O-Ring Cleaning (pre-flight)

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Well-Known Member
Jan 25, 2009
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Hi all,

I was reading some of the great information on the Dr. Rocket site. I came upon this quote:

There might also be a tiny speck of dirt on the o-ring that the user didn't see.

They are referring to failure modes common to their motors. This brings me to my question. Are there any ways to clean an O-ring before flight to insure that it is clean to further reduce this sort of failure mode (blow-by?)?

I have never cleaned the rings perse, except maybe after I dropped one in the dirt. Of course my Aerocon o-ring luber does do a bit of scrubbing.

The skeptical side of me wonders if this is grasping to explain why blow-bys are the fault of the user. I haven't fully read a set of reload instructions in a while. If this is really a factor I'd expect the statement to be there too.

Despite my skepticism, from now on I will try to remember to check them just prior to lubing.
Don't remove your o-rings from the package until you are ready to assembly the motor.

Assemble the motor on a clean table.

Don't grease anything until you are ready to assemble the motor.

The o-rings usually won't attract dirt until greased. Assembly on a clean surface with minimum lubrication will prevent o-ring contamination.

Aerocon makes a great o-ring lubricaor that applies the minimum amount of lube.



Also don't get distracted when assembling a reload.

Bob Krech
I realize those steps, Bob, thank you. What I am talking about is if a klutzy person like most of us have been at one time or another drops a greased O-Ring on to the ground, gets it covered in dirt. Is there a way to clean that off? Maybe wash it, dry it, then grease it again, hoping not to drop it?

A clean baby wipe should do the trick. I've been lucky enough to only drop ungreased o-rings (looking for wood to knock on).