iSpindel - digital WiFi hydrometer

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I had the same problem. First battery was a copy and only weighed 29g was a nightmare to get the angle lower than 70 degrees. Replacement ordered and quoted at 47g, just waiting for it to arrive.
New battery arrived today - now the ispindel floats at 23.2 degrees in plain water with no extra weights - happy days!
Next step more detailed calibration - or do I take my chances and use as is ?!
 
Adean,

"Next step more detailed calibration - or do I take my chances and use as is ?!"

I'm going through the same thought process at the moment.
I think I'm going to leave it as is and see how it performs.
I'll still be using the hydrometer as the primary tool to measure OG & FG and as long as the iSpindel shows a flat line I'll be convinced that fermentation is over (as long as the numbers are in the ball park) I'll confirm with hydrometer.
 
I'm going through the same thought process at the moment.
I think I'm going to leave it as is and see how it performs.
I'll still be using the hydrometer as the primary tool to measure OG & FG and as long as the iSpindel shows a flat line I'll be convinced that frementation is over (as long as the numbers are in the ball park) I'll confirm with hydrometer.
That sounds like a plan!
I'm not going to take the readings as 100% but it's more to see when the readings level out.
:-)
 
@Adean & @ChilledGecko
Without doing the calibration you won't get a real SG or alcohol content reading. You will however be able to see that when the tilt angle is not changing, there's no longer any fermentation happening as you said.

You might be lucky and if you use one of the equations other users have shared here and it might give your SG. For example on the first iSpindle I built I used the default equation, SG was way off, but I knew when the fermentation had finished.
 
Yes, search on Ebay for seller Benpolley. I got mine from his as I've got so many jobs on to do around the house with lockdown, I couldn't face the prospect of a build, and program and setup. So just went for his prebuilt. It's been great! His instructions were also almost perfect, and it was a painless process!
Thanks pal il look him up
 
@ChrisT
Totally understand that SG values will not be true but for me the interest is to see how of the mark my iSpindel is prior to any calibration.
My iSpindel does have a calculation value already in place, so I'm assuming this has been cloned from a similar iSpindel.

Let's see, that's the fun with these things 🍺
 
The 'easy calibration' process is not that difficult and no need to waste the sugar, if equipment is sterile to begin with.

I began with tap water at 20C, then gradually added sugar checking it with an hydrometer (though I found a refractometer easier). I added the sugar in 7 stages of around 0.010 SG per stage, noting the tilt angle at each step. The 0.010 doesn't have to be exact, so long as an hydrometer reading is taken. My biggest problem was finding a small container deep enough and wide enough - all I could find was a 5L brewing bucket FV. The whole process too about an hour.

Once my calibration was done, my sugar water was transferred to my 30L and a batch of red wine started with it.

The 'easy calibration' cannot account for CO2 bubbles collecting on the iSpindel, my experiments with my present wine fermentation, seem to suggest this may not be much of a problem in wine - giving the FV a good shake up to clear the bubbles, the tilt always quickly settles to the same value. Probably more of a problem with beer brewing I would guess, but so variable it would be near impossible to calibrate for.

I was also curious about the need to fix the iSpindel in the PET and how much difference it might make to the calibration. It's a V4 pcb, fitted to a big XL PET, battery soldered and stuck to the pcb with double-sided tape. Mine is a lose, easy sliding fit in the PET. If I shake it, it can rattle, but always seems to land inside the PET in the same position, always floats battery side of the pcb lowest, with my extra weights stuck equally, either side of the battery. It always produces quite similar values when checked before and after charging, if dropped in water.

The further my first batch of wine progresses using the iSpindel, the more impressed I become with it.
 
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I used some sugru to fix the PCB as mine rattled quite a bit. However, the latest one I build needed some sanding of the board to make it fit in - so its very tight!
Where is everyone buying the Pet tubes at the moment ? I ordered some from Geoshop.LT. Geocaching - naujas Tavo hobis! but have not had a shipping update for a week!
Also, where's the best place to order PCBs these days ? How long do PCBWay take to ship ?
 
