45 replies to this topic

[hanra]

Yep, gotta pull the needle off the speedo. I put the white LH ones on mine. I was able to re-calibrate the speedo at work when I re fitted the needle. I would be cautious about painting the needles as the extra weight may effect accuracy.

[hanra]

[ls2lxhatch]

I doubt the weight or paint would have a measurable effect on accuracy.

Is the speedo needle on the factory gauge balanced?

When I pulled the needles off my electronic VDO gauges I found that only the tacho needle was balanced, presumably because it moves quickly. As the speedo needle is not balanced I don't think paint would have any effect on the accuracy of an electronic speedo. If the mechanical speedo needle is not balanced then I think the same would hold true for a mechanical speedo.

[hanra]

Unsure about balancing. However the speedo relies on magnetism to move the needle and the clock spring resists this force thus (hopefully) giving us an accurate reading. The clock spring is quite fine, so I would assume any change in weight could effect its readings? Perhaps this could be minimized during the final calibration I don't know?

Edited by hanra, 10 June 2012 - 07:49 PM.

[ls2lxhatch]

If the needle doesn't have a balancing weight then the weight of the needle will vary depending on its position. An unbalanced needle will exert more weight on the spring when it is horizontal than it would when vertical. A balanced needle would have no effect regardless of whether it is horizontal or vertical.

If the needle is balanced there would be a lead weight opposite the pointer.

I suspect the weight of the needle is insignificant compared to the spring pressure.

Edited by ls2lxhatch, 10 June 2012 - 08:10 PM.

[hanra]

As I've never seen the needles in operation fitted to a car, at night time, do the needles glow with the lighting?

[S pack]

If the needle doesn't have a balancing weight then the weight of the needle will vary depending on its position. An unbalanced needle will exert more weight on the spring when it is horizontal than it would when vertical. A balanced needle would have no effect regardless of whether it is horizontal or vertical.

If the needle is balanced there would be a lead weight opposite the pointer.

I suspect the weight of the needle is insignificant compared to the spring pressure.

The wieight of a needle doesn't even register on our electronic Kitchen scales (reading is 0 grams). A coat of paint on the needles will make no registerable difference to the instruments readings, these are automotive instruments not precision aircraft instruments.

[A9X]

Gentlemen, i think we have achieved a new high ( or low ) in the rivetcounting stakes.

[hanra]

Ah well, Ill keep my mouth shut and go back to repairing Aircraft Instruments and Avionics.

Or if I cant fix it...chop it daddy!!!

Edited by hanra, 11 June 2012 - 07:52 PM.

[tuxedoss]

Many years ago I painted my lx needles, just a single coat of model paint with a fine brush. The only gauge that was affected was the tachometer, even with just a thin coat te needle became very slow and lazy and didn't read correctly, I wiped the paint off and it was perfect again.

[hanra]

Are the instrument lamps green from factory??

[AbsynthHatch]

I don't think its intensionally mean't to be green as your probably imagining

Though it is the best colour discription of most old Holdens' dash lighting colour

Its certainly nothing like newish type cars and even your Mini would have a clearer type incandescent glow to its guage/speedo cluster

[hanra]

Ok cool. I just thought perhaps the instrument lamps were meant to have green condoms over them? The lamps I've fitted are all plain.

[A9X]

not having a shot at you or Andy, Brad. Love the effort you are putting in and visit the thread every time you update. i appreciate Andy's depth of knowledge always.

Just an observation is all.

[hanra]

Hey nah your right mate!! I don't take much personally. I know most of the stuff i come out with isn't really exciting stuff. I just like things to work as they were designed to. As Tuxedoss commented though, his personal experience was the paint did effect his tacho needle. I was just commenting from my experiences from my line of work. All good bud.

[ls2lxhatch]

Ok cool. I just thought perhaps the instrument lamps were meant to have green condoms over them? The lamps I've fitted are all plain.

The LH SL/R dash I have has blue lenses fitted inside for the four dash lights. The speedo is the white needle 0-200 km/h only with a single slot for the odometer.

[hanra]

Ah yes.. Been some months since I had my cluster in bits. Thanks for that one!

[ls2lxhatch]

I think the green look may come from the old clear globes giving off a yellowish light through the blue lense.

The SL clusters I have pulled apart do not have the blue lenses.

[AbsynthHatch]

Aahh yes the blue bulb holders, I stand corrected, interesting with regards to the SL not having them

The instrument lighting has always been abit on the dullish side, as suggested an LED style bulb sounds interesting

It would be nice to brighten it up a little without taking away the factory appearence

[hanra]

Some times I've found LED lamps just don't have the light spread of an incandescent lamp. They tend to focus the light in one direction more so. Perhaps a good experiment for someone?

I had actually fitted LEDs to the tail/brake and indicator lamps in my other car. But I swapped back to incandescent, the LEDs didn't seem to light the entire lens up as well as the incandescent.