Build guide: press every magnet flush with parallel pliers

src/content/docs/build/index.mdx

@@ -109,7 +109,7 @@ Static can damage the PCBAs.
 - A 3D printer with a 0.4 mm nozzle, or access to one (for example, at a library or makerspace). We recommend Bambu printers, but anything from a Prusa MK3S up can do the job.
 - At least one full spool of filament. Black PLA is the basic choice. Any filament that isn't opaque to infrared light at 940 nm needs [silver Sharpie](https://www.amazon.com/Sharpie-39108PP-Metallic-Permanent-Blister/dp/B00009RAX4) on the key flags ([Step 5](/build/#step-5-ink-the-key-flags)). Only Sharpie-brand silver works reliably. Sharpie gold, bronze and copper are less reliable.
 - [Medium CA glue, with fine applicator tips](https://a.co/d/0MWOtlK).
-- Adjustable parallel pliers. We recommend the [Knipex Pliers Wrench, 180 mm](https://www.amazon.com/dp/B081K8WFTF).
+- Adjustable parallel pliers. We recommend the [Knipex Pliers Wrench, 180 mm](https://www.amazon.com/dp/B081K8WFTF). These are required for pressing magnets fully flush.
 - A small flat-blade screwdriver, about 4 mm wide and 1 mm thick.
 - A heat set insert kit or a soldering iron, for example [this one](https://amzn.to/3TOY4MW).
 - 3D printing experience. This is an advanced build. Depending on your filament and your printer, you may need to tune your slicer settings to get working parts.
@@ -433,6 +433,8 @@ Each finger cluster has 5 keys, so a finished cluster with its keys needs 10 mag
 
 All magnets are 2.0 mm x 1.5 mm N35.
 
+**Press every magnet fully flush.** The fit between keys and clusters has little room to spare, and a proud magnet uses some of it up.
+
 - **Clusters:** the **north** pole faces out.
 - **Keys:** the **south** pole faces out, so it's the visible side.
 
@@ -444,7 +446,7 @@ All magnets are 2.0 mm x 1.5 mm N35.
 4. Pick up a magnet with a thin flat-blade screwdriver.
 5. Dip the magnet in the glue.
 6. Press it into the hole in the key.
-7. Squeeze the magnet flush with parallel pliers.
+7. Squeeze the magnet flush with parallel pliers, every time, even when it already looks flush.
 8. Let the glue cure before you use the key.
 
 <CadFigure name="cad-magnet-flush" alt="Two cut-away views of a key with its magnet. Before: the magnet stands proud of the key between the open jaws of parallel pliers. After: the jaws are closed and the magnet is flush." caption="Squeeze the magnet flush with parallel pliers." />
@@ -456,17 +458,22 @@ All magnets are 2.0 mm x 1.5 mm N35.
 3. Put glue in the magnet holes of the keys.
 4. Pick up a magnet with a thin flat-blade screwdriver.
 5. Press it into the hole in the key.
-6. Squeeze the magnet flush with parallel pliers.
+6. Squeeze the magnet flush with parallel pliers, every time, even when it already looks flush.
 7. Let the glue cure.
 
 ### Cluster magnets
 
-Install the cluster magnets the same way, from the Cluster stage (north pole up). Orange rings mark each magnet.
+Install the cluster magnets the same way, from the Cluster stage (north pole up). Press the side key magnets in with the screwdriver first, then finish with the pliers: put the jaw tips into two opposite key wells and squeeze to push both magnets flush. Orange rings mark each magnet.
 
 <CadFigure name="cad-magnets-finger-cluster" alt="A finger cluster from above and the same cluster turned over. Orange rings mark the five magnets: one in the wall of each side key slot, and the center key magnet on the underside." caption="Finger cluster magnets: one in each side key slot, one for the center key on the underside." />
 
 <CadFigure name="cad-magnets-thumb-cluster" alt="A right thumb cluster from above. Orange rings mark the five magnets: Nail, Knuckle, Pad, Up and Down." caption="Thumb cluster magnets (right cluster shown; the left cluster is the mirror image)." />
 
+<CadFigure name="cad-magnet-screwdriver-slot" alt="A finger cluster with a flat-blade screwdriver in the East key slot. The flat of the blade is on the magnet, and an arrow shows it pressed toward the slot wall." caption="Press each side key magnet into its hole with the screwdriver first." />
+
+<CadFigure name="cad-magnet-pliers-tips" alt="A cross-section of a finger cluster through its East and West key wells, with a pliers jaw tip down in each well. Before: the magnet in the inner wall of each well stands slightly proud, each jaw rests on its magnet, and arrows show the jaws closing toward the center. After: both magnets are flush. The curved backs of the jaw tips pass over the outer walls of the wells." caption="Jaw tips in opposite key wells: squeeze to push both magnets flush." />
+
+
 ### Key magnets
 
 <CadFigure name="cad-magnets-keys" alt="The keys in a row, each with its magnet in orange and ringed: North, side, tipping center, Nail, Knuckle, Pad, Up, the curved Up, and Down." caption="Where the magnet goes in each key. The south pole faces out." />
@@ -494,9 +501,9 @@ Each cluster takes a square nut in the back of its underside, the fixing point f
 
 ### Insert the keys
 
-Every key should slide easily into place and snap to its magnet.
+Press each key into its slot until it snaps to its magnet. It takes a little force to go in, and then it moves freely.
 
-<CadFigure name="cad-key-insert" alt="A finger cluster with its keys in place except the East key (orange), which is above its slot with an arrow pointing straight down." caption="Slide each key straight down into its slot until it snaps to its magnet." />
+<CadFigure name="cad-key-insert" alt="A finger cluster with its keys in place except the East key (orange), which is above its slot with an arrow pointing straight down." caption="Press each key straight down into its slot until it snaps to its magnet." />
 
 If a key doesn't slide in easily or doesn't move freely: