I have officially completed 3 P7 led mods on my Mags. One thing I discovered was how tricky it can be working with such small wires and components. The first mod I put the adhesive on to thick and the led turned the "angry blue" in a couple minutes so I had to pry the led off the heatsink and scrape off the adhesive and reattach it to the heatsink with a very thin layer and this eliminated my blue led. Are there any tips you might be willing to share regarding attaching, positioning, and soldering the P7 that would help me and other newbs in the future. When mounting the P7 where do you like the to put the led terminal wings relative to the holes for the wires? What size wire? Do you clip one of the terminal wings off or shorten them at all? How do you apply the adhesive without it squeezing out from between the heatsink and P7? Any other things I may need to know?
P7 mounting and soldering tips
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Al Combs
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I bought my P7 a year ago. The LITEMania heatsink I bought had the 8mm depression to center the LED machined a little too small. The result was the LED was centered, but not touching the heatsink in the center. I've never heard anyone else mention this problem. So either I got a fluke of early production, or people just glue it on without noticing the potential problem this might cause. I didn't want to touch the heatsink and ruin the insulation advantage of the anodizing. I took an X-Acto knife and scraped the edge of the LED's central slug from the side until it fit. I didn't realize it's plated copper until I removed the edge.
As far as the position of the leads, looking down at the heatsink I put the left edge of one lead even with the right edge of the hole. The second lead is to the right of the first. That way with a simple right angle bend in the wire, I can attach it to both leads. Is it really necessary to use both? No but then why not. Instead of one leg carrying 2.8 amps, you've got 2 carrying 1.4 amps each. I used 20 gauge solid copper wire. The 20 gauge Teflon would have been better. But it's what I had available at the time. Actually 24 gauge wire can carry 3.5 amps. So 20 gauge is just comfortable overkill.
I used a glob of Arctic Silver epoxy about the size of a grain of rice. I took a little bit of that an smeared it with the applicator on the back of the LED. The rest I left on in the center of the heatsink to push to the side. I figured less chance of air bubbles that way. I could see it gush out to the small gap between the plastic case and the heatsink. But it didn't come to the edge of the plastic. There was nothing to clean up. I didn't plan it that way, that's just how it came out. Like MacGyver used to say, "Better lucky than good." Speaking of cleaning up, don't forget to clean both the heatsink and the back of the LED with alcohol on a Q-Tip. Epoxy doesn't stick very well with even a trace of grease. Arctic Silver has mild capacitive properties so you couldn't pot a circuit board with it. I had both available and Arctic Silver epoxy is more thermally conductive than Arctic Alumina. It should be OK for LED mounting. I'm not sure what happens if you use so much of it the glue touches both leads of the LED. But I didn't have that problem.
I cut the lugs off the LED to within about 1mm of the plastic. Since I was using solid copper wire, I removed the insulation. With the LED epoxied onto the heatsink, I used a toothpick jammed in the hole to hold the wire in place while I soldered it to the LED lugs. I put the insulation back on from the rear afterwards. Since it was plastic and not Teflon, I didn't want it to get all melted. The wire was flush up against the LED. That way I only had to cut the cam tube off the back of my stock MagD reflector and didn't need to enlarge the hole.
If I was doing it now I'd use the 20 gauge silver coated stranded Teflon wire. By cutting the LED lugs half way down the vertical drop between the first and second bend in the lug, a screwdriver could be used to bend the tip of the lug around the wire. That way there's nothing to hold while soldering. And still plenty of room to fit inside the reflector. If you have really good flush cutters, you could make the cut after bending it around the wire. That might be easier than figuring the length beforehand.
Hope someone finds any of this useful.:wave:
As far as the position of the leads, looking down at the heatsink I put the left edge of one lead even with the right edge of the hole. The second lead is to the right of the first. That way with a simple right angle bend in the wire, I can attach it to both leads. Is it really necessary to use both? No but then why not. Instead of one leg carrying 2.8 amps, you've got 2 carrying 1.4 amps each. I used 20 gauge solid copper wire. The 20 gauge Teflon would have been better. But it's what I had available at the time. Actually 24 gauge wire can carry 3.5 amps. So 20 gauge is just comfortable overkill.
