Where do you buy those orings and what lube type do you use?

I bought a bag of 100 for about $10 on line.
Any bearing shop should be able to sort you out.

Molykote 111 is the go to grease for groups, it is expensive but a tube will last you a lifetime.

Just a quick update, 1st Line is shipping new part. They do stock this part: Lelit 2200095L1 E61 Group Cap LPC. Just on Thursday this part on 1st-Line Equipment website was $9.99. I just looked now is $69.95, What could have caused that change? Wow!

I was wondering if you could use AFLAS o-rings? This material comes in that specific size. They are used in the aerospace industry, developed by NASA. I've successfully used them to replace all the silicone o-ring on my BDB, about 15 in total. None have leaked so far, the oldest has been in use for over five years.

Just a quick Google, so no proof.
It would appear that the Viton might work better in the FCD as a moving application.

Is aflas the same as Viton?

Aflas® can withstand higher temperatures and Viton® performs better at low temperatures. A point often overlooked is the test data doesn't always reflect the compound performance. In reality, Aflas® exhibits a poor compression set at high temperatures, making it better suited for static applications.5 July 2018

I would suggest taking the needle valve apart every year or so. It should be lubed and possibly have the O rings replaced if they are badly worn. Mechanically the Profitec and Lelit are identical aside for the paddle itself:

Profitec Pro 600 - No Pressure/Water from Group

Any machine experts in the San Jose/Gilroy area? I'd like to have someone come over to do in house training, alternatively if there is a meet up spot we can do that too. I'm willing to pay.

Grind finer, adjust flow control, change tamper pressure, all things I've tried to master in the last 2 years of owning this equipment - frustrated as I'm trying to get better.

Amberale wrote:Just a quick Google, so no proof.
It would appear that the Viton might work better in the FCD as a moving application.

Is aflas the same as Viton?

Aflas® can withstand higher temperatures and Viton® performs better at low temperatures. A point often overlooked is the test data doesn't always reflect the compound performance. In reality, Aflas® exhibits a poor compression set at high temperatures, making it better suited for static applications.5 July 2018

That's a good find, not sure why I didn't remember that. It also explains why my Aflas o-rings have performed so well in their static environment. So my question is, does the o-ring inside the Bianca worm gear actually go through compression and decompression as the paddle rotates?

Probably nowhere near enough to be a problem especially considering the relatively low cycle count and speed of rotation.
At a few cents each when bought in bulk (100 pieces) changing them out and lubing every 3 months is a no brainer.