converting old SW ammeters to LED volt meters

This shows one of them on reading 11.3v. I choose blue thinking might be more visible in sunlight. Choices are red, green, blue, yellow.
The old studs pop out out the old ammeter gauge and white ceramic insulators and washers and nuts get reused.
Simple using a small screwdriver bend back the metal tab on the chrome bezel moving incrementally around the circumference. It opens up without cracking.
It does not need to open fully 90 degrees to clear the brass gauge housing.
When put back together, dont crimp it back down, just hot glue all around is plenty strong to keep it together.
I resealed glass face to chrome rubber ring using small amount of permatek #2. Just to make sure glass remains watertight to the chrome bezel..

I did put some blue painters tape on the top of the soldered brass bolts for insulation, in case the LED meter hot glued to the glass comes loose. Dont want it shorting out.



led circuit hot glued onto glass, Be careful NOT to scrape the painted glass face or you will mar the black appearance.



assembled gauge hot glued together. I used my solder gun to smooth-flatten the hot glue bead after using the hot glue gun.



old gauges



And keep the drain hole pointing down.
The white plastic plug forces you to sightly twist away from pure straight down when assembling the gauge due to the height of the ceramic insulator, but the drain hole only is off about 10 degrees from straight down. PLenty enough down to still drain water if it got in there.

Here is the link to those LED volt meters.
The blue is very bright.
http://www.ebay.com/itm/29124148155...49&var=590394305409&ssPageName=STRK:MEBIDX:IT

The circuit board pops out of the black surround. There is an adjustment pot on the back, I found the gauges were reading ok.

 

I decided to redo the meters as the white unlit segments of the led are too white compared to the lit blue color of the led.
In bright sun, that made it harder to read.
So I found a translucent blue plastic lid from a food container and cut into a circle.
With a couple dabs, glued the plastic to the inside of the black paint with permatek.
Then carefully aligned the meter to the inside so it fits perfectly and the glue is mounting the meter to the metal ring instead of the glass face.

Doing this makes it easier to read in the sunlight.





And result is a beautiful looking LED gauge. My cost was $5 for both of them. The hot glue does not have to seal all the way round.
This time I staggered the glue in fifths.