Some Motors Incompatible with Statorade / Ferrofluid cooling?

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Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by john61ct » Mar 24 2020 8:43am

Reference thread, specifically about QS motors viewtopic.php?p=1539180#p1539180

I had thought that only mechanical design issues determined whether or not FF could be used in a given motor?

But apparently it is (of course) more complex than that.

Thought a generalized thread would be useful for discussing the various factors

and collecting a list of motors that will

A. definitely be OK

B. definitely are not compatible, and

C. the in-between cases

Let's try to keep to the ferrofluid aspect, or at least just tolerating & shedding heat,

rather than discussing other aspects of motor's performance.

Any other reports of FF loosening the magnets on QS motors, or otherwise dissolving the glue holding them in place?

Other manufacturers' motors?

Is the problem easily fixed by the user?

Are there safer types of FF formulations?

Sample format for further reports:

MOTOR MAKE/MODEL:
FF BRAND:
TIME TO FAILURE:
REGULAR TEMPERATURE REACHED:
OTHER RELEVANT INFO:
Last edited by john61ct on Mar 24 2020 8:43am, edited 2 times in total.

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Re: QS Motors incompatible with Statorade / Ferrofluid cooling?

Post by madin88 » Mar 24 2020 9:25am

Hope it is ok to post about issues with motors from other manufacturers too?
In my case this happend with one MXUS V2 where about 10ml of genuine Statorade "Type B" was used.
It did react like a solvent with the glue and dissolved it. All the magnets came loose, and the glue, which normally is rather brittle and hard, had a consistency which was something between oil and gum with brown color. Kinda weird. btw: all of the FF was gone

The time between fill and failure was about 2 years and 4000km.
A temperature limit was set to 110°C (maybe 120°C max).
Motor was sealed up (no water or rust inside).
john61ct wrote:
Mar 24 2020 8:43am
Is the problem easily fixed by the user?
Depends on if the magnets did suffer damage from spinning freely inside or not. In my case some were broken and so i decided to replace them all with magnets from V3 motor (the stronger ones with curved shape) which i had lying around from planned projects with those motors.
As glue i used "UHU liquid metal" which is some sort of high temp epoxy used for steel and metal parts. It has about one hour work time which is important since you need enough time to put them in and align them in one working step.

I remember that i made pics. Will take a look and attach them here.

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Re: QS Motors incompatible with Statorade / Ferrofluid cooling?

Post by john61ct » Mar 24 2020 4:41pm

Yes, including other motors is fine, and that is a superb contribution right there so far.

I wonder if motor manufacturers have become aware of this issue and started using more FF-compatible adhesives in recent years?

Or if there are different FF formulations that are safer to use with a wider range of motors?

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Re: QS Motors incompatible with Statorade / Ferrofluid cooling?

Post by DogDipstick » Mar 24 2020 4:51pm

1 question: Does anybody ( expert) know EXACTLY what type of adhesive the motor is constructed with?
83.1v of Ironhorse XC.. :) :bolt: by Chevy :bolt: :D Broke 10 horsies :twisted: (..about 80% healed..).. :? Anybody.. what equals √3 times the line to neutral voltage? Asking for a friend.. :| (gottenymoem4115thangs?Yall?) :confused: Fabricator @ BSECo. Inc.

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Re: QS Motors incompatible with Statorade / Ferrofluid cooling?

Post by john61ct » Mar 24 2020 5:26pm

Ha, you think most of the manufacturers even have that info?

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Re: QS Motors incompatible with Statorade / Ferrofluid cooling?

Post by DogDipstick » Mar 24 2020 6:51pm

john61ct wrote:
Mar 24 2020 5:26pm
Ha, you think most of the manufacturers even have that info?
Can I XRF it? I bet I could. I will when I have my motor open. Someday.
83.1v of Ironhorse XC.. :) :bolt: by Chevy :bolt: :D Broke 10 horsies :twisted: (..about 80% healed..).. :? Anybody.. what equals √3 times the line to neutral voltage? Asking for a friend.. :| (gottenymoem4115thangs?Yall?) :confused: Fabricator @ BSECo. Inc.

