Instrument lens cracks with Speed Hut gauges

[aviationfred]

A few weeks ago, I posted a photo of my instruments and it showed severe cracking near the speedometer and fuel gauges.

With the Speed Hut gauges installed, the lower side of the lens is not able to sit completely closed. I have installed a NEW lens and used some high density foam to add a bit of vibration absorption and to allow no contact between the gauge B ezels and the lens. I am hoping this is a good solution, but it may take a few years and many thousands of miles to determine the effects of this.
In the photo, you can see the screw and threads. I will be looking for a foam or rubber stand-off/bushing to put in there to reduce any side load that the screw may be placing on the clear lens mount ear.

On a side note, the cracked/crazed lens was the original 25 year old lens.

Fred

[RPM - Robert]

Fred, how did you account for the added height of the foam. The black "outer" cover was already pushing against the speedo lens from the factory. Adding that extra material seems like it would be pushing on something else. Possibly cracking the "outer" cover, at the very least breaking off the mounting tabs.

[fj-f3a]

Fred, I encountered this problem when I was installing my Speed Hut Electric Speedo.
My solution was to turn up a flanged bush from some 6061 aluminium.
This bush has an approx .025mm (.001") interference fit with the ID of the gauge, a Flange Width of approx 6mm and a depth equal to the length of the original plastic spacer supplied with the gauge.
With the supplied lens removed, I carefully pushed the bush into the gauge, being carefull not to rotate the dial so as not to loose registration.
The gauge was then fitted through the hole in the instrument cluster and the modified gauge nut installed, not too tight, to hold the gauge in position.
The Bezel thread and the flange on the new bush support the gauge on the instrument cluster base.
The flange thickness was only 1.5mm (.060"). The instrument cover will then screw down as normal.

[ribbert]

Fred, I encountered this problem when I was installing my Speed Hut Electric Speedo.
My solution was to turn up a flanged bush from some 6061 aluminium.
This bush has an approx .025mm (.001") interference fit with the ID of the gauge, a Flange Width of approx 6mm and a depth equal to the length of the original plastic spacer supplied with the gauge.
With the supplied lens removed, I carefully pushed the bush into the gauge, being carefull not to rotate the dial so as not to loose registration.
The gauge was then fitted through the hole in the instrument cluster and the modified gauge nut installed, not too tight, to hold the gauge in position.
The Bezel thread and the flange on the new bush support the gauge on the instrument cluster base.
The flange thickness was only 1.5mm (.060"). The instrument cover will then screw down as normal.

I've seen the standard of workmanship of Gavin's gadgetry and wouldn't waste my time trying to come up with a fix myself, this is his thing.

Noel