How to fabricate traffic signs correctly with the SIGNFIX System
The Signfix spacing charts were developed from structural calculations and testing of Signfix extrusion designs to ensure compliance with current wind load requirements. The summary should not be extended to extrusions of alternative manufacture as they display different structural properties and deflection characteristics. These charts are calculated around values based on the use of 2mm aluminium 5251 H34 sheet. They should not be applied to sign panels fabricated from alternative gauge, composition of aluminium or steel or plastic substrates.
Wind speed = 50m/sec AS/NZS1170
The charts are applicable to SIGNFIX Small Channel, Medium Channel, \'Interlink\' and \'Dovetail\' extrusions. Although reference is made to post spacings, these charts do not provide guidance on the selection of the correct number, size or specification of posts. This should be the subject of separate structural calculations. (Please contact Signfix Systems Ltd for further advice or refer to Pole Selection Formula under Important Technical Information). 

To determine the correct channel type and centre spacing of standard regulatory or warning signs please download a copy of the Signfix Centre Spacing Chart HERE. 

Small Single Plate Sign Panel - On One Post
On single post installations do not exceed the maximum sign width of 0.9m (Small Channel) or 1.3m (Medium Channel)

Single Plate Sign Panel - Medium Channel on Two or Three Posts
CALCULATING MAXIMUM CHANNEL SPACINGS FROM KNOWN POST CENTRES
1.Refer to Table B. Determine the maximum post centres and take note of the corresponding maximum channel  spacing value.
2.Refer to Table C. Determine the maximum overhang and take note of the corresponding maximum channel spacing value.
3.Compare the channel spacing values you have calculated from Tables B and C.
CALCULATING MAXIMUM POST CENTRES FROM KNOWN CHANNEL SPACINGS
Tables B and C may be used in reverse to determine whether post centres exceed requirements for known channel spacings.

Example: Two posts, medium channel, single plate: if B = 1 .6m andib maximum dimension of C = 0.5m. From Table B and C: the MAXIMUM spacing between channel = 0.4

Modular, Multiple Panel Assemblies - Two or More Posts
CALCULATING MAXIMUM CHANNEL SPACINGS FROM KNOWN POST CENTRES
1. Refer to Table D. Determine the maximum post centres and take note of the corresponding maximum channel spacing value.
2. Refer to Table E. Determine the maximum overhang and take note of the corresponding maximum channel spacing value.
3. Compare the channel spacing values you have calculated from Tables D and E.
4. Adopt the worst case (lowest) reading of the two as the guide of the channel spacings to be adopted.
CALCULATING MAXIMUM POST CENTRES FROM KNOWN CHANNEL SPACINGS
Tables D and E may be used in reverse to determine whether post centres exceed requirements for known channel spacings.