straight until they are

hit

a bit obliquely - then they easily bend.



If one assumes something caused the slightest misalignment and the physical

ends of the cylinder and push rod are contrained, the remaining 1/4 inch

push

could cause quite a bend.  Considering the unreliability of the 2nd

generation

pressure switches, the push may have been at max pump pressure.

Furthermore,

I was able to straighten the push rod by unbending it against my knee (of

course, these were first generation actuators).



In any event, bottomed out push rods can't be pushed any further -- Ergo,

they

can't be bent by irrestible forces applied against immoveable objects.



Scott Krueger

N92EX