My Tractor Forum banner
  • Are you passionate about Tractors? Would you like to write about topics that interest you and get paid for it? Read all about it here!
1 - 10 of 10 Posts

·
Registered
Joined
·
3,151 Posts
Discussion Starter · #1 ·
My 112 has a headlight setup that leaves something to be desired. The rubber mounts are deteriorated and stretched, and I only have one trim ring with wrinkled chrome.

Anyway, enough whining, I want to set up a bracket to support two new lamps which will mount to the existing headlight panel mounting holes, and do away with the rubber mounts. A while ago, I bought a couple 4" "trapezoid" tractor lamps which use a H3 style lamp, rather than a sealed beam. These lights can usually be found at places like Princess Auto. I got to thinking a LED conversion would help reduce the load on the small engine charging system. I've purchased some 10W warm white LEDs and drivers (AC/DC rectifier/regulator) before off ebay and used them on a few lighting projects with good results.

The disassembled replacement lamp, as well as old sealed beam, and LED components next to the H3 lamp.

The glass/reflector has the same dimensions as the sealed beam, which would allow it be used with the OE rubber mounting system.



I built a heatsink/mounting plate to sandwich the LED to the back of the reflector opening. 1.5x1.5" square of 1/8" aluminum stock. The holes will allow the LED wires to pass through, and screws will catch the rounded corners of the LED. Corresponding mounting holes were drilled in the reflector for the mounting screws. Also shown is the H3 lamp which is making an exit.



Driver leads connected to LED. Before assembly, I applied a blorp of heat sink compound to the backside of the LED for good heat transfer. I'm not sure if the heat dissipation is a necessity or not, but these units can get warm to the touch after long operation. If I was installing this via the rubber mount, I'd install the driver board(s) in a small electronic project box to protect it from the elements, and use silicone to seal around the screws/holes/gaps on the heatsink.



Powered up and compared to the old sealed beam. Sealed beam on left.

 

·
My Orange Jane Deere
Joined
·
3,356 Posts
Yes it will be nice to see just how happy you be at the end. These lights have a lot of guys always looking for better lights. :thThumbsU
 

·
Registered
Joined
·
3,151 Posts
Discussion Starter · #7 ·
Thanks for the comments guys.

7sleeper, the lens/reflector is from the new tractor lamp, which are Grote 63311-5 Trapezoid beam lamps. I simply removed the H3 lamp from the reflector and installed the LED against the back of it.

Side-by-side comparison, these LEDs are close to the light output of a 50W halogen. Unfortunately, it will be a while before the tractor is together since I just started dismantling it for it's rebuild/refurb/frankensteining.
 

·
Registered
Joined
·
543 Posts
FWIW, the Grote stuff is all very good quality. I've used some of their tractor lights in place of 4509's in my plane and they are terrific.
 

·
Registered
Joined
·
843 Posts
Thanks for the comments guys.

7sleeper, the lens/reflector is from the new tractor lamp, which are Grote 63311-5 Trapezoid beam lamps. I simply removed the H3 lamp from the reflector and installed the LED against the back of it.

Side-by-side comparison, these LEDs are close to the light output of a 50W halogen. Unfortunately, it will be a while before the tractor is together since I just started dismantling it for it's rebuild/refurb/frankensteining.
I was wondering about that, because normaly lights are designed to have their bulb in the area of mirror focus.(Not sure about my englisch here, sorry!) I believe to get a better light output the LED should be raised to the approximate height of the glowing coil of the light bulb.
I made a overly simple picture: mirror = black, light bulb = yellow, LED = red, raised LED = purple.


7
 

Attachments

·
Registered
Joined
·
3,151 Posts
Discussion Starter · #10 ·
I was wondering about that, because normaly lights are designed to have their bulb in the area of mirror focus.(Not sure about my englisch here, sorry!) I believe to get a better light output the LED should be raised to the approximate height of the glowing coil of the light bulb.
I made a overly simple picture: mirror = black, light bulb = yellow, LED = red, raised LED = purple.

7
You raise a very valid point. The light source position will affect light pattern, and of course the LED is directional, making any beam pattern nearly completely dependent on the dispersion characteristics of the fluted lens.

Some light may bounce back toward the reflector off of the lens flutes, and create a wider beam. Being as this is an off-highway application, I'm not overly concerned about optics as one would on a road vehicle.
 
1 - 10 of 10 Posts
Top