Have you checked the group pressure lately? redux

[Tex]

Two videos of the same thing - testing a Gaggia Classic group pressure;
 
 1) is using a dry pressure gauge
 

2012-01-19: Gaggia Classic, testing group pressure

 2) is using a liquid-filled pressure gauge
 

2012-01-19: Gaggia Classic, testing group pressure

 
 As you can see, there's a ramping of pressure - common with a vibe pump. Pretty
 consistent at 10 bar static pressure.

[Ascholten]

If one can not get a liquid filled gauge, a shutoff valve, needle type valve works best and a regular gauge, close it down until the needle is not jumping around but still reading and it will work fine.  We do this to dampen the gauges on our Hpacs at work.

I havent checked mine and given they dropped the one I probably should check it just to be sure but it seems to be working fine.   

Do espresso machines have a habit of straying after a while or is just a general good to do just to check thing?

Aaron

[Tex]

If one can not get a liquid filled gauge, a shutoff valve, needle type valve works best and a regular gauge, close it down until the needle is not jumping around but still reading and it will work fine.  We do this to dampen the gauges on our Hpacs at work.

I havent checked mine and given they dropped the one I probably should check it just to be sure but it seems to be working fine.   
Do espresso machines have a habit of straying after a while or is just a general good to do just to check thing?

Aaron

The one in the video was last adjusted 2+ years ago, and is still where I set it then. Keep them clean and they pretty much take care of themselves. Ignore the PM and they'll be junk<sigh>.

[Ascholten]

so how often should I backflush and what all is involved in that?  I have a blank for the portafilter already.

Aaron