New Ispindel - when to dry hop?

[OliH]

Hi all. I started my first ferment, about 48 hours ago, using my new Ispindel to monitor the CML PIA yeast.
First of all I think I messed up the calibration! I measured the OG at 1.050 and when I dropped the Ispindel in, it measured 1.042.
Anyway that is down to 1.015 in 48 hours.
I have generally dry hopped after 5 or 7 days, thinking that was towards the end of fermentation, and bottled after 14 days. I’ve always hated opening the fermenter to take samples so just left it until fermentation has definitely finished.
Actually seeing how quickly the gravity has dropped is making think I could dry hop tomorrow and possibly bottle a lot earlier than usual as well.
What do others do?
Do you dry hop at a certain gravity or after a certain time?

 

[Agentgonzo]

First of all I think I messed up the calibration! I measured the OG at 1.050 and when I dropped the Ispindel in, it measured 1.042.

Don't worry about the calibration too much. Floating hydrometers are notoriously unreliable in their accuracy. Ignore the numbers, but use the slope of the graph to determine when fermentation is done, or almost done.

I am keeping a spreadsheet record of brews that logs (for both OG and FG) the gravity as measured by a regular hydrometer, the gravity and tilt angle as measured by the ispindel. That way, after about 4-5 brews, I have enough data points to recalibrate it.

 

[MashBag]

Very polite Gonz, full marks

 

[Danny-CIPA]

Some of these guys have been helping me with a similar issue with mine. My OG has been off by a similar amount so for now until I can be bothered to calibrate it I've offset the value of my iSpindle in Brewfather to the measured hydrometer reading. In your case you could offset it by +8 if you're confident of your reading. If it's anything like mine you'll finish similar points below where your software said you would, at least that's what I have observed.

Take all this with a pinch of salt though I'm brand new to brewing just trying to figure it all out myself.