I was curious about the highest quality manufacturers in China.
I don't believe you understand how manufacturing is done in China :nana:
Say that my company, Brand X Lights, wants to have components built in China. I don't build a factory, buy machinery, hire workers, etc. - instead, my company finds a broker like Phase II or Gateway to China who looks at available facilities & matches buyer & seller. Fenix operates the same way - there is no "Fenix Factory" in China, they contract with any shop that can make the parts for the price ... there are (best I can tell)
no manufacturers (per se) in China, but there are lots of shops that will manufacture to your spec. That can cause problems down the road, as Shop #1 (used in 2009) and Shop #2 (used in 2010 because they are cheaper) use different calibration standards ... so there may be no parts interchangeability between lights made last year & lights made today.
If you want or need "highest quality", use only an ISO certified shop. At least they have a written standard with which they must comply or they stand to lose the ISO cert. When your parts arrive here, set up a decent QC lab &
inspect 100% of the parts. Then you retain some control over what is being sold.
For a QC lab, nothing fancy is needed, just build a temp controlled clean room with HEPA filtration (as you aren't building knee replacements or other medical/aerospace parts). I've priced out site built clean rooms & they are not expensive, around $5k to $10k for a smallish room (about 200 square feet). More info here:
http://www.coastwidelabs.com/Technical Articles/Cleaning the Cleanroom.htm Once the clean room is built, you'll need standard inspection tooling like an optical comparator, height gage, gage block set, surface plate, micrometers & calipers, etc. And then you'll need to hire an experienced QC inspector.
Paxton Products just brought out a HEPA filtered blower used for pressurizing clean rooms. They say it's suitable for use in a Class 10,000 clean room:
http://paxtonpureair.com/
Unless you plan to inspect 100% of the parts, you'll have no idea how close they are to print dimensions. And just because the parts start off in compliance, that can change overnight. Constant inspection is the key to selling something made by someone else. Especially when you have almost zero control over the process.