Before the 1970s, domestic defense production was extremely limited. Local industrial plants made items such as uniforms, storage batteries, glassware, preserved foods, some electronic devices, and certain pharmaceutical and chemical products. The production of armaments, began on a modest scale in 1969 and received increasing government assistance. In August 1976, the Ministry of Defense announced that it had invested more than US$200 million since 1969 in developing domestic production of ordnance items. This investment resulted in the local production of 5.56mm, 7.62mm, and .30 calibre ammunition. In addition, the government operated facilities for limited rebuilding and modernization of military vehicles, aircraft engines, and helicopters. A modern dockyard provided similar improvements as well as maintenance on naval vessels and their armaments. Most of these capabilities were achieved with American technical assistance.
In December 1977, Prime Minister Kriangsak announced plans to establish a number of new factories to increase the strength of the country’s arms industry. In particular, he hoped to meet internal security requirements for ammunition and light weapons. The industrial expansion called for private as well as government-owned facilities. The primary vehicle for this was a privately owned company called Thai Interarms, which received substantial government aid. Divided into four subunits, the company manufactured small arms, ammunition, gunpowder, and other explosives. In addition, a factory established in Ta Khli, a joint venture between the Thai government and the Winchester Company of the United States, had a projected production capability of 1 million tons of ammunition annually, including rockets.
To strengthen the navy’s combat readiness, the government expanded its naval repair facilities with aid from the United States, Italy, and Japan. As a result, Thailand produced a variety of naval vessels, including six fast coastal patrol boats, and had an LST (landing ship, tank) under construction in 1987. Despite the ambitious scope of plans for a domestic defense industry, however, production failed to reach the levels desired.