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Re: QS Motors incompatible with Statorade / Ferrofluid cooling?

Post by serious_sam » Mar 26 2020 5:19am

john61ct wrote:
Mar 24 2020 8:43am
Let's try to keep to the ferrofluid aspect, or at least just tolerating & shedding heat,
Excellent topic. Good information for prospective FF users.

If I could make 2 suggestions.
1. Remove the "QS" from the title. Make it about FF in any hub motor.
2. If people could post their bad experiences with FF in a standardised format, it'll be easier for people to absorb at a later date. For example:

MOTOR MAKE/MODEL:
FF BRAND:
TIME TO FAILURE:
REGULAR TEMPERATURE REACHED:
OTHER RELEVANT INFO:

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by john61ct » Mar 26 2020 9:00am

done thanks

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by 999zip999 » Mar 26 2020 10:33am

Magnets a very brittle and must be handled will extreme care and they can jump and brake. I used JB weld as is good to 600 degrees. They many different glue temp with different JB weld glue. Motor markers will any glue they can. Just like Chinese battery packs. Aka edge 1,500 motor.

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by DogDipstick » Mar 26 2020 10:58am

john61ct wrote:
Mar 26 2020 9:00am
done thanks
There is more than one brand of feroflud? I read two places get it to the averave ebiker.. Luna and Grin... tht the stuff is the same stuff ( chemical comp) as te other..

You guys. Been here for years and start the thread with a QS but then change that. I know you have been looking into this stuff for 10 years +... Sam and John.... You got the experience.

Started with some standardization.. now we just listing experiences, nothing concrete. I really want to know why my motor has lasted dry for over 700 miles now no damage found for well over 150c running... Temp hard limit is 180c on my bike.

Very interesting that a product meant for "high power builds" doesn't work and cooks off and melts magnets.. on high power builds... I do think I have seen evidence of the QS line taking a good beating hotter than the norm.

You guys know, what about the MCR Toner and Peanut oil? Or the ATF? Both are something I would likely try before ferrofluid, if ferrofluid cannot even handle a mxus3K. I am about to douse my hub t0 the axle in ATF. lets see what the before/after data logs say then. :) Takes alot of temp to coke ATF from what I know.

ZOk I'll shut up with nothing to contrib... and just lurk the rest of the thread. I am sans experience.
83.1v of Ironhorse XC.. :) :bolt: by Chevy :bolt: :D Broke 10 horsies :twisted: (..about 80% healed..).. :? Anybody.. what equals √3 times the line to neutral voltage? Asking for a friend.. :| (gottenymoem4115thangs?Yall?) :confused: Fabricator @ BSECo. Inc.

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by john61ct » Mar 26 2020 11:53am

My understanding is that some adhesives used by some manufacturers get **dissolved** by the FF.

If I am wrong please correct me.

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by serious_sam » Mar 26 2020 5:36pm

john61ct wrote:
Mar 26 2020 11:53am
My understanding is that some adhesives used by some manufacturers get **dissolved** by the FF.
That sounds like what's happening. The adhesives need to be oil resistant in order to run FF. It's highly likely that not all motor manufacturers take that into account. Possibly temperature plays a part too. Lower temp adhesives are going to be weakened and more susceptible to solvents (oil) at higher temperatures.
999zip999 wrote:
Mar 26 2020 10:33am
Motor markers will any glue they can.
Agreed. The tricky thing for us to keep track of what motors are "FF proof" or not, will be that the individual manufacturers most likely don't consistently use the same adhesives. Some probably just source what's cheapest/available at the time. Even if the motor manufacturer does the right thing, their suppliers could substitute products without telling them. Happens all the, time in my experience. And surface prep for adhesives is almost (sometimes more) important than the adhesive used. As everyone knows, QC is the biggest problem with Chinese manufacturing. You never know what you're going to get. Sometimes you get lucky. Other times not. So even if one *insert motor name here* fails from FF, others of exactly the same type may not.
DogDipstick wrote:
Mar 26 2020 10:58am
There is more than one brand of feroflud?
There are many types of FF. Some even home made. Statorade is a single type of FF sold by Grin. I bought mine from sketchism via his Hubsink website.
https://hubsink.com/products/genuine-st ... lian-stock
viewtopic.php?f=31&t=91204&hilit=hubsinks
I've only done about 1000km, with no ill effects (yet). Before I put it in my motor, I did read about these issues. But there are many types of FF, and many types of adhesives used in motors, so I decided to take the gamble. Time will tell.

