LED Light


#1

I’m a CNC Programmer/Manufacturing Engineer. At work there’s not much light in the machines and everyone complains about it, so I made this light. 2000 lumens, you see spots if you look directly at it. I put a magnet in it so it will stick to the machines. Works great. Took 16 hours to print and almost used the entire z axis of my Form 2.




#2

Very nice work Gerald!!! What is the cost for all the supplies to make the light (not including printing)?

Chris


#3

You going to add a lens to diffuse the light so there are no hot spots? Like a bike reflector panel?


#4

Since I just made the one I didn’t get any deals on materials. LEDs are $18/ft used 2ft
Wall adapter $15
Safety glass $50
8 m4 screws and nuts $5
Magnet $30

I’m making 10 smaller ones since the guys at work want to buy them. They will be about 1/3 the size, because the first one was overkill. Much cheaper too.


#5

I wasn’t thinking about it. Ordinarily it’s in a position where I’m not looking at it directly. That is a good idea though. Not sure where I would get a diffuser. I switched from glass to polycarbonate, which I can get locally at a plastic shop. I think all they have is clear or colored stuff. I think I’ll ask them if they can get something that would work as a diffuser.


#6

Maybe the replacement sheets they use for fluorescent lighting? Just cut off a piece.


#7

I want it to be strong in case it gets dropped on something in the machine which is very easy to do. The cutting fluid is very slippery. Maybe a frosted polycarbonate.


#8

Found these at Mcmaster carr but maybe they can send you a small piece.


#9

Frosted PC or PMMA is pretty common where I live, you should be able to find some too. Expect at least 40% of loss in the light output though…


#10

40% loss! That sounds like too much. I wonder if they make different levels of frost so there isn’t as much light lost.


#11

For real diffusing plates, that’s what you should expect. Plates that are only frosted on one side or the other will get you “better” light throughput but will no really diffuse the light, it will still be quite specular.

The only way to diffuse with better efficiency is to get a more expensive, less widely available, very thin diffusing sheet but those are not to be found everywhere, and you’d still have to expect 20 to 30% loss.


#12

McMaster-Carr is my favorite place to buy stuff.


#13

I bought a scrap of the diffuser plastic and I notice it’s not as effective the closer it gets to the light source.

I’m not sure if light loss is the best way to describe the change in light patterns a caused by a diffuser; but more of a scattering that makes it look less bright.

Besides controlling hot spots, a diffuser also works to control harsh shadows, which is what I’m after.


#14

What if the back was frosted? Try a piece and sand it?


#15

Sanding one side may work.


#16

Well if your measure LUX or Lumens output there is a loww of output. Now of course if what you are after is elimitating specular light the the output loww is acceptable but it is loss nonetheless. If you could convert the light with 100% effectiveness you could use a much less powerful light source, consume less electricity, produce less heat.

As for sanding one side this is akin to a “frosted” acrylic plate, it will kinda diffuse the light but it’ll not be a propper diffuser. Might work jsut as well though, depending on the application. I’d try to put the sanded face on the oposite side of the light soucre, I suspect having the polished side “in” and the frosted site “out” will yield btter efficency.


#17

Unfortunately I don’t have a light meter to measure the difference between diffused and non diffused light output.

I’ve tried sanding one side and both sides of the acrylic with minimal success. I’ve put the single sanded side on both sides of the light source and didn’t notice a significant difference. I also tried the same techniques with the dimpled acrylic sheet meant for the purpose with minimal success.

In my office; I have two circuit track lighting, with circuit one using eight lights pointed at the ceiling for soft diffused daylight color temperature light. The other circuit has eight lights daylight color temperature task lights.

As I mentioned in my original reply; I just want to cut down on the harshness of the shadows.


#18

Is it not more easy and faster to make these parts with your milling machine? It looks simple to make it with the CNC machine…


#19

Probably would be faster. I don’t have a CNC milling machine at home though.


#20

Does the LED light effect the resin in any way? LEDs emit a tiny tiny tiny amount of UV. I can tune the LED to a specific KELVIN and Nm to shed some light on the build and stay away from curing the resin. Any body know the Nm or Kevin that would be best ?