While browsing the Internet Archive the other day I came across this gem. "Springer Handbook Of Mechanical Engineering" was published in 2008. It was uploaded to the Archive's "Open Source" file and copyright status is not stated. If you choose to download, there are a number of file formats available, the pdf file is 62 MB. If you can still find this in the retail market, there is an accompanying DVD.
At almost 1600 pages this is a huge handbook, it is a very complete documentation of the state of the art as of 2008 (computerization nowadays, can bring big changes in 9 years).
Rather than get long winded here, the contents pages will do a much better job of promoting this excellent text than I can.
Click on the pages to expand. If you would like to download this text, this is the link to the Internet Archives download page. https://archive.org/details/SpringerHandbookOfMechanicalEngineering.