Felt is older than weaving. Matted wool needs no loom — only fibre, moisture, heat and agitation. Wool fibres are covered in microscopic scales; work them together wet and warm and the scales interlock and ratchet, and the mat never comes apart. That makes felt one of the oldest textiles humans have, and it is why a felt hat can be one continuous piece with no seam anywhere.

Why steam and not just water. Steam carries far more energy than hot water at the same temperature and penetrates the mat faster and more evenly. It swells and relaxes the fibre scales so they slide instead of gripping — which is exactly the opposite of the felting process that made the material. When the hat dries, the scales lock again in the new shape. Milliners have kept steaming rather than soaking for a reason: the search literature is blunt that steaming is the old way and works best.

The block is the pattern. There is no paper pattern in blocking. The wooden block is the design, which is why milliners accumulate and guard collections of blocks, and why block-makers were a specialist trade. A hat shape going out of fashion meant a block going idle for thirty years — and blocks were kept, because fashion returns.

Stiffener. Commercial hoods and capelines arrive pre-stiffened, traditionally with shellac, which is what lets the blocked shape hold. Some milliners add more stiffener for a crisper result; a common modern workshop substitute is a 50/50 mix of PVA and water, chosen because it does not dry to a white film. Both are legitimate; the shellac route is the historical one.

The hatter's disease — and why this blueprint is safe. Historic fur felting, not wool, used mercury nitrate to make animal fur mat properly. The mercury poisoned generations of hatters, causing the tremors and neurological damage behind the phrase "mad as a hatter". That process is long abandoned and it is not this one: wool felts through mechanical agitation alone and needs no mercury or any other toxic agent. The history is worth knowing precisely because the modern craft carries none of it.

Millinery

Blueprints (1)

Blocking a Felt Hat