Last week I modded my AceBeam K60 from the XHP70 it originally had to the XHP70.2 P2 1C I purchased from LEDDNA, it arrived well packaged in around 10 days from the date I ordered it, not bad timing at all!
I took a sample beamshot of the K60 stock LED that was a XHP70 N4 1C, probably not noticeable in the beamshot but it had a faint dark hole in the center of the beam from the separation between the dies.
The light on the left is one of my only stock lights I have a Sunwayman D40A running on turbo at approximately 950 lumens
I proceeded to open the head I had previously opened before by boiling it in a waterproof bag to loosen the thread locker AceBeam had Put in there using strap wrenches and gloves to not get burned.
Here we have the old XHP70 N4 bin 1C tint next to the new XHP70 P2 bin 1C tint that is going to be replaced with, It did not come that lubed from factory thats was why I opened it before to lube it, it makes a big difference! The ring turns smooth as butter! BTW BE CAREFUL when you open the head because there is a cavity in the selector ring with a steel ball and a spring you don't want to lose or the mode selector will not work correctly!
I proceeded to unscrew the two screws that hold the copper MPCB down and unsolder the wires then carefully pried the MPCB out of the base using needle nose pliers that I modified using a dremel for this purpose, the MPCB was a bit stubborn to get out because of the thermal grease AceBeam applied from factory, no big deal, better to have plenty than none!
Then I went ahead and cleaned all the thermal grease out of the base and MPCB to check how flat was the base... It looks nice and flat, no need to do anything to it!
Then I cleaned up the MPCB being careful not to get any thermal grease on the old XHP70 just in case I use it on another future project, after cleaning I proceded to check the underside of the MPCB to see if there was no Kapton tape like the Thrunite TN-31 had (I kid you not!) and might impede the heat transfer to the body, there was no tape to be found (Phew!) but the MPCB texture is HORRIBLE not smooth as one would expect, I really think they need to polish the MPCB the texture was so rough as a 220 to 300 grit sandpaper, Kid you not! Look at this pic!
So after I desoldered the old LED and safely stored it away, I proceeded to sand the hell out of that MPCB to get it nice and smooth to better transfer heat to the body, I used progressively finer grits until around 2000 grit and then some polish to make sure it is smooth before reflowing the new XHP70.2 LED, I think I got it right!
Almost there...
Done!
After I thoroughly cleaned the MPCB after polishing I proceeded to reflow the LED to the AceBeam copper MPCB using the electric skillet method shown in this video.
I used Mechanic Solder Paste Syringe - 63/37 - 10cc that RMM sells it works great! Just follow the instructions on the video, it was actually very easy!
Afterwards I proceeded to clean up the MPCB before inserting it back in the base. I used Arctic Silver 5 to get a good thermal path to the body of the flashlight.
When screwing down the base make sure you slowly screw one side then the other to gently apply equal pressure to the entire base and the thermal compound spreads evenly, I made sure those screws were tight, but be careful not to strip them because they are somewhat soft!
Then I soldered the 2 wires and put back the LED centering ring, relubed the selector ring and proceeded to close the head back again, making sure it makes a good seal, be careful with the tight tolerances between the reflector, the glass and the steel bezel, you may need to unscrew the steel bezel to make the light close tight!
Here is the finished mod
And an after the mod beamshot
There is no more subtle dark spot in the center of the beam and the flashlight is much brighter than stock, I would say at least 1000 lumens more but do not have testing equipment to measure, but just compare to the control flashlight SunwayMan D40A on the left!
Hope you found the mod useful!
Sincerely,
AlexGT