What is a 90-degree parting tool used for?

It cuts a narrow V-shaped groove, useful for outlining, separating details and cleaning up tight corners. In this micro set the widths suit eyes, hair, fur and feather texture on small carvings.

Is this set worth it over buying single tools?

If you need several fine widths, the four-piece set covers 1.5mm to 4mm in one purchase. Buyers who only need one width can often spend less on a single Flexcut micro tool.

How does it compare with Flexcut's larger carving sets?

This is a detail set, not a full carving kit. The blades are much narrower than standard gouges and are meant for finishing and texture, not roughing out stock.

Do the blades need sharpening out of the box?

Flexcut hand-hones and polishes the edges, so they should cut as shipped. Touch up with a slip strop and honing compound as the edge dulls.

Four tools: MT39 (1.5mm), MT40 (2mm), MT41 (3mm) and MT42 (4mm), each with an ash handle. No case or sharpening accessories are included.

How do I keep the ash handles in good shape?

Wipe them clean and oil them occasionally with a light wood finish to keep them from drying and cracking. Store the tools so the thin blades are not knocked against each other.