I used a glob of Arctic Silver epoxy about the size of a grain of rice. I took a little bit of that an smeared it with the applicator on the back of the LED. The rest I left on in the center of the heatsink to push to the side. I figured less chance of air bubbles that way. I could see it gush out to the small gap between the plastic case and the heatsink. But it didn't come to the edge of the plastic. There was nothing to clean up. I didn't plan it that way, that's just how it came out. Like MacGyver used to say, "Better lucky than good." Speaking of cleaning up, don't forget to clean both the heatsink and the back of the LED with alcohol on a Q-Tip. Epoxy doesn't stick very well with even a trace of grease. Arctic Silver has mild capacitive properties so you couldn't pot a circuit board with it. I had both available and Arctic Silver epoxy is more thermally conductive than Arctic Alumina. It should be OK for LED mounting. I'm not sure what happens if you use so much of it the glue touches both leads of the LED. But I didn't have that problem.
I cut the lugs off the LED to within about 1mm of the plastic. Since I was using solid copper wire, I removed the insulation. With the LED epoxied onto the heatsink, I used a toothpick jammed in the hole to hold the wire in place while I soldered it to the LED lugs. I put the insulation back on from the rear afterwards. Since it was plastic and not Teflon, I didn't want it to get all melted. The wire was flush up against the LED. That way I only had to cut the cam tube off the back of my stock MagD reflector and didn't need to enlarge the hole.
If I was doing it now I'd use the 20 gauge silver coated stranded Teflon wire. By cutting the LED lugs half way down the vertical drop between the first and second bend in the lug, a screwdriver could be used to bend the tip of the lug around the wire. That way there's nothing to hold while soldering. And still plenty of room to fit inside the reflector. If you have really good flush cutters, you could make the cut after bending it around the wire. That might be easier than figuring the length beforehand.
Hope someone finds any of this useful.:wave:
supasizefries
Enlightened
I've only built one P7 Mag so far but I will tell you my experiences with it. I'm not saying my build is the end all be all, but it has worked for me quite well. I don't know what epoxy you used, but it sounds like it didn't conduct heat so well. After reading numerous threads here, I decided to use AA epoxy. I used a VERY small amount, like a drop which I put on the back of the emitter. The AA comes in 2 parts which have to be mixed. I mixed both parts together and took a drop's worth with a little plastic paddle that was included when I bought the stuff. It spread out just enough to cover the metal slug on the back. No spill out the sides at all. I clipped the wings off the emitter and lined them up straight above the holes in the heatsink. I used 24 AWG teflon wire bought from someone here on the forums. Hope this helps.
Justin Case
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Regarding thermal path for the P7:
You could use Arctic Alumina (or Arctic Silver) thermal compound under the slug. Since it's not an epoxy, you have infinite time to get the layer thickness right. Plus, thermal compound has better thermal conductivity than thermal epoxy. Then use some AA epoxy or even regular epoxy around the P7's case to secure the LED to the heat sink.
Hookup wires:
For drivers, I've used only the 14mm drivers from The Shoppe (e.g., SOB and BadBoy Nexgen). That pretty much requires me to use 24 gauge wire max. For direct drive, I've used 22 gauge. All wire is stranded and Teflon-jacketed. I keep the wire lengths as short as reasonably possible. Longest run is probably about 3" (switch to driver). From the driver to the LED, the wires are probably about 1" long.
The LED leads:
I trim them to leave only the small horizontal part remaining. I want to make sure that they don't extend too far out and come anywhere near the edge of the reflector opening. I position the leads slightly to the sides of the holes in the heat sink.
For soldering:
I run the wires from the driver (or switch, for direct drive) straight up the holes in the heat sink. I trim the length of the wires so that they are flush with the top of the P7's black case. I strip just a little piece of Teflon insulation to expose the conductor. I pre-tin both the wires and the LED leads. Then I solder the wires on the sides of the P7's leads. I don't put any sort of 90 degree bend to lay the wire on top of the leads. It is very easy to get a good solder joint and it is also very easy to push the wire absolutely flush against the LED's case to provide the maximum clearance from the reflector opening.
You could use Arctic Alumina (or Arctic Silver) thermal compound under the slug. Since it's not an epoxy, you have infinite time to get the layer thickness right. Plus, thermal compound has better thermal conductivity than thermal epoxy. Then use some AA epoxy or even regular epoxy around the P7's case to secure the LED to the heat sink.
Hookup wires:
For drivers, I've used only the 14mm drivers from The Shoppe (e.g., SOB and BadBoy Nexgen). That pretty much requires me to use 24 gauge wire max. For direct drive, I've used 22 gauge. All wire is stranded and Teflon-jacketed. I keep the wire lengths as short as reasonably possible. Longest run is probably about 3" (switch to driver). From the driver to the LED, the wires are probably about 1" long.
