iSpindel

[Agentgonzo]

Have to admit it's tricky as no one really explains the why it must be done this way just the how to do it.

I'm happy to explain the "why", if you tell me which bit you want to know about

 

[RoomWithABrew]

I'm happy to explain the "why", if you tell me which bit you want to know about

Thank you for the kind offer but with with the great help of the ispindle thread on the US forum and other sources I've got the Ispindels and brewpiless and brewspy all working now.
I'm now transitioning to the gravity mon software which seems much better than the ispindel firmware or is it software? and has amazing support from the developer. I like the on the fly changes that are possible with it, previously I relied on the reed switch and the ispindel being near the edge of the fermenter so I could go into the menu and change the triggering info during a ferment. Once all the activity was over a reading every few hours during the lagering phase or maturation over a few weeks was all I needed.

 

[Broomfleet Brewery]

Well what can I say, apart from a big thanks, especially to Agentgonzo and for his formula.

After 5 hours of fiddling with reset pins, wifi connections, copy and pasting the formula, and tilting it at crazy angles, it's finally communicating SG along with temperature readings.

Due to brain fade, I've not attempted calibrating it yet, as I will be quite happy for it to simply map the fermentation process for now. Pure water at 18 degrees shows 1.020 which is obviously incorrect but I'll live with it for now.

Thanks again.

 

[RoomWithABrew]

I would at least calibrate it on a flat surface to 90 degrees and try to have it near 25 degrees in pure water around 20 celsius.

If you don't you'll really struggle to calibrate.

 

[Broomfleet Brewery]

Point taken, thanks

 

[gavp1979]

I would at least calibrate it on a flat surface to 90 degrees and try to have it near 25 degrees in pure water around 20 celsius.

If you don't you'll really struggle to calibrate.

Good advice, I have never calibrated mine but it is on my list of things to do 'one day'. At the minute I just use it to keep an eye on the trend in brewfather, when SG stops going down I know it is done, would be nice to have proper readings though

 

[Agentgonzo]

After 5 hours of fiddling with reset pins, wifi connections, copy and pasting the formula, and tilting it at crazy angles, it's finally communicating SG along with temperature readings.

The first easy step for calibrating is to make sure that when it's level, it is registering as 90 degrees.
Mine was pretty close, but this is quick and easy to do.

Fiddle with the reset pins again and connect to it with your computer/phone.

Lay the iSpindel down on a horizontal surface and wait for it to stop wobbling. Then hit "iSpindel Info"

It should hopefully be registering almost exactly 90 degrees:

If it's not (if it's more than a degree-or-so out), then go into Maintainance:

and hit select Calibrate:

It will then calibrate itself. What it is doing at this point is telling the accelerometer (the sensor that tells it what angle it is sitting/floating at) that "I am currently horizontal).

Once this has finished, it should go back to the info page, and the Tilt should read almost exactly 90 degrees.

This calibration is simple and easy, and different to the "stick it in sugar water, measure the tilt and generate the formula" calibration. It basically tells the ispindel what "horizontal" is.

 

[gingerneil]

Also make sure when doing this that the lip of the tube is over the edge of the surface and not 'propping up' the tube.

 

[Agentgonzo]

Also make sure when doing this that the lip of the tube is over the edge of the surface and not 'propping up' the tube.

.
Oh. I need to adjust mine then!

(Does it actually make much difference? If the iSpindel uses a cubic equation to convert tilt into SG, does it matter if it's been calibrated with the lip?)

 

[gingerneil]

It basically means that the 90deg calibration, and therefore all measures, will be off by a couple of degrees and this will knock on to the SG output being slightly out. It may be that the calibration process can compensate for this, but I always understood that the 90deg should be done when the tube is flat to the table.

 

[RoomWithABrew]

Also make sure when doing this that the lip of the tube is over the edge of the surface and not 'propping up' the tube.

I tend to prop the rounded end of the petling so that the circuit board is horizontal that has the gyro on.
Luckily there is a nice edge of a window that I can look at and line it up parallel with.

They say that the 25 degree angle in distilled water just needs to be within a few degrees, I try to get it close to 25 but no need for it to be right on the mark.

 

[Broomfleet Brewery]

The first easy step for calibrating is to make sure that when it's level, it is registering as 90 degrees.
Mine was pretty close, but this is quick and easy to do.

Fiddle with the reset pins again and connect to it with your computer/phone.

