# How do spring levers allow variation is pressure for profiling?



## SafetyThird (Aug 16, 2020)

I'm a new la Pavoni owner and just starting to get to grips with it. I understand how, being fully manual, you can change the pressure and time to allow you to change the size/extraction of a shot. I'm wondering how this is achieved with a sprung lever machine, from videos I've seen, you pull the lever down to prime the pressure and then when it's released, you just get what that spring gives you. Can you change anything in the shot and, if so, how?


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## The Systemic Kid (Nov 23, 2012)

With a sprung lever machine - you can't play around with the shot pressure - machine takes care of itself. You can't really increase the amount of espresso produced. Londinium, for example, has a volume capacity of about 60 ml. It's possible to do Fellini pulls with a sprung lever and manual lever to increase the amount of water used in a shot as in this example but I've never bothered.


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## jules1 (Mar 28, 2020)

You can keep hold of the lever and resist the spring pull to whatever degree you want and at any stage of it's journey. This reduces the pressure. You can't increase pressure beyond the spring strength. You could stop it completely midway through the shot if you want!


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## jules1 (Mar 28, 2020)

(or more accurately, resist the spring push...)


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