Are Mechanical Connections Reliable?
I have read many forums on the debate between crimping and soldering contacts. Personally, I prefer crimping contacts because the process is faster and more repeatable if performed properly.I have outlined some key characteristics to look for when inspecting your crimp to make sure you get a reliable, sustainable connection.
The Proper Tool for the Job
Having the proper tool is the first step to ensure your crimp will be of high quality and repeatable. Tooling comes at a cost and most tools are contact specific but I assure you, it will be money well spent if you decide to invest it. Tooling can range from hand crimpers to fully automated work stations depending on your requirements. Contact manufacturers will have full information on tooling related to their contacts and offer you various options to meet your needs.
Crimp Height
Crimp height is a key indicator of your quality and is easily measurable. We use a blade micrometer to measure and verify the crimp height for all tooling. Contact tooling comes with manuals which have technical data pertaining to the crimp height value. This data is also available from the manufacturers’ websites.
Pull off Force
Measuring the force required to pull the contact off of the wire is another key characteristic of your crimp quality. This is a destructive test in which the contact is clamped and the wire is pulled until the crimp fails. The value at which the crimp fails is directly related to the cross section of the wire. The larger the cross section, the larger the force required to pull off the contact. Charts are available from many online sources as to the pass values of a pull test.
Visual Inspection
When first using a hand tool or applicator, visually inspect your crimp to verify the quality. Tyco has a crimp quality poster that conveniently lays out visual characteristics highlighting both correct and incorrect practices.
http://tooling.tycoelectronics.com/pdf/US_crimpposter.pdf