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Wow - end up being almost £5 each! I paid about £2 each from Geoshop - maybe I just need to be a little more patient!
Also turns out that v6.x of the software isn't working with the gyros I bought due to the JSON page size. Seems they are a little hit and miss. There is an issue logged on github (and I just bumped that by creating a new one). Looks like I am limited to 5.x for now. The issue is that the JSON settings cant be saved, but on 5.x its fine.
 
Cheaper from Geoshop, but I was unable to determine the shipping cost without placing an order.

My latest V6.2(?) is working fine with the gyro, producing upto 6 digits of tilt.
 
You have to go right through the checkout to the point where it gives postage. Almost doubles the cost, but still cheaper than ebay.
I have installed 6.2.0 on mine, but then get issues on the console output that the memory cant be found when reading the JSON config. Looks like something to do with the gyro chips I have used from ebay according to the git issues. I could change the code, recompile etc - but thats a pain.
Which gyros are you using ? ebay ones ? I just grabbed the best cost generic ones....
 
@ChrisT
Totally understand that SG values will not be true but for me the interest is to see how of the mark my iSpindel is prior to any calibration.
My iSpindel does have a calculation value already in place, so I'm assuming this has been cloned from a similar iSpindel.

Let's see, that's the fun with these things 🍺
Just for information these are my calibration equations. Both are OpenSourceDistilling, one has a genuine LG battery the other has suposedly Ultrafire, it's not! and it needs a really big nut to balance out. Runs for a long time though, at the moment.

With the dodgy Ultrafire battery
Degree 1:y = 0.00221726x + 0.933962026
Degree 2:y = 0.00003901x^2 + -0.0020654x + 1.041800735
Degree 3:y = 0.000001797x^3 + -0.000251734x^2 + 0.012905579x + 0.799147536


and with the genuine LG
Degree 1:y = 0.002212519x + 0.929314895
Degree 2:y = 0.00005197x^2 + -0.003551461x + 1.075605994
Degree 3:y = 0.000002283x^3 + -0.000320188x^2 + 0.015715186x + 0.762739689
 
@ChrisT, many thanks I'll compare with what I have loaded. 👍
All being well I plan to have a brew day tomorrow so it'll be interesting to see how the iSpindel maps onto the OG when I start to ferment and again with the FG at the end.
There are a lot of variables that could kick any semblance of accuracy out.
I'll report back at the end of fermentation.

Again thanks!

Kevin
 
Am I correct in assuming you're using the PCB with an XXL petling?
The normal XLs are quite snug

That is what the seller called it, a big XL. In fact it was a quite snug fit, I had to round the bottom corner and file away some from the sides of the V4 pcb. There wasn't any obvious free space to add weight at the bottom of the PET, but I managed to stick 4mm lead solder to the pcb alongside the battery with double sided tape to get the 25deg balance.

There is a small amount of movement, but it always settles in the same spot perfectly. I was curious, hearing the problems others seemed to have, of having to recalibrate everytime they opened it to recharge it. I confirmed that by rechecking the 25deg didn't vary, despite taking taking it in and out, shaking it and charging it several times - to my great relief, it only changed by a tiny fraction of a degree. It can't be much fun, having to recalibrate with each use.

I think I accidentally got it right, by having the battery soldered in, stuck firmly with double sided tape and also having the weights stuck to the pcb.
 
... I had to round the bottom corner and file away some from the sides of the V4 pcb...
The OpenSourceDistilling PCB is designed with some removable "ears" on the side and end of the PCB that are filed off to give a snug fit into YOUR pelting. Also there are no tracks near the edge of the the PCB that can be damaged by over zealous filing!

I just wish I could find a smaller FV that the Pelting will fit into!
 
I just wish I could find a smaller FV that the Pelting will fit into!

As already suggested above, any size of iSpindel will certainly fit in a one gallon/ five litre FV of the plastic bucket with lid type and they are much easier to clean than the traditional demi-john. I cannot see anyone wanting to make less than that amount.

They come with an un-drilled lid, so one needs to be made for the airlock.
 

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