by Greg Whiter, VK
4IG (Ex VK3CA)

These pages depict Clark Masts original range of mast products.
To see Clark's current mast series go to Portable Mast Australia Pty Ltd's (PMA's) web site.


Page 4 of 18 - Clark Masts, over 67 Years Old in 2023 - WT Mast Series

In the early 1970's Clark Masts published their first catalogue in 16 years. Alec Clark, the company's founder had been designing and building portable air-operated telescopic masts since 1957. During this time Alec Clark's unique lightweight portable masts had found their way into applications throughout the world with government Departments Of Defence, Police Departments, Fire Departments and Emergency Services. Commercial and industrial applications included for Radio Field Strength Surveying, TV Field Strength Surveying and portable radio communications. 

Alec Clark's company, Clark Masts Limited, performed practically ever manufacturing operation itself in-house. Fabrication, casting, precision machining, canvas sewing, plastic and rubber mouldings, anodising and plating, painting, printing, publishing and even the manufacture of packing cases were all in-house operations. 

Australian users first saw these unique portable masts in the early 1960's courtesy of a antenna manufacturing company called Belling-Lee and the foresight of a gentleman working for them at the time, Frank Welsh. Frank went on, with others, to form his own company, Scalar Industries, in the late 1960's and brought the Clark Masts agency with him. Following Frank Welsh's retirement from Scalar in the mid 1980's
GFS Electronics took on the Australian distributorship and continued to market Clark Masts in the Australia Asia-Pacific region until the company was closed in 2011. In 2012 a new company, started by Greg Whiter, who was previously Managing Director of GFS Electronics took over the Australian distributorship of Clark Masts. That new company is Portable Masts Australia Pty Ltd.

Illustrated in this web page, for historical purposes, are the WT Series Masts pages from Clark Masts early 1970's catalogue.


Clark Masts early 1970's WT mast seriesWT Series air-operated masts

The Clark Masts WT mast series of the late 1960's - early 1970's was their heaviest duty series, consisting of 11 different models, all with keyed sections to prevent inter-section rotation, making WT masts suitable for use with directional headloads. This early WT Series of masts was available in heights of 3.2 to 30.5 metres with headload capabilities from 11.2 to 136 Kg. Today's WT Series of masts includes a total of 140 models with heights from 3.47 to 30.57 metres and a headload capability from 12 to 120 Kg.

Clark Masts early 1970's WT mast series

As can be seen from above, WT Series masts were particularly designed to be internally vehicle mounted where heavy loads were required to be lifted up to 30 metres. Battery powered Air Source/Mast Controllers provided mast extension/retraction control. A Tripod field mounting option was also available for the WT Series as was a handpump for manual extension.

Clark Masts Early WT Series Table Of Models

From the table above it can be seen that Clark Masts early WT mast series were capable of operating, unguyed with 1000 square cm of sail area on top into wind, in wind speeds from 40 to 160 km/hr. If guyed WT models were rated from 80 to 160 km/hr. All WT Series masts had base tube diameters of 152.4 mm (6"), 38.1 mm (1.5") larger than the PT Series base tubes. Unlike the PT Series, all masts in the WT series (except the WT8) had 40 mm sockets at their head with a quick clamp for attachment of their headload. The WT8 retained a 24 mm socket like the PT, ST and QT series.

WT Series AccessoriesClark Masts WT mast series Accessories

A range of accessories was available for the WT mast series which included mounting brackets for internal and external vehicle mounting, guy collars and guy assemblies as well as guy pickets etc.

CLARK SCAMP MOPED - A slight diversion from portable mast manufacturing occurred for Alec Clark in 1967 with the design and manufacture of a small moped called the Clark "Scamp". The Scamp was developed and marketed in the United Kingdom by Alec's company AN Clark (Engineers) Limited from March to November 1968. For more details on the Clark Scamp moped see HERE.

Next Page - Clark Masts History - Page 5 - DAF Series

Other Web Articles by the same author   EARLY YAESU MUSEN EQUIPMENT IN AUSTRALIA 


Links to other pages in this article
Page 1 Clark Masts History - Early 1970's QT Mast Series
Page 2 Clark Masts History - Early 1970's ST Mast Series
Page 3 Clark Masts History - Early 1970's PT Mast Series
Page 4 Clark Masts History - Early 1970's WT Mast Series
Page 5 Clark Masts History - Early 1970's DAF Mast Series
Page 6 Clark Masts History - Early 1970's SCAM Mast Series
Page 7 Clark Masts History - Early 1970's PB1 Mast
Page 8 Clark Masts History - Early 1970's Surveyor Mast Series
Page 9 Clark Masts History - Early 1970's 63/70 Trailer Mounted Mast
Page 10 Clark Masts History - Early 1970's 63/100 Trailer Mounted Mast
Page 11 Clark Masts History - Early 1970's Mast Fitting and Mountings
Page 12 Clark Masts History - Early 1970's Vehicle Mounting Accessories
Page 13 Clark Masts History - Early 1970's Air Supply Equipment
Page 14 Clark Masts History - Early 1970's Guying Equipment
Page 15 Clark Masts History - Early 1970's Antenna Fittings
Page 16 Clark Masts History - Early 1970's Miscellaneous Equipment
Page 17 Clark Masts History - Early 1970's Antenna Mounting
Page 18 Clark Masts History - Early 1970's Useful Wind Information
Appendix Clark Masts History - The 1968 Clark Scamp Moped

Any comments on this article should be directed to the author, Greg Whiter at: 


Details On Clark Masts Current Range Of Portable Telescopic Pneumatic Mast Products 

This page is sponsored by Portable Masts Australia Pty Ltd
Suppliers of Fast Erecting air operated telescopic portable masts and towers as well as Debeglass Non-Conductive Guy Wire
For product details and a catalogue covering over 200 different mast types of Clark Masts go to
PMA's web site.
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Phone: +61 402130692
Mob: 0402130692
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This page was last updated 05-01-2023

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