Aluminum oxide, either by virtue of anodizing where an even and hard film is induced by high current or from sitting exposed to air, is non electrically conductive. The McClickie pak requires electricity to enter into the pak where the ground ring of the Clickie switch is in contact with it and electricity will typically leave the pak at the front face on the lip of the pak. At these two areas, you want good low resistance and that means no oxidation and certainly no anodize. The aluminum McClickie paks I had made that were part of the Aleph Mule McClickie hosts were plated with nickel because nickel is a good and reasonably durable film which is electrically conductive. Titanium which oxidizes to some extent almost immediately when in the presence of oxygen is also electrically conductive.
A hard anodized McClickie pak would need to be raw Al or plated with something other than anodize at the electrical passage points. This would add to the cost of the parts and then what are they to be matched up with? Existing hard anodized heads from SF and others? Ha! Until I am blue in the face I will maintain that hard anodize is first and foremost a structural and durable film added to protect the raw Al substrate. It is not a cosmetic coating and yet a strong and verbal group on CPF insist otherwise. So be it!
I have some unwritten guidelines and priorities in what ever I am working on or bringing to CPF and in the case of hard anodize, I want the complete part hard anodized as I feel this allows for maximum protection of the part. The heads and sleeves of the Al PD sets were all anodized with no masking or breaking of the anodize film required. It also took me a few years to work through the first set of those parts which I had machined. Things were much slower back then with some improvements in the Luxeon LED's but that was about it in terms of technology change.
Any run in aluminum has to be in relative large numbers for me and this represents significant labor and assembly time. I have more than enough on my plate with the titanium which I prefer in terms of longevity and durability. As a niche, even the titanium is now being visited by many and I have to tread carefully!! :thinking:
Yes, I skipped the question initially. Although I think hard anodize is a good and viable film for aluminum and I think aluminum is a good material for flashlights, if I can avoid building in the material and using anodize I will and gladly so. I am not sure I could even be civil to someone complaining about a cosmetic aspect of anodize to me and it is best I avoid any chance of this happening! My priorities are low to no maintenance both in the lights I build and cosmetic considerations for certain.
Some focus on the light itself and how it looks and feels. Some focus on the beam that comes from the light. My focus is on what the beam itself can and will do and with hopes that that beam will be there and available regardless of the time in service and environment the light is used in.
If a new and improved E-series head comes out 10 years from now, it is my hope and expectation that one of these Ti McClickie paks would be there and ready and able to serve as host to such a head. Scratches and dings and battle scars have nothing to do with its ability to "serve".