I just got done modifying my Apex, and thought I would share how I did it.
Princeton-Tech Apex, Spotlight LED Modification
Stock Apex
This is the technical paper that describes how to modify a Princeton-Tech Apex Headlamp by replacing the stock Luxeon LED emitter (60 lumen rating), with a Seoul P4 LED emitter (130 lumen rating). The estimated cost to upgrade the Apex is $20.00. The estimated time to make the modification is 20 - 30 minutes.
Required Parts:
· (1) Princeton-Tech Apex: $55.00 (Ebay, New Condition)
· (1) LED Emitter:
o SSC P4 Emitter, USWOH (pure white color): $10.00
o SSC P4 Emitter, USVOH (warmer sunlight color): $10.00
· (1) 20mm Reflector:
o Khatod Smooth Reflector for the Seoul P4, 20mm: $4.00
o Khatod Stippled Reflector for the Seoul P4, 20mm: $4.00
o A stippled reflector will provide a more diffused light (less lighting artifacts than a smooth/shiny reflector, but you'll lose a few lumens in light output)
o You might consider buying (2) reflectors in case you screw up the first one during its modification (see Step 5 below). You'll need to reduce its length by sanding down one end.
· (1) Arctic Silver 5 High-Density Thermal Compound, 3.5 Gram Tube Price: $7.90
Required Tools & Supplies
· Medium Grit Sandpaper (or Sanding Block)
· Dremmel with a small, skinny grinding bit
· Soldering Gun
· Solder
· Small Phillips Screwdriver
· Needle Nose Pliers
· Q-Tips
· And Patience (don't get into a hurry)
Parts Supplier:
· The LED Emitter, 20mm Reflector, and the Thermal Compound can be purchase from Fred Pilon at PhotonFanatic. You can contact him by email to set-up your order.
o There is a $20.00 minimum order
o They accept cash payments to their Paypal
(account: [email protected])
o Supplier sales thread on CPF: PhotonFanatic,
Email: [email protected]
Before You Begin (Comments):
· You may want to use a bench vice to hold the Apex head unit in place, while you work on it. If so, you may want to place a piece of material between the head unit and the bench vice metal parts to protect the head unit from damage. Be careful not to tighten the bench vice too tight (may damage head unit). Note: A bench vice is not required. I did my Apex mod on the basement floor.
· Make sure you have all of your "required parts" and "required tools & supplies" prepared before you begin the modification.
· The stock clear optic and its holder will work, but the Khatod reflector is designed to work with the new P4 Emitter (better beam focus, fewer light artifacts). Whether you stay with the stock optic and holder is a personal preference/choice.
· When installing the new emitter, be very careful to not damage the gummy dome lens while trying to press the emitter into place. It can be easily damaged!
· You'll need to slightly modify the new reflector by sanding down an end to get it to fit (it's a little long – see Step 5 below).
· Make sure there are no batteries installed in the Apex when you begin the modification
· Read each Step carefully, before you take action.
· Note: The stock clear optic will not fit into the new 20mm reflector
Apex Modification:
Step 1: Open Case
· Disconnect the elastic headband strapping for the Apex Head Unit (removes an interference issue while you work on the light. Makes it easier to work on the head unit)
· Using a small Phillips screwdriver, unscrew the (1) screw which holds on the backplate
· Using a small Phillips screwdriver, unscrew the (3) screws that hold together the head unit
· Open up the head unit
------------> --------------------> ------------------>
Step 2: Remove the stock Luxeon LED Emitter
· Remove the clear optic and its holder (they simply pull out)
· The Luxeon LED is not glued or attached to the plastic housing in any special way. The LED is held into position by a clearance fit in its plastic housing, and by the pressure of the clear optic. To remove the LED, gently pull on the red and black wires in an alternating fashion, and wiggle the LED out of its plastic housing. It should pop-out somewhat easily.
· Desolder the Luxeon Led from the wires and remove it
--------------> ------------------> ------------------>
Step 3: Grind off the "old" Reflector Guide Nubs on the Plastic Housing
· Only do this step if you are going to use the Khatod Reflector, else go to Step 4
· Using a dremmel and the narrow grinding bit, grind off (smooth) the two small plastic alignment nubs. These are the little nubs at 3 and 9o'clock in the plastic housing around the emitter, which fit into the holes of the clear optic holder. The nubs will interfere with the seating of the new reflector.
· After you grind them off, there may be some small plastic debris bits on the heatsink. You can use a Q-Tip to remove them.
