Soldering questions? On IC chips and Charge Ports
I can't seem to find a satisfactory reply to my questions, all the results I've seen are very ambiguous. Please help me understand if you have correct knowledge.
Recently I've been studying soldering.
I'm 20 years old and opened a phone and computer repair shop a year ago in Houston tx. Although it is doing well, I need to learn more things to make it more competitive. I know very basic things like screen repair, unlocks and imei repair, computer software/OS restores, changing ram and hard drives, Refurbishing lcds with machines, etc. however, I would like to take it a step further ( and I also just love learning anything to do with tech stuff haha) and start soldering ( as this is a universal trade also and can be used to fix electronics from aircrafts to medical supplies to casino slot machines). For now however I am finding it hard to really understand the types of flux to use.
Do I use liquid flux like Kester 751 or paste or what?
Are there different types of fluxes to use or is it all the same ( example, would you use same flux for iPhone 6 Plus touch ic as you would with a Samsung charger port repair)
What kind of flux should I use for iPhone ic chip repair and Samsung charger port repairs ( please leave a eBay link)
What type of solder should I use ( 63/37 or lead free or leaded? Is leaded even allowed in US?)
Is it possible to unlock iCloud by changing ic chips or is it to hard? (I've seen people changing memory size on iphones but can't find anything for iCloud)
Is this a good question?