D200 Reassembly thread...

[Manoet]

    This picture will prove useful as a reference later today as well as a comparison to the existing method used when the updated pic is added. Its of my original D200 thermal transfer pad layout before chrome stripping. Dunno why Devialet prefers to apply these pads by hand in "blanket" coverage wasting a L-O-T of thermal pad material, covering PCB surface that has no thermal transfer provision and thusly making areas that store but can't transfer heat efficiently. Maybe if they were paying almost $50 per sq inch for this particular thermal pad they'd be more conservative like I've chosen to be. Or better yet they'd invest a couple hundred dollars in steel rule dies that would cut their thermal pads perfectly and allow them to be affixed completely pre-spaced and aligned to cover only the areas needed or more importantly only the areas conducting heat.

Later today I'll begin laying my pads out on the PCB underside... the same way Devialet did originally but the pads transferred to the chrome side after use as chrome is smoother and more polished than the PCB and therefore easier to stick to. I shouldn't have the same problem after assembly as my soda-blasted anodized surface will be a lot less easy for the pad to adhere to and should prefer remaining on the PCB side of things.

Hard for me to gauge sq inch usage of the thermal pad material I'll use at this point but I'm guessing I'll use maybe 60-80% less thermal pad material on mine than Devialet did in this picture. Yet I will completely cover EVERY designated PCB heat-transfer point that they did with their blanket coverage but a lot less non heat-transferring circuit board! Mine will have lots of air space around and through the individual pad installation sites to enhance convection cooling. I've also decided to use a small amount of silicone spray (sprayed into a cup) then dabbed on the thermal pads via a cotton swab lightly on the exposed side of the thermal pads once secured to the PCB. This will act as a thermal interface material that prevents the pad from becoming too attached to the anodized surface and insure if I have to remove the PCB that the pads remain affixed to the PCB instead of transferring to the anodized surface as they've done on the OEM housing. This method allows for repeated PCB R&R without worrying about the pad being torn or pulled apart and damaged during removal if stuck too aggressively to 'both' surfaces.

If thing s go as planned today, tomorrow I'll move to repeating this process inside the PSU cover but there I'm going to experiment with eliminating all but the single primary thermal transfer pad. I'm betting the convection provision I've added there will more efficiently rid that covered compartment of heat than the conductive dissipation Devialet had to work with. If you want to jump ahead you can preview those pics in the PSU posts here in Tweaker's Corner.

Pic(s) of todays work when available...