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And since they said that it uses 10-20% the water of a standard shower head...

A modern shower head uses about 2gpm, so we are talking about 0.2 to 0.4gpm. That would give us a pressure of about 7500 to 15000psi using your equation.

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That sounds like the worst case to me. They are doing their demos with 7500 psi from an outboard pump and thinking that it's going to be a minor detail that can be worked out after the kickstarter succeeds to generate a workable pressure from 15A 120v.

If they told us the pressure they're using for their demos, some smarty with a slide-rule might call them on getting that from a normal wall outlet.

This is much more realistic. 3k psi will struggle to cut a cake.

As someone used to metric, this is probably the msot confusing comment chain I've read yet o.O

You don't measure cutting force in cakes?

We measure cutting force using a very old baguette held at the Bureau international des poids et mesures.

For those that need it in metric, a cake is roughly equivalent to a scone...

At least in the UK, Her Majesties Customs and Excise tried to measure it in biscuits (which require 17.5% greater cutting force than cakes), but Mcvities prevailed in the courts.

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