ACS - At World Of Coffee - Copenhagen

Cuprajake

I purchased the Leva because I wanted a lever machine - had my eye on the first Vesuvius lever then on the Vostok finally this one !

I didn’t want a pump driven extraction and the ACS was the best out there – in addition I have liked what Corby has been involved with

As for the gear pump quicker ramp up probably but low ml/sec .

I do not know if you are aware but a smaller diameter basket ( 54 vs 58 ) will produce a lower total weight on the puck - in fact water pressure is a false indicator of what the puck is subject to. Dalla Corte with their 54mm makes this clear on their website - a 5 bar pre infusion on 54 is a lower total weight than it would be on a 58. This also was discussed with Paolo - as a consequence he managed to find springs for my machine that would give the 54 mm puck the same total weight as the 58mm would yield .

selmerfudd but where you got the idea that I expect the safety system to work with no water i will never know

well, lets try here…..

selmerfudd 1- How come the safety system only works when the machine is turned on I thought it was a passive system not active?

with the machine turned off it cant actually pump water it to the chamber unless im missing something basic here!

As you are unique with your pre infusion requirements and the rest of the world is doing it wrong, then, as Dave suggested turn off the auto dump and set what ever pre-infusion you require. then end the shot at you unbelievably low setting. what volume are you looking for 60ml or something?

your requirements are so far away from Normal its difficult to see what you are trying to achieve or prove.

selmerfudd to my knowing the safety system has not been described as to how it functions, as you know it has been kept quite hush hush by ACS- as well as by Dave Corby

its so simple there’s nothing hush hush about it. As an engineer im sure you can work out the flow and pressure differences produced by an open cylinder system as opposed to one single 1mm diameter hole. nothing more to it. lever rises (piston lowers) slowly due to pressure build up within the virtually closed cylinder. Basic engineering!

I asked where you are as the links I gave were more relevant to the UK and Europe than the US or cloud cuckoo land.

selmerfudd -whether it functions on a hydraulic or a purely mechanical system is anyones guess

no guessing required its all well documented, but to check and analyse it requires the removal of 1 x No2 Ph head set screw and 4 x nuts with a 10mm AF spanner / wrench / socket. Simple enough for all of us, let alone an engineer.

As for the Basket size even Lance agrees its a better size on this group than the 58mm, even if that’s a slight misquote!

Anyway its good to see you are happy with your purchase. Its difficult to realise we have the same machine.

Best coffee I’ve had from my many machines. more to the point its more precise and consistent. (Still waiting for J to sell the Decent though, if Graham doesn’t get there first) 😎

selmerfudd My questions

1- How come the safety system only works when the machine is turned on I thought it was a passive system not active?

This may be of use to you .

https://coffeetime.freeflarum.com/d/10/4757

Adrianmsmith

Yes the mod is indeed interesting-Thank you– I am new to the Coffeetime forum, so many of the discussions i have not yet perused .

I also was concerned about the lower pressure attained with the safety system - as well as the overall weight discrepancy on the puck between 9 bar at 54mm and 9 bar at 58mm , well I managed to obtain 11.7 bar with safety ,close enough !

I still want to experiment with the flush lever pre charge and pre infusion , but so far I have not spent much time studying how to best use the flush system - to see what benefits it could yield.

thanks again interesting reading for sure

selmerfudd

First off im not suggesting anyone does the mod, it was more to show you how it works…..

As for pre charge the best way is to set the flush lever so the pump engages as soon as you move the lever.

Make sure you move the lever to the pump on point . Pause until the pump starts

Get used to the speed required to move the lever so the pump stays on and you do not hit pre infusion pressure until the lever is at the bottom.

Why……..

By doing the above you will have very little air in the cylinder, only water.

So what……

This will give maximum pressure as air is easier to compress .

Im not buying in to the need to go past 11 bars . Some people mod to lighter springs to achieve lower start pressures as they want 9 or 10 bars max.

Psi is psi , or bar, at 20mm or 58mm.

Kg dead weight will give lower psi at 58mm and 54mm