Make a DIY Scace thermofilter. Parts list: Backflush insert, K type thermocouple, 1/2" piece of copper pipe, kitchen cutting board, 3 pieces of .010 steel guitar string, JB Weld epoxy. Cut a puck from the kitchen board using a door hole saw and sand to fit with a belt sander. Use a .010" nail brad and punch a hole, offset from center, in the insert and fill with the guitar string for an output water flow of 3oz/ minute. Use a nail and punch a center hole in the insert for the thermocouple. Thread thermocouple through hole and JB weld in place. JB weld the piece of copper pipe over the outlet hole to contain spray. Don't use a thermocouple with a covering (like I did) because the water under pressure pushes through it. Calibrate with boiling water.


Bottom View

That dark color is a reflection. It's chrome as you'd expect. Very strange. Guitar string plugged output on left, TC center.

Final item

I took some measurements of my Profitec Pro 500. PID at 252, ~30 grams water output in 23 seconds. 3 minutes between shots.
Shot #1: Start - 203.6°F, End - 199°F
Shot #2: Start - 202.9°F, End - 201°F
Shot #3: Start - 202.4°F, End - 200.6°F
Shot #4: Start - 202.2°F, End - 200.2°F
Shot #5: Start - 201.8°F, End - 200°F

Ideas and Insperation came from:
Building a DIY Thermofilter
http://s1cafe.com/viewtopic.php?t=1366

vecchi della seattle wrote: I took some measurements of my Profitec Pro 500. PID at 252, ~30 grams water output in 23 seconds. 3 minutes between shots.
Shot #1: Start - 203.6°F, End - 199°F
Shot #2: Start - 202.9°F, End - 201°F
Shot #3: Start - 202.4°F, End - 200.6°F
Shot #4: Start - 202.2°F, End - 200.2°F
Shot #5: Start - 201.8°F, End - 200°F

Being the owner of a "slow" Pro500, I'd be interested if those numbers held up for 60g of water in 30sec.I had done SCACE tests about 2 years ago and I think that was the water used per shot (as calibrated by that SCACE). An 18g coffee puck will generally absorb about 20-25g of water, so for a 36-40g output, you will use anywhere from about 55-60g of water. Those numbers above show very good performance for the water drawn.. but it is not indicative of making 5 actual shots of coffee at 18g doses.. just interested to see if other machines of the same model can be faster than mine.. I also use about 252-254 for my PID setting.

Great job on building the device!