Semicircle Steel Plates – Half Moon Mild & Stainless Plates

Flat semicircle (half-moon) steel plates, plasma cut from 3, 4 or 5 mm mild steel, 304 or 316 stainless. Sizes run from 200 mm to 1000 mm across the straight edge.

At a glance

• Shape: half circle, one straight edge and one curved edge, no holes
• Diameters: 200, 300, 400, 500, 600, 800 or 1000 mm (the depth is half the diameter)
• Thickness: 3 mm as standard, 4 mm and 5 mm cost more
• Material: mild steel, 304 or 316 stainless
• Finish: plasma-cut edge, deburred, mill finish (unpainted)
• Made in Knowsley, Merseyside

Need a quarter circle, a segment or another size? Send us a drawing.

Common uses

Half-moon plates are used as hearth and doorstep plates, wall-mounted shelf and bracket blanks, gate and fence toppers, table ends, planter bases and gussets on round tanks. The size is the diameter, which is the length of the straight edge. A 600 mm plate is 600 mm wide and 300 mm deep.

Choose your material

• Mild steel: the economical choice. Paint, prime or galvanise it for outdoor use.
• 304 stainless: the everyday stainless grade for indoor and sheltered outdoor use.
• 316 stainless: best near the coast, pools, salt or chemicals. 304 vs 316 explained.

How to order

1. Pick your material and thickness.
2. Pick the diameter.
3. We plasma cut, deburr and pack your order.
4. Delivery is added at checkout.

Made to order. We email your dispatch date. See delivery rates. Full discs: circular plate. Stove plates: hearth plates.

Questions

How deep is an 800 mm semicircle?
400 mm from the straight edge to the top of the curve.

How much does a 600 mm plate weigh?
About 3.3 kg in 3 mm mild steel.

Are these laser cut?
No. They are plasma cut and deburred, so edges show a plasma-cut finish and are not held to laser-cut tolerances. For tight-tolerance parts, send us a drawing.