Today's excursion, maintance tips

[TiTanerCZE]

On today's school excursion in a production. I dont know, but every time we have exursion I see a lot of dirty machines.

Today I have seen a reflow soldering. Some parts were so dirty from a flux that even a IPA wasnt enough, are thay some special cleaning agents or its just not possible to remove? How can something like that even happen? Is it normal?
Do not know if its just a bad practice? Can you give an info on how it should be done? 

[ataradov]

Production is always reasonably messy. There are some steps you can take to make things cleaner, but if you are dealing with chemicals, it is hard to keep things pristine. It all depends on what you have seen exactly, hard to tell how good or bad it is without pictures.

The best you can do is completely surround the machine with a case, which will contain the dirt inside. This works well for CNC machines. But this does not work well for PCB manufacturing, since it is typically organized as a series of processing steps.

There are clean rooms for IC manufacturing.They are as clean as it gets, but nobody will let a school excursion into one of those. At most you will see things though windows, and won't get a good feel for anything,