iSpindle and Fermentrack

Hi all,

Long time mailing list lurker here (repost from the old list).

My personal philosophy has always been “why build one, when you can build two for four times the cost”, with this in mind I have put together a Fermentrack build and a couple of iSpindels, which are working great.

I have spare all the parts required to build two complete iSpindels -
using the Jeffery board from Opensourcedistilling (pictured below), which is
a great project with loads of documentation. They need assembly but
everything you would need is there (minus a Raspberry pi). I could build
them for you if you wanted.

I also have PCBs and some of the parts required to put together a
Fermentrack build (see below). You would also need a display, relays,
ethernet cable, temp probes, rasp pi etc. I can provide a list of these
items if you needed.

Is anyone interested in a barter of some kind? I’d love to get my hands on
another glass carboy or keg; or perhaps you have something else that you
think might be a fair exchange?

Disclaimer: If you burn your house down or electrocute yourself using
anything you get from me then that is 100% on you.

I’m on the Plateau, let me know if you are interested by PM.


Hey Mark - I’d be interested. I replied to your email as well. Give me a shout and I’m sure we can figure out some sort of barter.



Thank you for the interest everyone. They are all gone.

Hey Mark,

There may be more people like me that are interested in building an ispindel. How has your experience using it been so far, would you recommend it, and can you recommend the most cost effective sites to buy the parts?
If it’s recommended and others are interested, I’ll coordinate a group buy of the bits & pieces.



Hi all,

The iSpindel build was surprisingly easy! I am currently brewing an oatmeal stout with it as my first run. It is fun to be able to watch the gravity drop and track the temperature fluctuations. Here is a screenshot of how things are looking.

You can see there was an anomaly in the gravity reading early on (perhaps it hit the side of the fermenter?) and it looks like my FG might end up being a little on the high side too. It’s interesting to be able to watch the kinetics of the fermentation in real-time. I use a Fermonster fermenter but be aware that the PET container of the iSpindel is pretty big and it won’t fit down the neck of a standard glass carboy.

To build mine, I simply followed the awesome instructions at .

Opensourcedistilling gives a detailed list of the required components and there are videos on how to assemble, flash and calibrate the iSpindel. The list he gives links mostly to the US Amazon site. I got pretty much all of the parts from AliExpress except for the PET container (from Ebay) and the PCBs. It took longer to receive everything but was cheaper.

Putting the iSpindel together is very easy and took me about 15 min. Calibrating it was much more time consuming but it was very accurate once everything was dialed in. I mostly followed the instructions on the following youtube video for deriving the polynomial -

I have also build a Fermentrack controller (although it isn’t quite finished and isn’t being used to control the fermentation in the screenshot above) and it makes flashing the iSpindel and accessing the data very easy. I would highly recommend it.

If anyone is building one and has any questions I’d be happy to offer my limited experience.


I’d definitely be interested in participating in or helping with a group-buy

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Awesome Sam. I’ll start looking into pricing for parts to get an idea of what it’ll cost to make one, or 5 or more. I’m on vacation starting tomorrow, so I’ll have a little more free time to throw around.
In the meantime, as people express interest I’ll add them to a list. We can eventually create a separate thread or forum to discuss the details of how all this will work without bombarding the whole list. I don’t assume everyone has a soldering iron.

And some of us are “old school” or just plain “old” and still brew in a completely manual way. :slight_smile:

Je suis interressé au group-buy !

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Don’t have to worry about that on this forum! If somebody is not interested by a thread, it can be muted.

Nothing wrong at all wit your approach Denis. When the tech fails, we all have to resort to old school methods :slight_smile:

I’d love to join in on this as well! I’ve been intrigued by the tilt hydrometers for some time.

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Glad to hear it Yacine! I’ll keep you in the loop.

@Mark, what did the cost per unit come down to for you? Some quick math using Aliexpress suppliers has me under $25 per unit (estimating 10 to build, but that may change).



Hi @kurthoughton , I think your estimate is pretty accurate. Mine came out at about $27 per unit (excluding Rasp Pi obviously).

Hey guys,

I would be interested too, if it comes already assembled, because I don’t have the equipment and experience to solder properly…

FYI, the iSpindel is also compatible with Brewfather and the BrewPiLess!


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I’d take 2 as well. Can’t have too many gadgets.

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I’d be interested Kurt. Keep me posted

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I would be interested in 3

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Hi Kurt - thanks for taking this on.

Please put me down for 2.


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Hi Kurt,

I would also be interested in 2 iSpindels!

I have some experience with electronics and can help to assemble a couple.


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