The LED leads:
I trim them to leave only the small horizontal part remaining. I want to make sure that they don't extend too far out and come anywhere near the edge of the reflector opening. I position the leads slightly to the sides of the holes in the heat sink.
For soldering:
I run the wires from the driver (or switch, for direct drive) straight up the holes in the heat sink. I trim the length of the wires so that they are flush with the top of the P7's black case. I strip just a little piece of Teflon insulation to expose the conductor. I pre-tin both the wires and the LED leads. Then I solder the wires on the sides of the P7's leads. I don't put any sort of 90 degree bend to lay the wire on top of the leads. It is very easy to get a good solder joint and it is also very easy to push the wire absolutely flush against the LED's case to provide the maximum clearance from the reflector opening.
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Wow thanks for all the great replies. I used AA epoxy. I found that you need to keep the led leads soldered as close as possible to leave room for the reflector. Also when using a stock Mag smooth reflector, that the centering of the led, the size of the soldering and the excess AA that came out from the led all had an impact on the quality of the beam and artifacts. Also that a MOP reflector smoothed out the beam and hotspot and gave more flood but I lost alot of throw.
Justin Case
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IMO, a Seoul P4 works much better than a P7 with the stock Mag reflector.
When focused to a tight beam, the P4 has an excellent beam pattern with a nice spill and a very bright hot spot. The pattern is almost defect free (just a moderately bright, thin ring in the spill beam).
I get 19,000 lux at 1 meter for the P4 using the smooth Mag reflector.
In contrast, the P7 beam is not as tightly focused so the hot spot is not as bright unless you really push the P7 to the max (i.e., 2.8A drive current). The hot spot also has various defects in it, although against real world backgrounds, it's probably not noticeable. The spill is brighter since the P7 puts out more total lumens.
Definitely, an OP reflector like the KD smooths out the beam very nicely, but as was said above, you lose a lot of throw.
Also, a non-"C" serial numbered CMag can be mod'ed fairly easily. By wrapping layers of aluminum foil around a 4sevens heat sink, you can fill in the ~1mm gap between the heat sink and the Mag tube. Now, I've done this only for a cool-running configuration (P7 driven at 250mA per core), so I can't say how well this would work for a full-powered P7 mod driven at 700mA per core.
A non-"D" serial numbered DMag can't be mod'edeasily, at least with a 4sevens heat sink. The sink diameter is smaller than the ID of the DMag tube.
When focused to a tight beam, the P4 has an excellent beam pattern with a nice spill and a very bright hot spot. The pattern is almost defect free (just a moderately bright, thin ring in the spill beam).
I get 19,000 lux at 1 meter for the P4 using the smooth Mag reflector.
In contrast, the P7 beam is not as tightly focused so the hot spot is not as bright unless you really push the P7 to the max (i.e., 2.8A drive current). The hot spot also has various defects in it, although against real world backgrounds, it's probably not noticeable. The spill is brighter since the P7 puts out more total lumens.
Definitely, an OP reflector like the KD smooths out the beam very nicely, but as was said above, you lose a lot of throw.
Also, a non-"C" serial numbered CMag can be mod'ed fairly easily. By wrapping layers of aluminum foil around a 4sevens heat sink, you can fill in the ~1mm gap between the heat sink and the Mag tube. Now, I've done this only for a cool-running configuration (P7 driven at 250mA per core), so I can't say how well this would work for a full-powered P7 mod driven at 700mA per core.
A non-"D" serial numbered DMag can't be mod'edeasily, at least with a 4sevens heat sink. The sink diameter is smaller than the ID of the DMag tube.
I am a newbie to flashlight mods but I just finished my P7 yesterday. Here's what I learned:
1. I used the DHS heatsink which made centering easy. Use very little Alumina epoxy because it will come out. I read that the bottom of the P7 is concave and you should sand it down. I didn't know this so I didn't.
2. You may have to sand the DHS heatsink to get it to fit inside the D body. I later found out it would have been better to sandt he body since HAIII is not easy to sand. Oh well, worked for me. Very tight fit though and I have to rotate it to just the right spot. Obviously I didn't sand evenly. Good thermal contact though.
3. Put thermal compound between the HS and the flashlight body.
4. I had flickering issues which I think had to do with bad thermal management. When everything settled and the HS was inside the body and the compound heated up, it stopped flickering. Weird.
5. TIP: Do not solder the board to the switch OUTSIDE the body. I didn't know this until it was too late. The switch can only go in from the battery end. Lame.
