Borders and edges lose gloss first, and the reason is geometric, not chemical. A 700 mm planetary head cannot reach the last 50 mm, so that strip never receives the same passes, pressure or water as the field. It dries out, it hazes, and under grazing light it reads as a dirty frame around a clean floor.

Why the edge falls behind

Cause	What happens	Fix
Head cannot reach	Last 30-60 mm gets fewer passes	Hand tool or edge machine at each grit
Dry edge	No water reaches, segment glazes	Hand water bottle or wet sponge
Overpressure by hand	Dished edge, ring of different gloss	Light pressure, machine weight
Skip at final grit	Edge stays at 800 while field is 2000	Run every grit at the edge, no exceptions
Grout or skirting shadow	Dirt line reads as gloss loss	Detail clean before buffing

Edge sequence that matches the field

1. Cut the edge with an edge tool or hand grinder at the same grit the field is on, before moving the main machine.
2. Keep water on the edge; a dry edge segment glazes in seconds and then polishes nothing.
3. Work the edge 150-200 mm wide so it overlaps the field pass and the transition is invisible.
4. Repeat at every grit, including the densifier stage and the final polish. The edge is not a separate job at the end.
5. Buff the edge by hand with the same pad and a light touch, then compare under a raking light from two directions.

Blending the transition

• Overlap the edge pass 100 mm into the field so the two gloss levels meet gradually.
• Never polish the field first and the edge last at a different grit; that is how a visible frame appears.
• On borders with a colour change, blend on the darker side; light edges show gloss differences more.
• Check the reflection of a straight object along the border. A wavering line means the edge is dished.

Hand polishing without dishing

Use the tool's weight, not your arms. Keep the pad flat, move in overlapping arcs, and stop before the edge gets hot. Two light passes beat one heavy pass every time, and a dished edge needs a full re-hone to correct, which costs more than the hand work saved.

Price the edge as a line item per linear metre. It is the slowest part of the floor and the part the client inspects first.