iSpindel Lost Accuracy

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Mar 3, 2021
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Odd one this... My iSpindel seems to have lost the plot a bit...

Previous brew was perfect with iSpindel reporting accurately and reliably throughout. Next brew and the OG seemed realistic (should've compared with a manual reading in hindsight) but it soon went off the rails and the SG went from 1.060 to 1.010 in about 12 hours before continuing on to .997 before I removed it from the FV.

A quick float in water reports .998 so it's as if it's lost all the good calibration work I originally did. Anyone seen anything like this before?


Apr 19, 2021
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Paremata New Zealand
Well 0.998 is quite close to the 0000 you'd expect in distilled water at 20 celsius.

The ispindel is sensitive. As soon as you change it after calibrating I don't trust it. A minor movement during charging, the lid not going on the same will change it.
I am really careful opening it, cleaning it and plugging in and out whilst charging and putting the lid back on that nothing moves. I recheck that it floats in water at the same angle I calibrated it at and adjust that to as close as I can get it to the previous then the formula will work well.
Hot ferments such as kveik, pressure ferments and lots of krausen all affect the angle and the output I've found. Ferment before the current one my ispindel behaved odd with a suggestion of super rapid ferment and then sank.
I also check with a hydrometer the correlation at the start with the ispindel, brewspy lets you put this hydrometer or other method reading in.

You do say that it read 0.997 in the fermenter and 0.998 in water, what was the gravity reading tith a hydrometer when you took the ispindel out of the beer?

Even if the ispindel reads perfectly or I think it is I still take a final gravity reading with a hydrometer.

Check the angle in the distilled water it should be near 25 degrees if not then you might need to redo the lying flat and in water at 25 degrees and some other data points.

I have found that if the readings are crazy they stay on that crazy scale, but you can still see a trend ie no change and the timeframe.


Oct 13, 2020
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I've had mixed experience with iSpindel. It is 100% accurate when I calibrated it and have checked it since original calibration and is spot on. However in the fermentor it always reads different to a hyderomer reading. I suspect its to do with the true/yeast collecting on the lid..seems to me a very poor design to have a relatively huge rim jutting out just under the screw on cap that seems perfectly designed to capture trub/yeast. Not sure how heavy trub is, but given the sensitivity of the iSpindel it wouldn't surprise me if the few grams of the stuff collection oround the rim affects the reading. I've learned to compensate for it.. for example if target gravity is 1.012 the iSpindel might read 1.006 or something like that, so I ignore the actual figure and just look for the trend..i.e that the fermentation has finished. If I'm that bothered about understanding what the final gravity is I'll take a hydrometer reading and its always 5 points or so higher.

As cheap as the product is, I think next time I'll save up a bit longer and get a Tilt which seems to be a better and less trub catching design.


May 4, 2015
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Alloa, Scotland
I now only use my ispindel as a guide to when fermentation has finished, it lost the plot ages ago and I can't be bothered calibrating it again!