Yo, answers
What machine?
We have 13 CNC machines in total, so I'm not sure what your asking?
The first 250 cases where made on the prototyping / tool room mill, but all others have since been produced using one of our high speed (20,000 rpm) production mills, designed specifically for aluminum.
The D-Tek Mark I should all have been type III, the blue units with "c-systems" are likely just type II. But since we have had mark I's in a tank for over year, and none show any corrosion (expect the bolts on one batch) , I think it's a dead issue. You should also note we moved to 6063 alloy too enhance resistance.
I believe what you guys have seen in the past, was galvanic.
later, busy busy