We have recently had a back-up tool made for one of our most run parts. The tool was supposed to be manufactured identically to the original (original is 3/4 years old) to ensure that they can both run on identical settings.

Since running the tool we have had issues with short shorts mainly on 1 cavity only. But recently on a different cavity. We have been removing plastic from the tips every few weeks to remove potential contamination / carbonisation (thinking this may be the issue) but last week the problem happened so often we cleaned the tips 3 times.

We have checked the cavity temps and they are all the same within 1 - 2 degrees. Our technicians and even the tool room manager are now stumped as to what the problem could be.

Can anyone help?

Its worth noting that when we have cleaned the tips they seem to be a lot smaller than the original tool (obviously the tools are not identical).

Thanks,

Jamie