Two (2) litres of "forbidden lemonade" (Prestone #Screenwash, distributed by #Holts of #England ) at around 30-50% dilution, tests at around -7 degrees Celsius on the #refractometer - should be enough not to freeze in the jets during the next few days of cold #weather
#homebrewing gear question: The readings of my digital #refractometer change over the first 10-20 seconds for the same sample, when taking multiple measurements.
For example…
t = 0s: 12.0 %Brix
t = 2s: 12.5 %Brix
t = 5s: 12.8 %Brix
…
t= 20s: 13.9 %Brix
Eventually it stabilizes at a number that’s about 1.5-2 Brix higher than the initial measurement.
Is this normal or do I have a defective device? Is the first or the last reading correct?
I double checked the #screenwash scales of the #refractometer with spiritus (denatured ethanol), diluted from approx 92% (according to Tesco) to 60%, which should have a freezing point of -37,5 degrees Celsius
I did also try diluted IPA but readings were way off, it seems like *both* the scales on this one are for ethanol mixtures and you are supposed to take an average reading (this isn't mentioned anywhere in the instructions for this or similar models, even the pricier ones!)
Newest piece of gear: A 1960's East German #refractometer. The wrench for the calibration screw is missing (1.3 mm square key) and the union nut for the thermometer is a bit loose (M16 x 0.75 ?).
Unfortunately Google turns up nothing in regards to spare parts, or even parts that could be simply converted without special tools I don't have.
Using a pair of tweezers for calibration and lots of teflon tape on the thread works, though :)