ACS Evo2 Lever - new flush lever

Our forum: www.tapatalk.c...
Main review website: coffeeequipmen...
The flush lever is primarily to allow the group to be flushed clean between shots. There are some side benefits though:
A bloom phase (wetting the puck but no pressure during the pause shot). Achieved by engaging the flush lever for a few seconds and pausing (the preinfusion timer will start). Waiting some seconds, then pulling the lever down for the normal PI and shot phase.
The revision of the first flush lever to try and achieve variable pressure. It doesn't really do that (yet), however it does open the water valve earlier, giving a larger swept volume, potentially larger shots, although the group holds plenty really. With the safety system, it eliminates the need to precharge for high pressure shots, although doesn't yet allow adjustment for those low pressure shots if you want them.
Waiting for a 3rd version that might well work to give variable pressure.

[@Stan_sprinkle]

Great to see another video from you!

[@DaveCorbey]

Yes, lost my mojo for a while. Partly because I could monetise my channel but decided not to so people wouldn't see adverts. Was I surprised when google decided to put adverts on it anyway, which upset me a bit, perhaps there's less adverts than if I monetised it, who knows?

[@blackbirdmanf]

Looks great! Just out of curiosity. What makes you like higher pressure shots? And do you get a lot of channeling when you make them?

[@DaveCorbey]

I just like the extra texture, body and flavour they seem to give for all coffees and no, channelling doesn't seem to be a problem. Back in the day over 20 years ago, I tested a machine called the Isomac Giada which was an unregulated 15 or 16 bar...it cured me of any fear of higher pressures, even though 16 bar is a bit much. I don't find 11, then dropping an issue and with the Bianca, I set my maximum pressure to around 10.5 bar, to give me more flexibility and possibilities for emulating a lever shot. I don't set 11, because your getting close to the expansion valve release point.

[@michaelblackmore883]

@@DaveCorbey Interesting. With time limited machines wouldn't the higher pressure need a very fine grind, maybe finer than many grinders could manage and very tricky to set as a tiny change in setting would make a big difference at this ultra fine grind? My Elizabeth's work at about 8-9 bar so I would need a lot finer grind to run them at 10.5.

[@michaelblackmore883]

I see you have given up the deioniser. I haven't found it makes much difference since I changed grinders to the Eureka Oro SD.

[@DaveCorbey]

I busted my nice one by ripping the chain out as it was getting in the way, I have ordered another which arrived yesterday. I also wanted it to check out how the Difluid Omni particle and colour analyser might work better if it had a wash of ions to reduce static before it vibrates to distribute coffee for analysis (make the coffee less "clingy".

[@michaelblackmore883]

Couldn't you solve the problem by making the Teflon slider in a wedge shape so a smaller movement would make a bigger change?

[@DaveCorbey]

The problem is that little outcrop at the back of the lever cam moves up vertically and it's going to always go up it's full distance, so you have to be careful with the profile...That said I think you are right that the profile could be tweaked a little, as well as giving more movement. Ultimately though that slider has to move upwards by 1 to 1.5 cm more, to give a delay in opening until the lever is around 20-25 degrees past vertical. At the moment, you can only delay until a few degrees after vertical and it's not enough....we will get there.

[@michaelblackmore883]

@@DaveCorbey Probably a bit fiddly. Maybe it needs a redesign of the cam as well as the slider. I see you have changed your prototype for the production version with a neater integration of the time/pressure module at the top to match the display on the other side. I think the SS version looks better than black and is probably more durable.

[@add2093]

What grinder is that?

[@DaveCorbey]

It's called the Solo T64 and comes with SSP high uniformity SSP burrs, but it's an under the counter grinder that you have to phone Bella Barista UK and specifically ask for it (it's not on the web site)....It's a long and complicated story. Very nice 64mm flat burr grinder though. I reviewed the earlier version (now modified) here: kzbin.info/www/bejne/joKvqYCbhtqjqaMsi=7CDYJosmtEzWGOmJ