can anyone tell me what this thing is really really used for?

There is no pointer and no bubble. The level reference is a neighbor's driveway when sighting over the wheel. I suspended the wheel at its 3- dimensional center of gravity, empirically determined, then moved the suspension point about half a millimeter upward by backing out the

It does.

Exactly. The wheel is statically balanced but it wobbles when turned. I think a normal bubble balancer won't allow the wheel to wobble as it spins. The tradeoff is extremely high maintenance on mine.

I model this as a thin disk weight on a pendulum. The bubble shows if the pendulum rod is vertical. Static unbalance tilts the pendulum.

A dynamically unbalanced tire on a static balancer cone equals the disk tilted at an angle but welded to the pendulum rod. At rest, the pendulum rod is still vertical. If you spin the disk it tries to flatten out, which tries to make the pendulum rod's suspension point move in a circle. Maybe the idea of the long stem on the static balancer is to allow this??

Mine works by having a -very- short pendulum rod that lets the rotating disk flatten out easily.

Jim Wilkins

I'd have to see this thing at work but it sounds as if you might have made yourself a dynamic balancer. Your model doesn't help me but I may just be visualizing it wrong.

In any case, once you understand the principle you know what's going on. That's the most important thing.

-- Ed Huntress

I still have one of the old spark style dynamic units someplace buried in the shop. Haven't used it in years though. Not sure if it even works any more.

Oh and ED I misread your post. Sorry. However it is possible to balance a tire statically and eliminate any tire wobble. It takes a lot of practice at reading the tire and knowing your equipment. That takes time and effort. Both of which are in short supply in the tire chain shops. Most of the boys I see in those places have a hard time setting the air pressure!

Jim Wilkins

No way, Jose. I used to bust-n-balance tires as part of my job and a crappy dynamic balancer beat a good bubble balancer any day.

You need some spelling lessons, too.

-Carl

"Carl Byrns" wrote: (clip) You need some spelling lessons, too. ^^^^^^^^^^^^^^^^^^ Spelling error(s) in the following quote? "Static balancers do as good a job as the new dynamic units, but they are

"Leo Lichtman" wrote: I couldn't find any, not could my specc check. ^^^^^^^^^^^^^^^^^^ I sould have used Spell Check on my own post.

A running gag with Karl and myself.

-Carl (not part of the secret Carl conspiracy)

No, it is not. A bubble balancer can only tell where a wheel is heavy/light across the diameter, it treats the wheel like a two-dimensional disk. A dynamic balancer treats the wheel like a cylinder and can find the heavy/light areas in three dimensions.

-Carl

Now this is fummy!

"Ronald Thompson" wrote: Now this is fummy! ^^^^^^^^^^^^^^^^^^ I wasn't trying to be fussy.

I figured. That made all the more funny. Sorry.