Local communities in the Tapajós National Forest are positive about logging but should be more involved in both management and the sharing of benefits

A machinist achieves that geometric precision by using tools that come with a feature called the chamfer, which cuts a 90-degree angle or edge to make it more symmetrical. This gradual cutting motion allows a tap to smoothly enter a hole.

The ITTO Tropical Forest Update is published quarterly in English, French and Spanish. The French and Spanish editions are usually posted about one month after the English.

A series of ITTO projects have helped strengthen forest statistics in Gabon, but the full implementation of a national system requires more support from government

A study finds that some basic work is being done in Asia to improve teak growing stock, but not yet at a scale to impact timber production

Reports on the 39th Session of the International Tropical Timber Council and the 6th Session of the United Nations Forum on Forests

Unlike cutting taps, forming taps create external threads. Forming taps involves the displacement of a material (like metal) within a hole. Additionally, forming taps usually require a larger hole because this style causes a material to thread away and into the threads of the tap.

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Sustainable forest management (SFM) has always been a goal of foresters. The trouble is, the concept of SFM has changed. Once, foresters learned mainly about sustained timber yield—how to calculate it, measure it and achieve it in the forest. Now, the profession has many more concerns: biodiversity conservation, community involvement, and a rapidly changing marketplace, to name only a few. In the tropics, the forestry profession is beset with problems ranging from illegal harvesting and disputed land tenure to the high profitability of alternative land-uses and competition in international timber markets. Given the changing nature of the challenges facing SFM in the tropics, international treaties set up to meet them must also evolve.

Cutting taps and forming taps both have benefits and limitations from stronger threads to greater compatibility. But it’s the machinist who decides which tapping style to use depending on the job at hand.

Cutting taps and forming taps produce threads that are interchangeable and gauge identically, but those are the only similarities between the two tapping styles.

When machinists need to create internal threads, they opt for cutting taps. Cutting a tap means using tools that remove material from the tapped hole, according to North American Tool. This process then leaves an internal thread that meets the machinist’s desires.

The two threading methods tap holes differently, but they also have a handful of other differences, starting with the type of thread each method produces.

The projects summarised here were financed at the 39th session of the International Tropical Timber Council in November 2005

Cutting taps also have the upperhand regarding horsepower, as this threading method requires less power than forming taps.

Formed threads are stronger because the grain flow of materials is compressed at the crest and root of the thread form. Compare that to cut threads, which because of the tools used, cause grain structure to essentially fracture.

Cutting taps are more versatile than forming taps and can be used with more materials. When machinists use forming taps, they can only use the process on aluminum, soft steel and nonferrous metals. But machinists aren’t limited to the materials when they decide to cut taps.