Step 4: Install new Seoul P4 LED Emitter
· Bend the ( + and - ) tabs of new SSC P4 emitter "up". You don't want them to touch the metal heatsink
· Solder the wires to the P4 tabs. Make sure the polarity is correct (black wire goes to side with the notch or cathode mark). Take your time!
· Test the Emitter:
o Install the AA Batteries
o Quickly test the new Emitter to ensure you have it wired correctly
o Remove the Batteries
· Using a Q-Tip, wipe off the "old" thermal paste from the heatsink surface.
· Add a light, even layer of "new" thermal paste to the bottom of the new emitter.
· Install the new emitter into the plastic housing. Remember to take your time and be patient. Don't press on the gummy dome on the new LED!
· Note: the new emitter is held in place by the thermal paste, the clearance fit in the plastic "housing" that surrounds the emitter, and the pressure from the new reflector.
Step 5: Install the new Reflector:
· If you are using the stock clear optic and holder, you can re-install them without making any changes. Go on to Step 6.
· If you are going to use the new 20mm Khatod Reflector, then:
o To make the new reflector fit into the Apex head unit, you'll need sand the top of the reflector (not the base) to shorten it. Below you can see I am using a sanding block (med grit) to sand material off the top of the new reflector. You can use the stock clear optic and holder to help gage the required size, and how much sanding is required. You'll only need to sand off about 0.5mm.
o I would recommend turning the reflector periodically as you are sanding to help keep it level
o I would recommend after you make a few sanding passes, you check the reflector size to help prevent sanding it down too short. You want it to be a snug fit between the plastic housing and the front lens of the head unit.
o To remove the dust from the reflector after sanding, it is suggested to swish in some dish detergent, then rinse under a strong stream of running water, shake it off well, spray some Isopropyl alcohol on it and then blow dry.
o If you purchased a 2nd reflector, you have a back-up incase you screw up the first one. Not a bad idea, since the reflectors are so inexpensive.
o Make sure the reflector seats well against the plastic housing.
Step 6: Reassemble Apex Head Unit:
· Reassemble the Apex Head Unit (Reverse of Step #1) taking care to fit the plastic backplate/heatsink cover BEFORE you install the two top screws pictured.
* You're done, and you have a Killer Light!
Modified Apex
Comparison Princeton-Tech Apex (60 lumen to 130 lumen)
60 lumen, 14 paces from wall (stock optic)
130 lumen, 14 paces from wall (new "smooth" Khatod reflector)
Princeton-Tech Apex, Spotlight LED Modification
Stock Apex
This is the technical paper that describes how to modify a Princeton-Tech Apex Headlamp by replacing the stock Luxeon LED emitter (60 lumen rating), with a Seoul P4 LED emitter (130 lumen rating). The estimated cost to upgrade the Apex is $20.00. The estimated time to make the modification is 20 - 30 minutes.
Required Parts:
· (1) Princeton-Tech Apex: $55.00 (Ebay, New Condition)
· (1) LED Emitter:
o SSC P4 Emitter, USWOH (pure white color): $10.00
o SSC P4 Emitter, USVOH (warmer sunlight color): $10.00
· (1) 20mm Reflector:
o Khatod Smooth Reflector for the Seoul P4, 20mm: $4.00
o Khatod Stippled Reflector for the Seoul P4, 20mm: $4.00
o A stippled reflector will provide a more diffused light (less lighting artifacts than a smooth/shiny reflector, but you'll lose a few lumens in light output)
o You might consider buying (2) reflectors in case you screw up the first one during its modification (see Step 5 below). You'll need to reduce its length by sanding down one end.
· (1) Arctic Silver 5 High-Density Thermal Compound, 3.5 Gram Tube Price: $7.90
Required Tools & Supplies
· Medium Grit Sandpaper (or Sanding Block)
· Dremmel with a small, skinny grinding bit
· Soldering Gun
· Solder
· Small Phillips Screwdriver
· Needle Nose Pliers
· Q-Tips
· And Patience (don't get into a hurry)
Parts Supplier:
· The LED Emitter, 20mm Reflector, and the Thermal Compound can be purchase from Fred Pilon at PhotonFanatic. You can contact him by email to set-up your order.
o There is a $20.00 minimum order
o They accept cash payments to their Paypal
(account: [email protected])
o Supplier sales thread on CPF: PhotonFanatic,
Email: [email protected]
Before You Begin (Comments):
· You may want to use a bench vice to hold the Apex head unit in place, while you work on it. If so, you may want to place a piece of material between the head unit and the bench vice metal parts to protect the head unit from damage. Be careful not to tighten the bench vice too tight (may damage head unit). Note: A bench vice is not required. I did my Apex mod on the basement floor.
