Two demo repairs

The phone battery swap is for a glued 6.1-inch phone: 16 steps, about 50 minutes, difficulty 3 of 5. Two pentalobe screws at the charging port, heat to soften the glue, a suction cup and picks, the display opened like a book to the right, two small brackets, two adhesive pull strips, then everything back in reverse.

The laptop RAM upgrade is for a 14-inch laptop: 12 steps, about 35 minutes, difficulty 2 of 5. Eight cover screws of two lengths, a spudger around the seam, the battery unplugged first, the clips pushed outward so the memory module pops up to 30 degrees, and the new one in the same way.

Both are generic demos that we wrote, not any maker's guide. They play on a bench instead of a floor: a small mat with a fine grid, a 24 mm coin and a 10 cm ruler on the stage for scale, and every size under a centimetre in millimetres.

The gate, and why it is modal

Before step 1 of a repair comes a screen titled "Before you open it." It is a short list you tick line by line as you do each thing. Behind it the first step does not play, the controls do nothing, keys do nothing, and on a phone it fills the screen. The button reads "2 of 5 done" until every line is ticked, and "Not today" takes you back out.

We made it modal because a warning you can dismiss gets dismissed. On a bookcase a skipped warning costs an evening. On a phone it can cost the phone, or start a fire. The co-pilot's line on that screen:

"Tick each one as you do it. Skipping these is how a repair becomes a replacement."

The phone's list, in full:

  1. Power the phone off, then drain the battery below 25 percent before you start. A punctured full cell catches fire; a low one smokes.
  2. Work on a clear, hard, well-lit surface. Every screw goes into its own cell of the screw map: two lengths look the same and a long one in the wrong hole drills through the board.
  3. Cracked glass: tape over the cracks and wear safety glasses before you heat or pull.
  4. Never pry under the middle of the battery, never bend it. If it is swollen, stop here and take it to a shop.
  5. Touch bare metal before you reach inside. Lift every connector straight up with the spudger; never pull a cable.

The order is the safety

In both repairs the battery comes off before anything else and goes back last. Inside the phone, the battery connector bracket comes off first, with its two 1.2 mm screws, and the battery connector lifts straight off its socket in step 8, before either display connector is touched. On the way back the display connects first (step 14) and the battery last (step 15). The warning on that step is blunt: reversing the order is how boards get shorted on the way back together.

The laptop does the same at its own scale. The battery is unplugged in step 5, before the memory clips, and plugged back in at step 10, after both clips have clicked.

Screw lengths and the screw map

The phone has seven screws: two pentalobe screws at the bottom edge, four 1.2 mm Phillips screws and one 1.6 mm. The long one goes in the front hole of the display bracket only. The manual says why: a long screw in a short hole is the most common way a phone dies on this bench.

So the 3D has a screw map: a tray beside the phone with one cell per screw, filled in the order the screws come out and labelled by step. When a later step puts a screw back, it takes it from its cell. The laptop's tray holds eight: six 6 mm cover screws and two shorter 4 mm screws at the hinge, because a 6 mm screw at the hinge pushes through the keyboard deck.

Depth, heat and stop signs

  • Depth. Picks go in shallow. Deeper than 3 mm along the right edge cuts the display cables, so the 3D draws the pick's path where it should run, not around the whole phone.
  • Heat. About two minutes on the bottom third of the glass: hot to the touch, not too hot to hold. If you cannot keep a finger on it for three seconds, let it cool.
  • Stop signs. A swollen battery, a bulging back or a lifted glass edge means stop. That phone goes to a shop, not on this bench.

What BuildMog will not guide

Gas, mains wiring, refrigerant, brakes and airbags stay with the pros, and Mog says so. Fix mode starts with a short list of low-risk jobs: filters, descaling, resets and error codes. And no manual replaces a shop when the battery is swollen, the board has been in water, or the back glass is cracked badly enough to need a laser.

Before device repairs go beyond these two demos, the guides need sources we are allowed to use: your own manual and photos, makers' self-repair manuals with credit, or guides we write from the facts and label as unchecked until a person has finished one. That policy is still under review, so for now the two demos are where we test the engine.