6. Cut the legs really short and be smart about how you attach the wires.
7. Speaking of wires, thicker gauge is not always better. I went from 20 gauge to 24 gauge. Thinner wire means less sticking out and possibly shorting on the reflector.
8. Despite this, I had shorting problems but enough tightening and loosening resulted in the reflector "molding" the leads and wires so no more problem. I need to fix some soldering when I get home since one of the wires got frayed.
9. Holding a wire to the positve and negative points in the switch while it's in the body and trying to stick a soldering iron down the hole and attaching the two is very very difficult.
The end! That's what I learned. Hope this helps.
1. I used the DHS heatsink which made centering easy. Use very little Alumina epoxy because it will come out. I read that the bottom of the P7 is concave and you should sand it down. I didn't know this so I didn't.
2. You may have to sand the DHS heatsink to get it to fit inside the D body. I later found out it would have been better to sandt he body since HAIII is not easy to sand. Oh well, worked for me. Very tight fit though and I have to rotate it to just the right spot. Obviously I didn't sand evenly. Good thermal contact though.
3. Put thermal compound between the HS and the flashlight body.
4. I had flickering issues which I think had to do with bad thermal management. When everything settled and the HS was inside the body and the compound heated up, it stopped flickering. Weird.
5. TIP: Do not solder the board to the switch OUTSIDE the body. I didn't know this until it was too late. The switch can only go in from the battery end. Lame.
6. Cut the legs really short and be smart about how you attach the wires.
7. Speaking of wires, thicker gauge is not always better. I went from 20 gauge to 24 gauge. Thinner wire means less sticking out and possibly shorting on the reflector.
8. Despite this, I had shorting problems but enough tightening and loosening resulted in the reflector "molding" the leads and wires so no more problem. I need to fix some soldering when I get home since one of the wires got frayed.
9. Holding a wire to the positve and negative points in the switch while it's in the body and trying to stick a soldering iron down the hole and attaching the two is very very difficult.
The end! That's what I learned. Hope this helps.
Justin Case
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Re: #5 and #9, hard wire your switch with a wire soldered to the switch + and a wire soldered to the switch -. It is easiest to do this soldering if you remove the switch from the Mag body first. It also may not be necessary to cut off the plastic switch tower. It depends on the heat sink and the size of the driver board (if any). If you have the new Mag switch design that has the blue switch core that you can push out of the switch body, then there is no need to have to do any soldering down the narrow switch tower opening. If you have the older switch design that uses the brownish plastic tower, you can either cut off the tower, or disassemble the switch and remove the tower intact (saving it if you ever want to revert back to the stock configuration).
Re: #7, If your soldering is tidy and you use good techniques for getting the wires soldered in-close to the P7, you can definitely use 22 gauge wire and maintain comfortable clearance away from the reflector. I've not used anything thicker, so I won't make any further claims. I agree, however, that 24 gauge makes achieving the desired clearance even easier. Plus, 24 gauge is more supple than 22 gauge. For the short wire lengths, there is probably little practical reason to require wire thicker than 24 gauge.
Pre-tinning everything that needs to be soldered really helps. I also use IPA to clean all surfaces (including the P7 slug) that will be thermal epoxied or covered in thermal compound.
A lintless eyeglass cloth and IPA are very effective in cleaning the P7's gummy dome, which collects debris very quickly.
CPF member Yellow is a big proponent of using thermal compound, not thermal epoxy, underneath LED slugs. Then you use epoxy to secure the circumference of the LED. If your application can accommodate this method, I think it is the correct way to go in terms of thermal management. P7 Mag mods can definitely use this method. Just look at the various images on CPF of folks using GITD powder mixed with epoxy and putting glow rings around the LEDs in their Mag mods. For other applications, however, I might prefer the added security of epoxy under the LED as well as around the LED.
4sevens CMag heat sinks for the SSC P4 can be easily modified for P7 usage. Just carefully grind off the centering ridge. You will still have a raised platform and an exposed, bare metal ring to help you center the P7.
Re: #7, If your soldering is tidy and you use good techniques for getting the wires soldered in-close to the P7, you can definitely use 22 gauge wire and maintain comfortable clearance away from the reflector. I've not used anything thicker, so I won't make any further claims. I agree, however, that 24 gauge makes achieving the desired clearance even easier. Plus, 24 gauge is more supple than 22 gauge. For the short wire lengths, there is probably little practical reason to require wire thicker than 24 gauge.