· Make sure you have all of your "required parts" and "required tools & supplies" prepared before you begin the modification.
· The stock clear optic and its holder will work, but the Khatod reflector is designed to work with the new P4 Emitter (better beam focus, fewer light artifacts). Whether you stay with the stock optic and holder is a personal preference/choice.
· When installing the new emitter, be very careful to not damage the gummy dome lens while trying to press the emitter into place. It can be easily damaged!
· You'll need to slightly modify the new reflector by sanding down an end to get it to fit (it's a little long – see Step 5 below).
· Make sure there are no batteries installed in the Apex when you begin the modification
· Read each Step carefully, before you take action.
· Note: The stock clear optic will not fit into the new 20mm reflector
Apex Modification:
Step 1: Open Case
· Disconnect the elastic headband strapping for the Apex Head Unit (removes an interference issue while you work on the light. Makes it easier to work on the head unit)
· Using a small Phillips screwdriver, unscrew the (1) screw which holds on the backplate
· Using a small Phillips screwdriver, unscrew the (3) screws that hold together the head unit
· Open up the head unit
------------> --------------------> ------------------>
Step 2: Remove the stock Luxeon LED Emitter
· Remove the clear optic and its holder (they simply pull out)
· The Luxeon LED is not glued or attached to the plastic housing in any special way. The LED is held into position by a clearance fit in its plastic housing, and by the pressure of the clear optic. To remove the LED, gently pull on the red and black wires in an alternating fashion, and wiggle the LED out of its plastic housing. It should pop-out somewhat easily.
· Desolder the Luxeon Led from the wires and remove it
--------------> ------------------> ------------------>
Step 3: Grind off the "old" Reflector Guide Nubs on the Plastic Housing
· Only do this step if you are going to use the Khatod Reflector, else go to Step 4
· Using a dremmel and the narrow grinding bit, grind off (smooth) the two small plastic alignment nubs. These are the little nubs at 3 and 9o'clock in the plastic housing around the emitter, which fit into the holes of the clear optic holder. The nubs will interfere with the seating of the new reflector.
· After you grind them off, there may be some small plastic debris bits on the heatsink. You can use a Q-Tip to remove them.
Step 4: Install new Seoul P4 LED Emitter
· Bend the ( + and - ) tabs of new SSC P4 emitter "up". You don't want them to touch the metal heatsink
· Solder the wires to the P4 tabs. Make sure the polarity is correct (black wire goes to side with the notch or cathode mark). Take your time!
· Test the Emitter:
o Install the AA Batteries
o Quickly test the new Emitter to ensure you have it wired correctly
o Remove the Batteries
· Using a Q-Tip, wipe off the "old" thermal paste from the heatsink surface.
· Add a light, even layer of "new" thermal paste to the bottom of the new emitter.
· Install the new emitter into the plastic housing. Remember to take your time and be patient. Don't press on the gummy dome on the new LED!
· Note: the new emitter is held in place by the thermal paste, the clearance fit in the plastic "housing" that surrounds the emitter, and the pressure from the new reflector.
Step 5: Install the new Reflector:
· If you are using the stock clear optic and holder, you can re-install them without making any changes. Go on to Step 6.
· If you are going to use the new 20mm Khatod Reflector, then:
o To make the new reflector fit into the Apex head unit, you'll need sand the top of the reflector (not the base) to shorten it. Below you can see I am using a sanding block (med grit) to sand material off the top of the new reflector. You can use the stock clear optic and holder to help gage the required size, and how much sanding is required. You'll only need to sand off about 0.5mm.
o I would recommend turning the reflector periodically as you are sanding to help keep it level
o I would recommend after you make a few sanding passes, you check the reflector size to help prevent sanding it down too short. You want it to be a snug fit between the plastic housing and the front lens of the head unit.
o To remove the dust from the reflector after sanding, it is suggested to swish in some dish detergent, then rinse under a strong stream of running water, shake it off well, spray some Isopropyl alcohol on it and then blow dry.
o If you purchased a 2nd reflector, you have a back-up incase you screw up the first one. Not a bad idea, since the reflectors are so inexpensive.
o Make sure the reflector seats well against the plastic housing.
Step 6: Reassemble Apex Head Unit:
· Reassemble the Apex Head Unit (Reverse of Step #1) taking care to fit the plastic backplate/heatsink cover BEFORE you install the two top screws pictured.
* You're done, and you have a Killer Light!
Modified Apex
Comparison Princeton-Tech Apex (60 lumen to 130 lumen)
60 lumen, 14 paces from wall (stock optic)
130 lumen, 14 paces from wall (new "smooth" Khatod reflector)
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