Kismet Turning Radius Gauges

[akstsstjs]

I have recently acquired these.
No instructions, but I have read up on the internet and understand how to use generic ones.
I was expecting the locking pins to lock the turntables in position at zero degrees.
They don't.
They only lock the front to back, sliding horizontal movement of the upper half of the gauges including the turntables, not the turntables themselves.
Are they meant to lock the turntables and are broken?
Am I missing a hidden feature that will lock the turntables?
Were the gauges designed without a lock for the turntables? If, so I don't see how they can work?
Does anyone have personal experience of using these gauges?
Does anyone have a set of Instructions for these gauges?
Any help is much appreciated.

[GreenV8S]

I'm not familiar with that type of gauge and don't have a manual for it, but it seems to me they're oriented wrongly in that picture. The handles and dials should be facing outwards so the gauge can be read with the wheel on it. Maybe the fore/aft travel you mention is actually sideways travel. That would enable the gauges to shift sideways as the vehicle drives onto it to allow for bump induced track changes or the effects of large toe-in angles. The gauge could be used without being locked if it was designed for two-person use or there was some other way to hold the steering angle.

[akstsstjs]

Excellent feedback thanks.
The sideways orientation, sideways sliding motion and sideways locking pins all makes perfect sense.
That just leaves the apparent lack of a locking mechanism for the turntables.

[E-bmw]

Not sure why you are wanting to lock the turntables.

Isn't it the turning of the turntables that gives the reading for alignment?

[akstsstjs]

Looking at other brands they all seem to have locking pins to lock the turntables and keep them in place at zero degrees whilst you drive onto them.
The locking pins are then removed so the turntables can be used and rotated.

[GreenV8S]

The locking pins are usually there to hold the steering in position while the operator compares the two gauges. Without any way to hold the steering in place, it will tend to return to center on some cars. Contact patch friction would usually prevent this, but these plates eliminate that.