Thought it may be useful to anyone who wants to upgrade theirs to 70.2
I wish I had taken more pictures
Bezel, glass and reflector removed, it is glued, but after being run on turbo a few times weakens it. Soldering quality not the worst but not the best.
Desoldered and MCPCB removed, lots of thermal interface paste! There is a brass insert/plug which I believe is attached to the primary heatsink that the fan surrounds.
Emitters desoldered, I found the best way was to use the back of a cast iron pan on the gas hob, as trying to maintain temp on a large MCPCB using hot air was challenging.
Not impressed with the poor adhesion, probably a contributing factor in the high failure rate of the DX80, in my opinion they have used a solder with a low flux content to avoid having to manually clean the board.
While the board was hot, i took the chance to clean off the old solder (I wish I had got a pic but the contact between the thermal pad and board was not great)
The resistors are just 0 ohm bridges for 12V Cree configuration. I am not sure why they didn’t just increase the heatpad like this
New emitters flowed on using good old 63/37 leaded solder, bit of a mess with the flux… Top tip, clean it off while its cooling with an artists brush and 99% IPA
Tested each one, to my surprise they all worked first time.
Board cleaned, PCB varnish applied to resistors, ready for reinstall.
Reinstalled with MX4 and resoldered