Holdfast
A carpenter using a holdfast
Other namesHold fast, hold-down
Used withWoodworking workbench or anvil

A holdfast or hold fast is a form of temporary clamp used to hold a workpiece firmly to the top or side of a wooden workbench or the top of an anvil.[1]

A form of bench dog, a traditional holdfast has either a curved or flat top. Its shank is slid loosely into a “dog” hole in the bench or anvil until the tip of its hook touches the work. It is set by hitting its top with a mallet or hammer, which causes the shaft to wedge tightly against the sides of the hole. A tap of its back side near the top releases it.

Contemporary holdfasts are commonly designed to fit in 3⁄4 inch (19 mm) holes, somewhat narrower than had been traditional.[2] Scrap pieces of wood or leather are often used between the holdfast and the workpiece to prevent marring it.

An adaptation of the holdfast is threaded, sometimes known as a “screwdown”, which is tightened rather than tapped in place.[3]

History

Based on a fresco discovered in the ruins of Herculaneum, holdfasts are known to have been in use since at least the 1st century AD.[4] They are also described and illustrated in early European books on woodworking, such as Joseph Moxon's 1678 edition of Mechanick Exercises and André Jacob Roubo's 1774 L'Art du Menuisier.[5][6] The term has been in use since at least the 16th Century.[7] Use declined throughout the 20th century, but has seen a resurgence in recent years.[8]

While "artisan" holdfasts continue to be made as castings, or forgings, modern holdfasts are made from round mild steel bar stock using highly automated cold-working machines. Gramercy Tools makes such holdfasts from bar stock which is slightly under 3/4" (19.05mm) dia., usually 19mm for use in the now customary 3/4" bench holdfast holes. The making of such a holdfast is more particularly described in Gramercy Tools' patent document (U.S. Patent 7,571,631, to Moskowitz, et. al.).

See also

References

  1. ↑ Bealer, Alex (1989). Old Ways of Working Wood: The Techniques and Tools of a Time-Honored Craft. New York: Bonanza Books. p. 73. ISBN 0-517-69313-5.
  2. ↑ "Why a 1" Holdfast Hole?". Lost Art Press. 2019-04-03. Retrieved 2020-09-10.
  3. ↑ The Complete woodworker. Jones, Bernard E. (Bernard Edward), 1879-1965. (New ed.). Berkeley, Calif.: Ten Speed Press. 1980. pp. 50–52. ISBN 0-89815-022-1. OCLC 7283260.{{cite book}}: CS1 maint: others (link)
  4. ↑ Schwarz, Christopher (2018). Ingenious Mechanicks: Early Workbenches & Workholding. Fort Mitchell, Kentucky: Lost Art Press LLC. pp. 4–8, 100–110. ISBN 978-0-9978702-7-5.
  5. ↑ Moxon, Joseph (April 1678). "The Art of Joynery". Mechanick exercises, or, The doctrine of handy-works : began Jan. 1, 1677 and intended to be monthly continued. Boston Public Library. London: Joseph Moxon, at the sign of the Atlas on Ludgate Hill. pp. 56–61.
  6. ↑ Roubo, M. André Jacob (1769). L'art du menuisier. Getty Research Institute. Paris: Académie Royale des Sciences. pp. 32–35.
  7. ↑ "How do You Say 'Holdfast?'". Lost Art Press. 2014-03-02. Retrieved 2020-09-10.
  8. ↑ "Holdfasts - How To Make Them Grip Like A Gorilla". The English Woodworker. 2013-05-28. Retrieved 2020-09-10.


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