iSpindel - digital WiFi hydrometer

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Does anyone use the iSpindle for automation or are most people just looking at the output? I spent yesterday hacking about and set up this simple python server and I'm planning on using the temperature readings to turn on/off some RF controlled plug sockets to control my fridge temp. I looked at BrewPi and CraftBeerPi but I wanted something simple to hack and they seem very geared towards direct hardware control.

Yes... I have mine reporting out ubidots, and have set high/low temp alarms. When they are hit, I get ubidots to send a webhook message out. I used to aim those at IFTTT to then talk to a smart life plug. However, smart life recently dropped support for IFTTT, so I have now installed Home Assistant on my server and send the webhooks to that instead and on to the plug. Means I can control the temp of a brew to within about 2C - and probably tighter if I upped the reporting intervals. I dont do anything for the SG - normally just keeping an eye manually to see when it tails off.
 
Yes... I have mine reporting out ubidots, and have set high/low temp alarms. When they are hit, I get ubidots to send a webhook message out. I used to aim those at IFTTT to then talk to a smart life plug. However, smart life recently dropped support for IFTTT, so I have now installed Home Assistant on my server and send the webhooks to that instead and on to the plug. Means I can control the temp of a brew to within about 2C - and probably tighter if I upped the reporting intervals. I dont do anything for the SG - normally just keeping an eye manually to see when it tails off.
Nice, thanks. There are a lot of ways to skin this cat :)

If I get around to it I'd like to set it up so I can specify a recipe and have it import fermentation temperature for the recipe from Brewers Friend, but knowing me I'll porobably lose interest before I get that far.
 
My ispindel behaves somewhat strangely - works fine when sitting on the side, updates at whatever interval I set it, but as soon as it's dropped into a fermenting bucket right next to that position, it stops updating. Take it out & do a reset, it starts up and updates again. Back in the brew, same behaviour. It then updates at an entirely arbitrary interval ranging from once an hour to once every six hours or so. The wifi signal is good, the battery is over 4V, and I can't make much sense of what's going on.

SS FV?

Mine was intermittently missing readings but a WiFi extender plugged in very close by completely resolved it
 
SS FV?

Mine was intermittently missing readings but a WiFi extender plugged in very close by completely resolved it
Thanks Gerald, I moved the (plastic) FV indoors virtually on top of the wifi box, and the ispindel has started updating every 5 minutes. Odd, because I have good wifi signal in the brew shed, and other small monitoring devices in there connected to the wifi directly. It's a strange one.
 
This thread has me wondering where the antenna is. I put the iSpindel in the 'test tube' with the on-off switch at the top. But if the antenna is at the other end it might be shielded by the water. I'll check the signal both ways when it's in configuration mode and hosting its own wifi.
 
Mines arrived today. Cheers Neil. 👍

I have no idea how to set these Up so it’s gonna be a weekend of studying this site!

One quick question. Does anyone use this with a stainless fermenter in a brew fridge. Sounds like a WiFi booster is needed but I’d be keen to here from anyone using it with a as brewbucket or similar!
 
There would seem to be a market for these and having a sterilised one floating about telling me the SG at any time I would like to read it would frankly be brilliant.

I am now on my third brew, using the iSpindle and it is absolutely great, it being so easy to monitor it at a distance. I have always struggled to read with any accuracy an hydrometer and the iSpindel produces such great accuracy.

I would point out a couple of things to be aware of...

The XL PET is slightly narrower at the neck, than further into the body, which means if you trim the pcb to just fit through the neck, it will be loose down in the body - no way around that. I used the V4 PCB, but decided the best way for the calibration to remain stable is to fix weights to get 25deg calibration, is to fix them to the pcb itself and on the same side as the battery. No need for a battery holder [1], stick both the battery and the weights directly to the pcb and all as close to the lower edge of the pcb as is possible. A bit of trial and error is then needed to get the 25deg AND ALSO with the pcb floating horizontally across the narrow width of the pcb. Sticking weights to the inside base of the PET is entirely the wrong thing to do - any change in relationship between PET and pcb, then causes calibration errors.

The lower down the weight in the PET and the more compact the main weights (battery and calibration weights), the more stable the calibration will be. I used that strong sponge double sided tape, to stick both the battery and the weights in place, alongside the battery. For the weights I used 5mm plumbers lead solder.

My pcb is able to move slightly inside the PET, shake it and it will rattle a little, but despite this its calibration allways remains spot on. The thing is, it always drops back down into exactly the same position inside the PET, once in the FV.

