Since there was a poll in the General Modeling forum on this practice I thought I would post what I was told about backflushing here.
As I said in another post, I was told not to do it by Dave at Coast Airbrush and my friend Scooter agreed with Dave and didn’t recommend it either.
I also asked Ken Schlotfeldt at Badger and he thinks backflushing is a good thing to do.
Here is his response and it makes good sense:
"If the airbrush is manufactured properly backflushing does not cause material to get into the mechanical parts.
To realize the benefit of backflushing try this – spray pure cleaner through your just used airbrush until it appears clear/clean, making sure the cleaner is still pure then backflush it and see if any color comes back into the pure cleaner. If there is color, then backflushing has indeed cleaned more material out of the airbrush – usually there is. Without backflushing that material would remain in and set up in the airbrush. Initially this small amount of residual matter would not affect the performance of the airbrush, but over time the residual build up could eventually have an adverse effect on how well your airbrush sprays, and lead to the need to take the airbrush apart to thoroughly clean each and every part of the airbrush that comes in contact with paint. In my clinics I preach to not disassemble your airbrush unless you are going to put it in storage. Take the time to spray cleaner through and backflush your airbrush, and you’ll never have need or reason to take it apart. For a high percentage of airbrush users, especially novices this is where problems can start due to confusion and incorrect re-assembly.
I backflush an airbrush anytime I am going to leave it sit for an extended time without use. Backflushing can loosen up residual material that, if simply spraying cleaner, may remain in the airbrush because it is “attached” to the needle or paint chamber. Back flushing can also minimize the need to disassemble your airbrush for more thorough cleaning, because it often times loosens the residual material that you would otherwise need to take the airbrush apart to get at.
The key to fully benefiting from and properly backflushing your airbrush is to spray pure cleaner through the airbrush again after you have backflushed."
So there you have it. Take all the information that you have learned and decide for yourself if you think this practice is how you want to clean your airbrush. [;)]
Mike