Why Micronaut Centaurs Are Unstable

Just WHY are Micronaut Centaurs so unstable?  Is it the Legs, the knees the O rings?  What is it?

I believe I just solved a 35 year old problem.

When I made custom Centaurs I thought the problem was the knees.  Plastic wearing on plastic.  Any substance rubbing against itself will breakdown and become loose.  So I thought that by installing knee rivets I had taken care of the problem.  I tightened them up and then I made a stand.

Now between the rivets and the stand I greatly improved the balance of the figure and made it more rigid as well.  To make it even tighter, I use O rings that are almost half the size of the ones found in 3 3/4" Micronauts.  But it wasnt perfect.  If it was perfect, then I should be able to pose the Centaur in a rearing mode without a stand.  I cant.

Since 06 I have been without a Vintage MEGO Centaurus.  So recently I purchased 2.  One was stated as complete the other was in pieces.  Unfortunately time reacts to plastic pretty much as it does to die cast.  The plastic gets extremely brittle.  When I opened the package both back legs fell apart at the knees.  The extra parts were junk.  Mostly broken pieces that had been glued, so I couldnt use them.  When I finally was finished, I had rivets in 3 knees.  The fourth leg was nice and tight (front) so I didnt want to touch it.  But it doesnt look right with 3 rivets.

But in my messing around with the Centaur, I found the problem.  The true problem with the Centaurus and why it has so much difficulty in holding a standard pose is because it wasnt fully engineered properly for the parts or rather one part in particular. The O ring.

The distance of the underside of the hook in the front legs to the top of the circle that holds the O ring when assembled is roughly 9/16" or .5625".

On the back legs, that same distance is almost half that.  Its slightly smaller  than 9 mm or roughly .340"

They use the same size O ring for both parts of the figure.  The distance is great enough to stretch the O ring and make the front legs tight.  But for the back legs it hardly stretches the O ring at all, allowing the back legs to move on their own instead of holding a pose.  There is no tension on the O ring to keep the back legs tight.

My custom figures were holding a pose better than the factory figures only because I use smaller O rings.  And even then they werent small enough to take up the slack required to make the rear legs function as they were intended.

I was in the process of taking pictures to illustrate this when my camera gave up the ghost for good.  This really sucks.  Because that means it will be about 90 days before I can get a new one.  So no new pictures for a while.  Its been just a terrible 48 hours in my house.  If it aint broke...wait a minute and it will be.  Shit.

I am on afternoons Monday and will see what assortment of O rings we have at work.  If I can find the proper size needed I'll post a diagram of the measurements.