Editing Mechanical puzzle (section)

====Pyramid puzzles====
A pyramid puzzle consists of two or more component pieces which fit together to create a pyramid.<ref>{{cite web |url=https://www.canadianwoodworking.com/plans-projects/pyramid-puzzle |title=Wooden Puzzle |author=Rea Gibson |access-date=20 April 2021}}</ref><ref>{{cite book |url=https://books.google.com/books?id=RJ3aBwAAQBAJ&pg=PA114 |title=Mathematical Properties of Sequences and Other Combinatorial Structures |year=2012 |isbn=9781461503040 |publisher=[[Springer US]] |editor1=Hong-Yeop Song |editor2=Jong-Seon No |editor3=P. Vijay Kumar |editor4=Tor Helleseth |pages=114–115}}</ref> Two-piece pyramid puzzles cannot form a regular pyramid and can only form a 4 faced tetrahedron pyramid.
The solution involves facing the square faces to each other and twisting one upright to complete the four faced tetrahedronic pyramid.<ref>{{cite web |url=https://healthy.uwaterloo.ca/museum/VirtualExhibits/puzzles/pyramid/index.html |title=Pyramid Puzzles |website=Elliott Avedon |access-date=20 April 2021}}</ref> There are also four-piece pyramid puzzles.<ref>{{cite web |url=https://www.cs.brandeis.edu/~storer/JimPuzzles/ZPAGES/zzzPyramid4PiecesVer1.html |title=Four Piece Pyramid, Version 1 |author=Jim Storer |access-date=20 April 2021}}</ref><ref>{{cite book |url=https://books.google.com/books?id=ttOldWRanuEC&pg=PA13 |title=Focus on Dyslexia Research |author=Henry D. Tobias |year=2004 |page=13 |isbn=9781590339503 |publisher=[[Nova Biomedical Books]]}}</ref>