[1] The 18650 will likely survive 500 to 800 recharges before it needs to be replaced, the charger is built into the iSpindle. How many of us are likely to hit 500 to 800 homebrewing sessions and even need to replace the battery? One battery charge may even survive two, three or more batches. The battery in an holder will be higher up the pcb than just the battery without the holder, the battery is by far the heaviest component and needs to be as low as possible down the pcb for best stability. I the battery ever does need to be changed, then the iSpindel will need to be recalibrated anyway, whether in a holder or wired direct to the pcb.

In the UK, Torchy is one source of absolutely genuine 18650 cells.
 
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This thread has me wondering where the antenna is. I put the iSpindel in the 'test tube' with the on-off switch at the top. But if the antenna is at the other end it might be shielded by the water. I'll check the signal both ways when it's in configuration mode and hosting its own wifi.

On my WEMOS, it is at the top, by the charging socket. Look a wiggly track on the pcb, like castellations - that is the antenna. The water is the least of the problems for reception. For the size of the unit, it puts out a very strong signal.
 
On my WEMOS, it is at the top, by the charging socket. Look a wiggly track on the pcb, like castellations - that is the antenna. The water is the least of the problems for reception. For the size of the unit, it puts out a very strong signal.
It does not receive well compared to a Tilt. If you turn it round it assumes the same attitude but the cap is underwater! It made a 5dB difference outdoors, at thirty feet.
 
Mines arrived today. Cheers Neil. 👍

I have no idea how to set these Up so it’s gonna be a weekend of studying this site!

One quick question. Does anyone use this with a stainless fermenter in a brew fridge. Sounds like a WiFi booster is needed but I’d be keen to here from anyone using it with a as brewbucket or similar!

There are two suggested solutions...

1. Electrically insulate the lid of the FV, from the body of the FV.
2. A passive antenna system - small receiving antenna inside the FV, short bit of coax leading out of the FV, sealed where it exits, then the top end of the coax stripped back a little way to bare the inner to make suitable second antenna.
 
It does not receive well compared to a Tilt. If you turn it round it assumes the same attitude but the cap is underwater! It made a 5dB difference outdoors, at thirty feet.

I have a batch on now and reporting every 15 minutes, absolutely regularly - as it has done with earlier batches. Distance between the router and the iSpindel is about 15 feet, with the thickness of two brick walls between them, in a plastic FV. The reported signal strength varies between -57 and -73dB. How it lies in the FV does seem to make a difference, but the biggest variation seems to be due to outside factors.

The cap of my XL is just below water at the lower edge of the cap/ most of the cap is above the level.
 
My ubidots i saying I have almost reached my daily limit of 50k dots. wtf is this? I have set it to receive SG, temp and voltage every 15 mins, surely that can't hit 50k dots a day?

edit: it keeps on updating the number of dots but hasn't updated the dashboard since 7pm.

It's sent 4k dots in ten minutes, now locked out of it
 
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I don't use ubidots but it looks like ingestion is limited to 5000 dots/day. Still, that should be enough to report all 4 metrics every 2 minutes... Perhaps there's a monthly cap too?
 
It's 50k a day for extraction

I think what happens is every time you access the dashboard, it is pulling in every single data point, from every single widget, every time. I had the dashboard open all day and was pissing about with a load of widgets to get the look I wanted so not only every 15 minutes it was accessing hundreds of data points but every time I reloaded the dashboard to see what it looked like it accessed all the data too. seems a silly way to do things but what do I know

But I still don't understand how it used 4k dots in one reload though if that is the case
 
I've recently received my iSpindel from @gingerneil (thanks for sorting out Royal Mail athumb..). I've been poking around some of the server options for logging the data and have found them either a bit lacking/limited/frustrating so I've decided to build my own using a Firebase backend. If anyone is interested I'd happily share the build when it's in a fit state, as all feedback is useful! The plan is to make it super easy to deploy on a free firebase instance, then have easy access from anywhere.

Here's a couple of screenshots to give you an idea of where I'm going:



 
Yeah same. Its working fine now,

I soon ran into that problem, whilst assessing my newly built iSpindel a few weeks ago. Never set Ubidots to 'Enable Realtime' ( right pointing arrow upper right), that rapidly reloads and updates your Ubidots webpage and will very rapidly use up your Ubidots data allowance. Instead, only use the manual page refresh of your browser (usually top left).
 
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