After making this light, I got contacted by somebody who asked me to make him one to use at work. His main requirement was to make it brighter. So I looked back at the compromises I made with mine, and decided to see what can I do better in this one.
So I started by buying a new host for this project at the local Lowe's:
To keep costs lower, I always try to reuse left-over stock, and I happen to have a rod of aluminum of about the right diameter:
First face off and prep for knurling:
This is the side that will hold the electronics:
Then thread the ID to match the OD on the plastic host. It was not quite 16 nor 18TPI, but I picked 18TPI, and checked often after each pass:
Not too bad:
This internal cut will be for the electrical post (details later):
HUGE chunk of Aluminum, but we are not done yet:
My customer wanted his light to be brighter than mine, so I went to XP-G's, specifically the second generation, (XP-G2), and I opted for a mix of the cool white and warm LED's, to give more output than on mine, while still preserving color rendition:
So I started work on the LED side, of course making sure the OEM plastic lens would be completely enclosed:
To hold the electrical post, I am drilling a hole in this side for a retainer screw:
Since these 18Volt packs come out at 20Volts fully charged, and since this is a PWM-dimmed, direct-drive configuration, I decided to go with 6x LED's in series:
Using my laser for positioning on the indexer:
Lots of machining:
Picking the right end-mill for the next machining operation - this will give me a little bit more throw:
Getting LED's ready for reflow soldering:
Time for the thermal epoxy:
Wire then up and test them:
You see here both the flood, and a little throw as well - this worked better than I expected:
Work on the electrical post took a long time. The idea is to "replace" the bulb, so that both the positive and negative contacts run through this post, so that the head can be interchanged without any wires/connections. This will allow this head to be used with other similarly threaded DeWalt hosts, as long as they are running from an 18Volt pack:
Drill and tap the base:
Then work on the battery side:
Then work on the Delrin piece which will hold the positive contact:
Press fit:
As designed on paper, nearly identical to the bulb it will be replacing:
Hole for the electrical positive wire:
Positive contact:
This is how it looks when inserted into the plastic host:
Then started work on the electronics. I needed a few extra boards, a few extra LED's, so I do them all at the same time since it is all surface mount components:
My Tiny85 controller boards and FET switches (for the PWM dimming) ready to go:
For the negative side of the battery, I drilled and tap a hole in the side:
Test fit of the boards. The micro controller board monitors both the battery voltage AND the temperature of the heatsink, to adjust the output automatically, and to prevent over-discharge of the pack (although one should not leave it turned on, as the pack will still have parasitic drain):
Testing phase (looks like a miniature operating room, right?):
Epoxy boards and wires in place. I am using thermal pads in each board to provide thermal path and to isolate the boards electrically (heatsink is at ground/negative potential):
More testing:
Completed module (without lens), compared to my first (prototype?) conversion:
Note the back of the controller board (white board) has all of those small holes - those are the programming pins for the Tiny85. I am in dialog with my customer via email to define his default preferences/values, as this software I wrote has 3x output levels (cycle ON-OFF-ON to cycle the levels), and also has optional memory for last level used. This makes the head re-programmable by me during this final phase of testing:
Mine/original on the left, my customer's on the right:
After all of this mambo-jumbo machining/electronics - how does it work?
(camera on manual exposure)
Old on high, then new on high:
Another set. Still a flood light, but the new one also has some throw:
From the side (note silver heatsink on right-most side of the picture):
I hope the new owner likes his new work light
So I started by buying a new host for this project at the local Lowe's:
To keep costs lower, I always try to reuse left-over stock, and I happen to have a rod of aluminum of about the right diameter:
First face off and prep for knurling:
This is the side that will hold the electronics:
Then thread the ID to match the OD on the plastic host. It was not quite 16 nor 18TPI, but I picked 18TPI, and checked often after each pass:
Not too bad:
This internal cut will be for the electrical post (details later):
HUGE chunk of Aluminum, but we are not done yet:
My customer wanted his light to be brighter than mine, so I went to XP-G's, specifically the second generation, (XP-G2), and I opted for a mix of the cool white and warm LED's, to give more output than on mine, while still preserving color rendition:
So I started work on the LED side, of course making sure the OEM plastic lens would be completely enclosed:
To hold the electrical post, I am drilling a hole in this side for a retainer screw:
Since these 18Volt packs come out at 20Volts fully charged, and since this is a PWM-dimmed, direct-drive configuration, I decided to go with 6x LED's in series:
Using my laser for positioning on the indexer:
Lots of machining:
Picking the right end-mill for the next machining operation - this will give me a little bit more throw:
Getting LED's ready for reflow soldering:
Time for the thermal epoxy:
Wire then up and test them:
You see here both the flood, and a little throw as well - this worked better than I expected:
Work on the electrical post took a long time. The idea is to "replace" the bulb, so that both the positive and negative contacts run through this post, so that the head can be interchanged without any wires/connections. This will allow this head to be used with other similarly threaded DeWalt hosts, as long as they are running from an 18Volt pack:
Drill and tap the base:
Then work on the battery side:
Then work on the Delrin piece which will hold the positive contact:
Press fit:
As designed on paper, nearly identical to the bulb it will be replacing:
Hole for the electrical positive wire:
Positive contact:
This is how it looks when inserted into the plastic host:
Then started work on the electronics. I needed a few extra boards, a few extra LED's, so I do them all at the same time since it is all surface mount components:
My Tiny85 controller boards and FET switches (for the PWM dimming) ready to go:
For the negative side of the battery, I drilled and tap a hole in the side:
Test fit of the boards. The micro controller board monitors both the battery voltage AND the temperature of the heatsink, to adjust the output automatically, and to prevent over-discharge of the pack (although one should not leave it turned on, as the pack will still have parasitic drain):
Testing phase (looks like a miniature operating room, right?):
Epoxy boards and wires in place. I am using thermal pads in each board to provide thermal path and to isolate the boards electrically (heatsink is at ground/negative potential):
More testing:
Completed module (without lens), compared to my first (prototype?) conversion:
Note the back of the controller board (white board) has all of those small holes - those are the programming pins for the Tiny85. I am in dialog with my customer via email to define his default preferences/values, as this software I wrote has 3x output levels (cycle ON-OFF-ON to cycle the levels), and also has optional memory for last level used. This makes the head re-programmable by me during this final phase of testing:
Mine/original on the left, my customer's on the right:
After all of this mambo-jumbo machining/electronics - how does it work?
(camera on manual exposure)
Old on high, then new on high:
Another set. Still a flood light, but the new one also has some throw:
From the side (note silver heatsink on right-most side of the picture):
I hope the new owner likes his new work light