mortise and tenon#Types

A mortise and tenon (occasionally mortice and tenon) joint connects two pieces of wood or other material. Woodworkers around the world have used it for thousands of years to join pieces of wood, mainly when the adjoining pieces connect at right angles though it can be used to connect two work pieces at any angle.

Mortise and tenon joints are strong and stable joints that can be used in many projects and which gives an attractive look. They connect by either gluing or friction-fitting into place. This joint is difficult to make, because of the precise measuring and tight cutting required; as such, modern woodworkers often use machinery specifically designed to cut mortises and matching tenons quicker and easier. Many woodworkers prefer to cut these by hand in a traditional manner. In its most basic form, a mortise and tenon joint is both simple and strong. There are many variations of this type of joint, and the basic mortise and tenon has two components:

the mortise hole, and
the tenon tongue.

The tenon, formed on the end of a member generally referred to as a rail, fits into a square or rectangular hole cut into the other, corresponding member. The tenon is cut to fit the mortise hole exactly. It usually has shoulders that seat when the joint fully enters the mortise hole. The joint may be glued, pinned, or wedged to lock it in place.

This joint is also used with other materials. For example, it is traditionally used by both stonemasons and blacksmiths.

Etymology

The noun mortise, "a hole or groove in which something is fitted to form a joint", comes from {{c.|1400}} from Old French {{lang|fro|'mortaise'}} (13th century), possibly from Arabic {{transl|ar|'murtazz'}}, "fastened", past participle of {{transl|ar|'razza'}}, "cut a mortise in".{{OEtymD|mortise|access-date=2019-02-19}} The word tenon, a noun in English since the late 14th century, developed its sense of "a projection inserted to make a joint" from the Old French {{lang|fro|'tenir'}} "to hold".{{OEtymD|tenon|access-date=2019-02-19}}

History and ancient examples

File:Stool with woven seat MET 14.10.3 view 4.jpg

The mortise and tenon joint is an ancient joint. One of the earliest mortise-tenon structure examples dates back 7,000 years to the Hemudu culture in China's Zhejiang Province.{{Cite web |title=Across China: Ancient woodworking technique revived in modern times - Xinhua {{!}} English.news.cn |url=http://www.xinhuanet.com/english/2018-07/02/c_137296144.htm |access-date=2024-03-26 |website=www.xinhuanet.com}} Tusked joints were found in a well near Leipzig,{{cite web | url=http://www.archaeology.org/issues/152-1411/features/2591-germany-recreating-neolithic-toolkit | title=The Neolithic Toolkit | publisher=Archaeology.org | access-date=7 January 2015}} created by early Neolithic Linear Pottery culture, and used in construction of the wooden lining of the wells.[http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0051374 Early Neolithic Water Wells Reveal the World's Oldest Wood Architecture] Tegel W, Elburg R, Hakelberg D, Stäuble H, Büntgen U (2012) Early Neolithic Water Wells Reveal the World's Oldest Wood Architecture. PLoS ONE 7(12): e51374. doi:10.1371/journal.pone.0051374 Mortise and tenon joints have also been found joining the wooden planks of the "Khufu ship",Ward, Cheryl. "[http://www.archaeology.org/0105/abstracts/abydos3.html World's Oldest Planked Boats]," in Archaeology (Volume 54, Number 3, May/June 2001). Archaeological Institute of America. a {{cvt|43.6|m}} long vessel sealed into a pit in the Giza pyramid complex of the Fourth Dynasty around 2500 BC. They were also found in the Uluburun shipwreck (14th century BC).{{cite journal |last1=Pulak |first1=Cemal |year=1998 |title=The Uluburun Shipwreck: An Overview |journal=The International Journal of Nautical Archaeology |volume=27 |issue=3| pages=210 |doi=10.1111/j.1095-9270.1998.tb00803.x |quote=Pegged mortise-and-tenon joints similar to those used in Graeco-Roman ships of later centuries fasten its planks together and to the keel.}}