Lay the iSpindel down on a horizontal surface and wait for it to stop wobbling. Then hit "iSpindel Info"
View attachment 76842

It should hopefully be registering almost exactly 90 degrees:
View attachment 76843

If it's not (if it's more than a degree-or-so out), then go into Maintainance:
View attachment 76844
and hit select Calibrate:
View attachment 76845

It will then calibrate itself. What it is doing at this point is telling the accelerometer (the sensor that tells it what angle it is sitting/floating at) that "I am currently horizontal).
View attachment 76847

Once this has finished, it should go back to the info page, and the Tilt should read almost exactly 90 degrees.

View attachment 76843

This calibration is simple and easy, and different to the "stick it in sugar water, measure the tilt and generate the formula" calibration. It basically tells the ispindel what "horizontal" is.

Excellent advice, and clearly explained..

 

[RoomWithABrew]

agentgonzo explained this well.

I found these videos very helpful for the setup and calibration process.

https://www.opensourcedistilling.com/ispindel-offset-calibration/
https://www.opensourcedistilling.com/the-jeffrey-2-69/
https://www.opensourcedistilling.com/ispindel-25-degree-calibration-in-pure-water/
https://www.opensourcedistilling.com/ispindel-offset-calibration/

 

[Agentgonzo]

One of the things that has annoyed me a little about the iSpindel is that if you do the original calibration, then find out that it's out by a little bit, you have to go through the calibration process again - with lots of water and sugar. It's hard to just 'nudge', your formula a little bit (unless you're happy transforming cubic equations in your spare time).

After a few brews using the iSpindel, it's close, but a little off. I measure the OG and FG with a hydrometer as well as the iSpindel, and have these values noted for different brews in my tracking spreadsheet.

Given I have the ability to do-so, I made a small tool to help you do this. You put in your original formula, and then put in the values of OG/FG as read by the iSpindel and your hydrometer. It will then scale the curve/modify the formula and give you a new formula that should work with the corrected values.

It's not as good as a full (and perfect) recalibration, but for me this is good enough (you also need to accept that the FG on the iSpindel will never be accurate, because yeast will stick to the iSpindel in a random fashion during fermentation and this will always throw your FG reading off).

Anyway, if you want to use it, here it is:
https://agentgonzo.github.io/ispindel-adjustment-tool/

It's by no means perfect and does crash a little if you put in bad values (make sure all your gravity readings are greater than 1).
If it does crash (white screen) just reload the page and start again. It's best to just paste the entire formula in rather than typing it as it'll try to update with every keystroke.

If you haven't done a proper calibration of your iSpindel, then provided you have recorded your OG/FG with both the iSpindel and a hydrometer/refractometer, then you can probably just use this (and the default formula that your iSpindel came pre-configured with) without having to do the full calibration.

If there are any problems, then let me know what you did and I'll see if I can fix it.

At the moment it always assumes a 3rd order equation (ie, up to terms with tilt*tilt*tilt in it) and only uses SG, not brix or plato. If there is enough interest in making it better, I might update it.

 

[Broomfleet Brewery]

Wizardry...thanks for sharing..

 

[RoomWithABrew]

@Agentgonzo
Very clever, would it work with a water reading and the OG? Then I could recalibrate better before the brew?
On brewspy you can enter the real measured of and it corrects the start of the graph but the end points are always the same.

 

[Agentgonzo]

@Agentgonzo
Very clever, would it work with a water reading and the OG? Then I could recalibrate better before the brew?

Absolutely, you could use water at 1.000 SG. All you need is two pairs of readings. It doesn't have to be OG/FG - I just figured that most people will take these readings anyway.

I'd suggest keeping a copy somewhere of your original formula, just in case

 

[RoomWithABrew]

Absolutely, you could use water at 1.000 SG. All you need is two pairs of readings. It doesn't have to be OG/FG - I just figured that most people will take these readings anyway.

I'd suggest keeping a copy somewhere of your original formula, just in case

I keep a copy of the formula and the angles that are generated with calibration. Provided the ispindel calibration is in the ball park it's always shown the ferment trend very well.

 

[Agentgonzo]

Could anyone help me with my iSpindel (@gingerneil ?).
The last few brews have been way out on the FG (not a real issue as the actual value from the iSpindel is unreliable anyway, and I just use it to judge when fermentation has finished).

I put it in water and it was measuring 1.020, and then I traced it down to the fact that when I have it vertical, the iSpindel is reporting that it's about 13 degrees.

The in built calibration works to set what 'horizontal' is, but how do I recalibrate it so that it says 0 degrees when vertical?

 

[gingerneil]

Where did you get it, and is it calibrated? Was it one of mine?