Depends on the requirements of the project, but we have had good luck with acrylics. We typically will add Heli-Coils to the threads to beef them up. Have also done lots of work with HDPE, LDPE and PP, but they are more prone to warp and stress relieving.
Hi Terry, Other than Jeff's suggestions... For bearing type parts Acetal materials are often machined and can give a nice finish. Definitely do not want to overheat and give off gas while machining though as this can get to be explosive. Another bearing material that is commonly machined is UHMWPE. This is for slipper bearing such as used in conveyor systems and has mostly replaced solid Teflon for this purpose. Also for cheaper parts (again depending on function) PVC can be pretty easily machined and is normally available in solid sizes that allow this. You can also readily solvent glue PVC blocks together to form larger blocks. I have also seen ABS machined but typically this is only available in sheet form up to around 3.2mm (0.125") thick.Regards, Brent Drysdale Regards, Brent Drysdale Mechanical Designer Tait Electronics Ltd (www.taitworld.com) New Zealand Ph. +64 3 358 1093 Terry Thomas wrote:What are you using for machinable plastic? I do a lot of drilling so the material can not melt during this process. I like to use polycarb but the money people are crying about cost?