- Location
- Denver Adjacent
This will become an in-progress thread regarding the hurdles of swapping out the dash illumination for LEDs and changing the color.
There are a few things to consider on this swap.
1) The incandescent bulbs that are present in the factory lighting are "yellow" in terms of LED light.
2) White light is the visible combination of every color of light. Which is why it works best for illuminating a dash at night. More on this later.
3) The primary colors of white LED light are red, blue, and green. Because of this, a color tinted material will show its best color when illuminated with white light. Or! An LED of a similar color / that includes that color. Eg. Red arrows lit with red LEDs.
4) Colored LEDs ONLY emit that color. While white is still a combination of all colors, green is only green, blue is only blue, red is only red.
The end result here is that if you have a a tinted material, such as the orange speedometer needles, and you use an LED that is very far away from that color (blue) the end result will be poorly lit needles. Because the blue LED no red or yellow in it, the light will not shine through an orange material. This can be slightly overcome by sheer brightness and by the opacity of the material. The less color pigment in the material the more of the wrong color light will bleed through.
I'm not going to dive into how to take the dash apart. We're going to skip ahead to the lights.
Im using an eBay speedometer for bench testing. Because the board on the back actually stores the mileage, I'll be swapping in the board from my truck on the install. So, I rigged this.
I soldered some wires directly to the lighting circuit and hooked them to a 12v power supply.
If we look at the night illumination on a 1.5 dash, you'll notice that the stock color is white. Not yellow.
After a quick disassembly of the speedo cluster which is all snap together and not hard to figure out, you can clearly see why the dash illumination is white.
Protip: use a fork underneath the needles to GENTLY pry them straight up. (picture reference to come)
All of the "white" areas have blue tint to them. This is because of the color inconsistencies of white incandescent light. The blue tint acts on the yellow light to produce white results.
Since I'm doing a color change, that has to go. Because even if you dropped white LEDs in, guess what. The blue in the white LEDs would be enhanced by this blue coloring on the back of the gauge faces.
Enter 220 grit sandpaper.
After removing all of the blue color from the back, we now have blank slate to start from.
This works because the only part that transmits the light is the cutouts on the front. Which, so long as you're gentle with the sandpaper, will be completely unaffected.
As you can see, the true color of incandescent light.
Ewww. Gross.
I'm going to weigh some options on this. I have some green #74 LEDs already. So I'm going to bench test those, as well as some white and blue coming later this week. So I'll be able to run the gamut.
Simply popping in the green LEDs, makes a HUGE difference.
In the first picture below, I had not finished sanding the back of the gauges. You will note that the rev counter seems slight darker than the rest. The blue tint is blocking some of the green light. Because green contains both blue and yellow, the blue portion of the light is allowed through the plastic. Albeit, still with a green tone because of the overpowering color.
This picture is with the faces sanded completely. And the bezels and needles popped back on.
The needles are orange. Since orange is close to yellow, they do still illuminate slightly. Nowhere near as much as with white light. Also, note that the redline section of the rev counter is almost non visible. Red does not illuminate very well with green light. At all.
This is the extent of my testing so far. Once I receive the other LEDs, there will be more before I make up my mind about it. I will also be testing tinted films on the back of the gauge faces using white LEDs. The reason being to get the most illumination out of the needles possible while still changing to a different color for the main gauges.
There are a few things to consider on this swap.
1) The incandescent bulbs that are present in the factory lighting are "yellow" in terms of LED light.
2) White light is the visible combination of every color of light. Which is why it works best for illuminating a dash at night. More on this later.
3) The primary colors of white LED light are red, blue, and green. Because of this, a color tinted material will show its best color when illuminated with white light. Or! An LED of a similar color / that includes that color. Eg. Red arrows lit with red LEDs.
4) Colored LEDs ONLY emit that color. While white is still a combination of all colors, green is only green, blue is only blue, red is only red.
The end result here is that if you have a a tinted material, such as the orange speedometer needles, and you use an LED that is very far away from that color (blue) the end result will be poorly lit needles. Because the blue LED no red or yellow in it, the light will not shine through an orange material. This can be slightly overcome by sheer brightness and by the opacity of the material. The less color pigment in the material the more of the wrong color light will bleed through.
I'm not going to dive into how to take the dash apart. We're going to skip ahead to the lights.
Im using an eBay speedometer for bench testing. Because the board on the back actually stores the mileage, I'll be swapping in the board from my truck on the install. So, I rigged this.
I soldered some wires directly to the lighting circuit and hooked them to a 12v power supply.
If we look at the night illumination on a 1.5 dash, you'll notice that the stock color is white. Not yellow.
After a quick disassembly of the speedo cluster which is all snap together and not hard to figure out, you can clearly see why the dash illumination is white.
Protip: use a fork underneath the needles to GENTLY pry them straight up. (picture reference to come)
All of the "white" areas have blue tint to them. This is because of the color inconsistencies of white incandescent light. The blue tint acts on the yellow light to produce white results.
Since I'm doing a color change, that has to go. Because even if you dropped white LEDs in, guess what. The blue in the white LEDs would be enhanced by this blue coloring on the back of the gauge faces.
Enter 220 grit sandpaper.
After removing all of the blue color from the back, we now have blank slate to start from.
This works because the only part that transmits the light is the cutouts on the front. Which, so long as you're gentle with the sandpaper, will be completely unaffected.
As you can see, the true color of incandescent light.
Ewww. Gross.
I'm going to weigh some options on this. I have some green #74 LEDs already. So I'm going to bench test those, as well as some white and blue coming later this week. So I'll be able to run the gamut.
Simply popping in the green LEDs, makes a HUGE difference.
In the first picture below, I had not finished sanding the back of the gauges. You will note that the rev counter seems slight darker than the rest. The blue tint is blocking some of the green light. Because green contains both blue and yellow, the blue portion of the light is allowed through the plastic. Albeit, still with a green tone because of the overpowering color.
This picture is with the faces sanded completely. And the bezels and needles popped back on.
The needles are orange. Since orange is close to yellow, they do still illuminate slightly. Nowhere near as much as with white light. Also, note that the redline section of the rev counter is almost non visible. Red does not illuminate very well with green light. At all.
This is the extent of my testing so far. Once I receive the other LEDs, there will be more before I make up my mind about it. I will also be testing tinted films on the back of the gauge faces using white LEDs. The reason being to get the most illumination out of the needles possible while still changing to a different color for the main gauges.
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