File:Mortise_tenon_joint_hull_trireme-en.svg

Mortise and tenon joints have also been found in ancient furniture from archaeological sites in the Middle East, Europe and Asia. Many instances are found, for example, in ruins of houses in the Silk Road kingdom of Cadota, dating from the first to the 4th century BC.{{cite journal|last=Roberts|first=Rachel|title=House-building in Ancient Niya|journal=IDP News|year=2012|volume=39|url=http://idp.bl.uk/archives/news39/idpnews_39.a4d#3|access-date=26 October 2012}} In traditional Chinese architecture, wood components such as beams, brackets, roof frames, and struts were made to interlock with perfect fit, without using fasteners or glues, enabling the wood to expand and contract according to humidity.{{cite book

| first= Nancy W.

| last= Steinhardt

| year= 2002

| title= Chinese Architecture

| edition= English

| publisher= Yale University Press

| pages= [https://archive.org/details/chinesearchitect0000unse/page/1 1]

| isbn= 978-0-300-09559-3

| url= https://archive.org/details/chinesearchitect0000unse/page/1

}} Archaeological evidence from Chinese sites shows that, by the end of the Neolithic, mortise and tenon joinery was employed in Chinese construction.{{cite book

| first= Liu

| last= Xujie

| year= 2002

| title= Chinese Architecture - The Origins of Chinese Architecture

| edition= English

| publisher= Yale University Press

| pages= [https://archive.org/details/chinesearchitect0000unse/page/11 11]

| isbn= 978-0-300-09559-3

| url= https://archive.org/details/chinesearchitect0000unse/page/11

}}

The thirty sarsen stones of Stonehenge were dressed and fashioned with mortise and tenon joints before they were erected between 2600 and 2400 BC.{{Cite web|title=Building Stonehenge|url=https://www.english-heritage.org.uk/visit/places/stonehenge/history-and-stories/building-stonehenge/|access-date=2020-10-27|website=English Heritage}}

A variation of the mortise and tenon technique, called Phoenician joints (from the Latin {{lang|la|coagmenta punicana}}){{Cite book|last=Cato|first=Marcus|url=https://www.loebclassics.com/view/cato-agriculture/1934/pb_LCL283.35.xml|title=De agri cultura|publisher=Loeb Classical Library|year=1934|editor-last=|editor-first=|language=la|translator-last=Henderson|translator-first=Jeffrey|trans-title=On agriculture|chapter=XVIII|author-link=Cato the Elder|access-date=2021-04-27|orig-year={{c.|160 BC}}}}{{Cite journal|last=Sleeswyk|first=A. W.|date=1980-08-01|title=Phoenician joints, coagmenta punicana|url=https://www.tandfonline.com/doi/abs/10.1111/j.1095-9270.1980.tb01303.x|journal=International Journal of Nautical Archaeology|volume=9|issue=3|pages=243–244|doi=10.1111/j.1095-9270.1980.tb01303.x|issn=1057-2414}} was extensively used in ancient shipbuilding to assemble hull planks and other watercraft components together. It is a locked (pegged) mortise and tenon technique that consists of cutting two mortises into the edges of two planks; a separate rectangular tenon is then inserted in the two mortises. The assembly is then locked in place by driving a dowel through one or more holes drilled through mortise side wall and tenon.{{Cite book|last1=López-Ruiz|first1=Carolina|url=https://books.google.com/books?id=bhOlDwAAQBAJ|title=The Oxford Handbook of the Phoenician and Punic Mediterranean|last2=Doak|first2=Brian R.|date=2019-07-29|publisher=Oxford University Press|isbn=978-0-19-049935-8|language=en}}{{Cite web|last=Teague|first=Matthew|date=2007-05-01|title=The Pegged Joint, Exposed|url=https://www.finewoodworking.com/2007/05/01/the-pegged-joint-exposed|url-status=live|archive-url=https://web.archive.org/web/20200925162856/https://www.finewoodworking.com/2007/05/01/the-pegged-joint-exposed|archive-date=2020-09-25|access-date=2021-04-28|website=FineWoodworking|publisher=Taunton Press|language=en-US}}

Description

Generally, the size of the mortise and tenon is related to the thickness of the timbers. It is good practice to proportion the tenon as one third the thickness of the rail, or as close to this as is practical. The haunch, the cut-away part of a sash corner joint that prevents the tenon coming loose, is one third the length of the tenon and one-sixth of the width of the tenon in its depth. The remaining two-thirds of the rail, the tenon shoulders, help to counteract lateral forces that might tweak the tenon from the mortise, contributing to its strength. These also serve to hide imperfections in the opening of the mortise.

