Random stopping objects

[GoogleCodeExporter]

What steps will reproduce the problem?
1.  make a basic car (rectangle with cylinders...)
2. add joints to make wheels move - add 10 acceleration to joint (or any value)
3. click play

What is the expected output? What do you see instead?

Object moves forward, then stops. 
What version of the product are you using? On what operating system?
Sketchup version 6
Windows Vista Ultimate 64-bit

Please provide any additional information below.
I make a car to go down a track with some jumps and such, I have the joints 
accelerate at 10.
I press play, car moves forward, then stops.
no mater what i do, the object always stops at a certain point.
I can make a piston, and it works fine because its stationary, but as soon as i 
want to make 
something fall down a ramp or move in a direction, it stops.

Original issue reported on code.google.com by hayden_s...@mac.com on 30 Nov 2008 at 12:47

[GoogleCodeExporter]

What is the maximum angle for the joint set to? If you want the joint to be a 
motor
that rotates indefinitely, then you'll need to set the maximum angle to a very 
high
value (say, for example, 1000000), so that the motor will not stop rotating. If 
it's
set to 360, for example, then the motor will make one complete revolution and 
then stop.

Original comment by javawiza...@gtempaccount.com on 25 Jan 2009 at 9:15

[GoogleCodeExporter]

no, its not the joint itself stopping, its the whole object. I had no idea that 
you have to make the system really 
small so that it actually moves, apparently sketch-up limits how far down a 
given path the object can move.

Original comment by hayden_s...@mac.com on 25 Jan 2009 at 9:10