Pre-tinning everything that needs to be soldered really helps. I also use IPA to clean all surfaces (including the P7 slug) that will be thermal epoxied or covered in thermal compound.
A lintless eyeglass cloth and IPA are very effective in cleaning the P7's gummy dome, which collects debris very quickly.
CPF member Yellow is a big proponent of using thermal compound, not thermal epoxy, underneath LED slugs. Then you use epoxy to secure the circumference of the LED. If your application can accommodate this method, I think it is the correct way to go in terms of thermal management. P7 Mag mods can definitely use this method. Just look at the various images on CPF of folks using GITD powder mixed with epoxy and putting glow rings around the LEDs in their Mag mods. For other applications, however, I might prefer the added security of epoxy under the LED as well as around the LED.
4sevens CMag heat sinks for the SSC P4 can be easily modified for P7 usage. Just carefully grind off the centering ridge. You will still have a raised platform and an exposed, bare metal ring to help you center the P7.
Justin Case
The issue re: switch is that two of three wires from the DW Buck Driver need to go to it. The wire is only so long. I tried wiring the driver to the switch outside of the body. Then when it came time to put it back, I put the contraption driver first and it wouldn't fit through the lockring. So I had to take everything apart.
#7 - You're right. I am sure if I was a better solderer or engineer I could figure out something better which would allow me to use thicker wires.
The issue re: switch is that two of three wires from the DW Buck Driver need to go to it. The wire is only so long. I tried wiring the driver to the switch outside of the body. Then when it came time to put it back, I put the contraption driver first and it wouldn't fit through the lockring. So I had to take everything apart.
#7 - You're right. I am sure if I was a better solderer or engineer I could figure out something better which would allow me to use thicker wires.
supasizefries
Enlightened
I did the same thing on my recent tri-P7 build with DW's kit. I just removed the lock ring, stuck everything in through the top and repositioned the lock ring. The set screw in the switch does a great job holding the whole assembly in place. I had to remove the lock ring in my 623 because the high temp socket didn't fit with it on. The switch is only held in place with the set screw and I have yet to have any problems.
Justin Case
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Lock ring? You mean the ring that screws into the Mag body near the top of the tube? Isn't that for non-"C" and non-"D" serial numbered Mags? My memory is hazy, but don't the new version Mags use a little ridge inside the Mag body near the top of the tube to position the switch, which thus has to be inserted from the tail end?
How well does the der Wichtel Tri-P7 heat sink fit the larger diameter non-"D" serial numbered Mag tubes?
How well does the der Wichtel Tri-P7 heat sink fit the larger diameter non-"D" serial numbered Mag tubes?
supasizefries
Enlightened
The Mag that I used was a 4D silver body purchased from Walmart last week. I'm pretty sure it's a D serialized light. That little ridge you refer to actually is a removable ring. You can get in their with a flathead screwdriver and coax it out.
DW mentioned in his tri-p7 thread that the sink should fit into the battery tube no problem (at least the black colored mag bodies). He said that any other colors Mag might have problems, which is the case with mine. Refer to his thread (post 54, 55, 56) about his discussion. I might have to bore mine out a bit to get the bottom of the sink to fit in the tube.
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Al Combs
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The NetKidz thread on the $8 AMC7135 P7 driver shows a picture of a Deans Ultra he had available to make his P7 removable. W. S. Deans says the Deans Ultra is the equivalent of 12 gauge wire. The Deans Micro is a better bet for a P7 hookup. A Google for Deans Micro will bring up a ton of RC car sites you can buy one from.
I've seen some of the Hotwire guys say they remove the clip from the front of the MagLite so only the set screw is holding the batteries at bay. That's another possibility that costs nothing. If you drop it without the clip in place, it will probably destroy the switch.
I've seen some of the Hotwire guys say they remove the clip from the front of the MagLite so only the set screw is holding the batteries at bay. That's another possibility that costs nothing. If you drop it without the clip in place, it will probably destroy the switch.
I've thought about the Deans Micro too except anytime you buy a $2 item, the shipping is like $5. What a rip. I wish I had a hobby store near here so I could just pick some up.
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supasizefries
Enlightened
The ring is essentially "C" shaped and is held in place with tension. It sits snugly in a shallow groove inside the tube. All you have to do is get a flat head screwdriver and use it as a lever on the lip (where the gap in the ring is) of the ring and kinda twist it so you can unseat the ring from the groove. From there you can just continue unseating the ring and just pop it out.