= Types =

File:Bone Chisel reconstruction.jpg; cutting a mortise with a cannonbone chisel]]

== Mortises ==

File:Wooden hinge.JPG

File:Brick mold MET 25.3.108.jpg

A mortise is a hole cut into a timber to receive a tenon. There are several kinds of mortise:{{cite web |url=http://www.woodworkdetails.com/knowledge/joints/frame/mortise-and-tenon |title=Mortise-and-Tenon |last=Dekker |first=Michael |website=Woodwork Details |access-date=2015-02-18}}

Open mortise: a mortise that has only three sides. (See bridle joint).
Stub mortise: a shallow mortise, the depth of which depends on the size of the timber; also a mortise that does not go through the workpiece (as opposed to a "through mortise").
Through mortise: a mortise that passes entirely through a piece.
Wedged half-dovetail: a mortise in which the back is wider, or taller, than the front, or opening. The space for the wedge initially leaves room to insert the tenon. The wedge, after the tenon is engaged, prevents its withdrawal.
Through-wedged half-dovetail: a wedged half-dovetail mortise that passes entirely through the piece.

== Tenons ==

File:Table (AM 1991.193-2).jpg together.]]

A tenon is a projection on the end of a timber for insertion into a mortise. Usually, the tenon is taller than it is wide. There are several kinds of tenons:

Stub tenon: a short tenon, the depth of which depends on the size of the timber; also a tenon that is shorter than the width of the mortised piece so the tenon does not show (as opposed to a "through tenon").
Through tenon: a tenon that passes entirely through the piece of wood it is inserted into, being clearly visible on the rear side.
Loose tenon: a tenon that is a separate part of the joint, as opposed to a fixed tenon that is an integral part of one of the pieces to be joined.
Biscuit tenon: a thin oval piece of wood, shaped like a biscuit{{Cite news|url=https://manoffamily.com/how-to-make-a-biscuit-joint/|title=Our Reviews, Your Decision|work=Man Of Family|access-date=2017-07-28}}
Pegged (or pinned) tenon: the joint is strengthened by driving a peg or dowel pin (treenail) through one or more holes drilled through the mortise side wall and tenon;{{cite journal |last=Teague |first=Matthew |date=May 2007 |title=The Pegged Joint, Exposed |url=http://www.finewoodworking.com/how-to/article/the-pegged-joint-exposed.aspx |journal=Fine Woodworking |publisher=Taunton Press |url-access=subscription |access-date=2015-02-18 }} this is common in timber framing joints.
Tusk tenon: a kind of mortise and tenon joint that uses a wedge-shaped key to hold the joint together.
Teasel (or teazle) tenon: a term used for the tenon on top of a jowled or gunstock post, which is typically received by the mortise in the underside of a tie beam. A common element of the English tying joint.
Top tenon: the tenon that occurs on top of a post.
Hammer-headed tenon: a method of forming a tenon joint when the shoulders cannot be tightened with a clamp.
Half shoulder tenon: an asymmetric tenon with a shoulder on one side only. A common use is in framed, ledged, and braced doors.

Gallery

Image:Mortise.svg|A traditional through, wedged, mortise and tenon joint

Image:MortiseCornerStub.svg|A stub tenon corner joint

Image:MortiseHaunch.svg|A haunched stub tenon corner joint

Image:MortiseFoxTail.svg|A foxtail wedged tenon joint

Image:PinnedTenon.svg|A pinned corner tenon joint

Image:FeatherTenon.svg|A modern feather tenon joint (primarily called a loose tenon)

References

This article is partly based on a Quicksilver wiki article at [https://web.archive.org/web/20040329231809/http://www.metaweb.com/wiki/wiki.phtml?title=A_Glossary_of_Terms_For_Traditional_Timber_Framing_%28Timberbee%29 A Glossary of Terms For Traditional Timber Framing (Timberbee)] under the terms of the GNU Free Documentation License.

Category:Joinery

Category:Timber framing