holdfast (tool)
{{short description|Woodworking tool for securing a work-piece to a bench}}
{{Other uses|Holdfast (disambiguation)}}
{{Infobox tool|name=Holdfast|image=holdfast.jpg|other_name=Hold fast, hold-down|used_with=Woodworking workbench or anvil|types=|caption=A carpenter using a holdfast}}
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.{{cite book|last1=Bealer|first1=Alex|title=Old Ways of Working Wood: The Techniques and Tools of a Time-Honored Craft|date=1989|publisher=Bonanza Books|location=New York|isbn=0-517-69313-5|page=[https://archive.org/details/oldwaysofworking00beal/page/73 73]|url-access=registration|url=https://archive.org/details/oldwaysofworking00beal/page/73}}
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 {{Convert|3/4|in|mm|abbr=}} holes, somewhat narrower than had been traditional.{{Cite web|date=2019-04-03|title=Why a 1" Holdfast Hole?|url=https://blog.lostartpress.com/why-a-1-holdfast-hole/|access-date=2020-09-10|website=Lost Art Press|language=en-US}} 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.{{Cite book|title=The Complete woodworker|date=1980|publisher=Ten Speed Press|others=Jones, Bernard E. (Bernard Edward), 1879-1965.|isbn=0-89815-022-1|edition=New|location=Berkeley, Calif.|pages=50–52|oclc=7283260}}
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.{{Cite book|last=Schwarz|first=Christopher|url=https://lostartpress.com/collections/books/products/ingenious-mechanicks|title=Ingenious Mechanicks: Early Workbenches & Workholding|publisher=Lost Art Press LLC|year=2018|isbn=978-0-9978702-7-5|location=Fort Mitchell, Kentucky|pages=4–8, 100–110}} 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.{{Cite book|last=Moxon|first=Joseph|url=https://archive.org/details/mechanickexercis00moxo|title=Mechanick exercises, or, The doctrine of handy-works : began Jan. 1, 1677 and intended to be monthly continued|date=April 1678|publisher=Joseph Moxon, at the sign of the Atlas on Ludgate Hill|others=Boston Public Library|location=London|pages=56–61|chapter=The Art of Joynery}}{{Cite book|last=Roubo|first=M. André Jacob|url=https://archive.org/details/gri_33125009321916|title=L'art du menuisier|date=1769|publisher=Académie Royale des Sciences|others=Getty Research Institute|location=Paris|pages=32–35}} The term has been in use since at least the 16th Century.{{Cite web|date=2014-03-02|title=How do You Say 'Holdfast?'|url=https://blog.lostartpress.com/2014/03/01/how-do-you-say-holdfast/|access-date=2020-09-10|website=Lost Art Press|language=en-US}} Use declined throughout the 20th century, but has seen a resurgence in recent years.{{Cite web|date=2013-05-28|title=Holdfasts - How To Make Them Grip Like A Gorilla|url=https://www.theenglishwoodworker.com/holdfasts-get-a-grip/|access-date=2020-09-10|website=The English Woodworker|language=en-GB}}
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.).
Gallery
File:Holdfast illustration adapted from L'Art du Menuisier.png|Illustration from L'Art du Menuisier (1769) demonstrating how the holdfast is secured in the workbench hole
File:Engraving showing two putti using a Roman workbench, based on a fresco from the ruins of Herculaneum.jpg|Roman workbench with a holdfast, based on a 1st Century AD fresco from the ruins of Herculaneum
File:Cc&j-fig40--bench holdfast.png|Illustration of a screwed holdfast from Cassell's Carpentry and Joinery (1907)
File:Men veneering from L'Art Du Menuisier-Carrossier (Roubo).png|Illustration from L'Art du Menuisier (1769) showing a workbench with holdfasts in use