field note · from the bench
What we keep in the shop, and why.
By KC Cunningham·February 14, 2026·5 min read
When you walk into the shop, the wall behind the bench is mostly drawers. Each drawer is labeled in mono with a part code. This is what's in them, and why we won't ship a repair using anything else.
OEM cells, not 'compatible'
When we replace a phone or laptop battery, we use OEM cells where they're available, and tier-A aftermarket where they aren't. We don't use the cheapest cells on AliExpress, and we don't use the unbranded cells from generic parts vendors. The reason: lithium chemistry is unforgiving. A cheap cell with a bad protection circuit is a fire hazard, and even a non-fire-hazard cheap cell typically loses 30% of its capacity inside a year.
OEM cells cost us roughly twice what the bargain cells do. We pass on enough of that cost that the customer pays for the difference, but the warranty discipline is the part that matters: when an OEM cell goes bad, we replace it under our 90-day warranty without a hassle. We can't make that promise on the bargain cells.
Spare hinges
Laptop hinges fail. They fail predictably — the plastic mounting points crack, usually around year three, and once they crack the screen wobbles or the lid won't hold a position. We keep replacement hinge kits for the most common laptops on the wall: MacBook Air 2018-onward, MacBook Pro 14 and 16 inch, ThinkPad T14 and X1, Dell XPS 13 and 15.
These aren't sexy parts. They're $40 brackets. But having them in stock means we can do a hinge replacement same-day instead of telling someone to come back next Friday. Every drawer is one less reason to make a customer wait.
Real solder paste
On the rework station, the solder paste in our syringe is from a name-brand Japanese manufacturer with a known particle distribution and known activity profile. The reason: when you're reflowing a tiny chip on a logic board, the difference between good paste and cheap paste is the difference between a clean joint and a bridge that creates an intermittent short three months later.
Cheap paste is fine if you're rebuilding a hobby motherboard. It's not fine if you're billing a customer who has a 90-day warranty on the work.
Why we test before we ship
Every device we touch goes through a final-test bench cycle before we hand it back. For a phone, that's: power cycle, full-charge cycle, every sensor checked (touch, accelerometer, ambient light, proximity, mic, speakers, both cameras), every button. For a laptop, it's that plus a memory test, a disk SMART read, and a one-hour stress cycle.
This is the slow part of the shop. It's also the part that makes the warranty mean something. If we test it and it works, and you take it home and it doesn't, the diagnosis is going to be that something happened in transit, not that we shipped you a half-fixed device.
questions about anything in this note? call (608) 467-4012.