Monday, 15 February 2010

Mesh Sizes

Mesh and grit sizes are most often refered to by a number. This relates to the number of wires per inch - and in a subsidary fashion also to the size of the wire used to form the grid through which the material falls and so is sorted into various sizes. The table below gives some of these figures most useful for mould making - mesh number, percentage of open area, the wire diameters in mm, and the mesh opening or material size in mm.

No.12 ; % open 51.8 ; dia. 0.5842 ; size 1.5240

No.14 ; % open 51.0 ;dia. 0.5080 ; size 1.2954

No.20 ; % open 46.2 ; dia. 0.4064 ; size 0.8636

No.30 ; % open 37.1 ; dia. 0.3048 ; size 0.5156

No.40 ; % open 36.0 ; dia. 0.2286 ; size 0.3810

No.50 ; % open 30.3 ; dia. 0.1905 ; size 0.2794

No.60 ; % open 30.5 ; dia. 0.1397 ; size 0.2337

No.80 ; % open 31.4 ; dia. 0.1143 ; size 0.1778

No.100;% open 30.3 ; dia. 0.0940 ; size 0.1397

No.120; % open 30.7 ; dia. 0.0940 ; size 0.1168

No.200; % open 33.6 ; dia. 0.0533 ; size 0.0737

No.325;% open 30.0 ; dia. 0.0356 ; size 0.0432