If you own a pump espresso machine, then backflushing is a maintainance step that you would have to do on a very regular basis. Sadly, this essential maintainance step is something a lot people forget to do and then they would wonder why their espresso taste like crap for no apparent reason. Additionally, prolonged period of not backflushing will eventually end up in clogged pipes and subsequent malfunctioning of the espresso machine. This is something that I personally see a lot because I have been working on many abused commerical espresso machines and I essentially see the same thing.
With a very few exceptions of espresso machines that do not required to be backflushed such as those that do not have three-ways solenoids to relieve pressure or lever espresso machines, most machines for the home enthusiasts and for profesional usage require periodical backflush with coffee detergent and more frequent blank backflush with just plain water. If you are like me and tend to misplace things, they you probably end up losing the blind backflush basket that come with your espresso machine at some point. For me, what happened was I lost the blind portafilter basket for the Nuova Simonelli Musica when I was moving from my old apartment to my new current place. At this point, I have two options, buy a new blind basket from a supply vendor such as this one:
or this one:
These two item are availabe from espressoparts.com and they actually have a free shipping option which is excellent. However, I was in urgent need for a the backflush basket and could not wait for it to arrive and got an idea from the blind plastic insert above so I decided to make my own blind portafilter basket. I decided to sacrifice the Musica's single shot basket that I still have and really never use because I find that I could never been able to make excellent espresso with it. Then I cut out a circle shape from a clear plastic cover (it could be from a yougurt container lid) or anything you have laying around. It does not have to fit the bottom of the basket perfectly. Then I use foodsafe silicione caulk that I have lying around that I use for my shower to stick the circle plastic cutout to the basket. I let it dry for several hours and voila, I have a perfectly functioning backfush basket.
Granted, I could have bought the basket insert or the blind metal basket from espressopart.com for relatively cheaply especially with the free shipping coupon that they have, what I came up with worked equally well and I do not have to wait for the item to come as I already have these things laying around!