COVESTRO (formerly BAYER)
Bayer used to offer a wider range of on-line resources to learn how to design better Injection moulding products. Bayer has now been acquired by Covestro, and the on-line tools are very similar. Bayer also offered some documents that are useful design guidelines. Below are links to the documents and on-line tools.
Part and Mould Design Guidelines by BAYER
Bayer Part and Mold Design PDF
Material Selection Guidelines by BAYER
Plastic Snap fit Design by BAYER1
Bayer Snap Fits Design guidelines PDF
Snap Fits online design tool By Covestro
Covestro offers an online tool to calculate snaps. Is the same that Bayer used to offer:
http://www.plastics.covestro.com/en/Engineering/Tools/FEMSnap-tool
Website and results snapshots
BASF
Basf offers an online span calculator that is very useful to quickly calculate deformation and loads on spanps.
http://www2.basf.us/businesses/plasticportal/pp_techRes_tools_en.html
My Personal Excel Snap fit calculator
It is based on Basf’s Snap fit calculator and uses a simple snap design and assumptions to quickly calculate Snap Fits – It works!
Xorge Castro Snap Fits calculator
ONSHAPE – Online CAD
Onshape is a new online CAD system that may be worth trying