I also limit my temps to 130C. Mainly because I spend extended time close to the limit, and I don't want to demag my magnets. 130C has worked for me so far. Plus, if temp degrades the adhesive, it's more susceptible to solvent attack.
999zip999 wrote:
Mar 26 2020 10:33am
Magnets a very brittle and must be handled will extreme care and they can jump and brake.
Good point. I imagine it's a pretty tricky job to fix a rotor once the original adhesive starts to fail (even if the magnets aren't damaged).

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by john61ct » Mar 26 2020 5:47pm

I wonder if a build-to-order manufacturer like QS / Taizhou / SIA could be persuaded to allow a specific adhesive be specified?

I'd even be willing to drop-ship it to them. . .

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by madin88 » Mar 27 2020 11:12am

DogDipstick wrote:
Mar 26 2020 10:58am
Very interesting that a product meant for "high power builds" doesn't work and cooks off and melts magnets.. on high power builds...
Generally from what i learned back then when i bought direct from MXUS factory is they do not have much interest to offer motors with a bit higher quality level than usual which would be relevant for robustness and longer lifetime. It starts with non-sealed sidecovers (they even did not want to do this up on my request when offering to pay extra for that), with the glue for magnets which obviously belongs to low quality low temp sort, and ends with cheap bearings.

Thats how the world seems to be today. More profit is made with short living cheap products especially if you look at China. With some dollar extra these companies could made these motors to live many years longer, but instead it seem what they want is to force you to buy a new one soon and then the next one.
I mean who really takes the effort to reglue the magnets or order new ones if some broke from spinning freely? Most dealers will just swap the rotor out for a new one and the old one with it's rear earth materials lands in the garbage. Or if the entire motor breaks because of water was entering?
Put in garbage and buy a new one.
You guys know, what about the MCR Toner and Peanut oil? Or the ATF? Both are something I would likely try before ferrofluid, if ferrofluid cannot even handle a mxus3K. I am about to douse my hub t0 the axle in ATF. lets see what the before/after data logs say then. :) Takes alot of temp to coke ATF from what I know.

ZOk I'll shut up with nothing to contrib... and just lurk the rest of the thread. I am sans experience.
Oil has been tried long before FF was popular. It works better, but is has more drag and it will leak out from the bearings and even from the phase wires via the free space between the single strands. Each time the temperature changes there will be a pressure difference and it will push out the oil.

The good thing about FF is that it works quite well (way better as without any cooling mods) and you can keep your motor closed and nothing leaks out.

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by goatman » Mar 27 2020 3:55pm

I run 15ml grin statorade in a hs3540r-10rpm/v at 2500 watts. at 4000?km had it open and it was like brand new inside, statorade hadn't been absorbed by the glue. after first trip of having opened it, a little statorade had leaked out the sidecover seam, so I retorqued the sideplate screws and all is fine. crystalyte glue seems fine.

I bought spare bearings for the 3540 and kept them in the statorade package. it doesn't say type b anywhere on package and was purchased last spring.

I bought a mxus xf40 high speed in a 20 inch wheel I run at about 2500 watts, after what john in cr and madden88 said I wont be putting statorade in the xf40 til I check with Grin, its a "made for grin motor" with a statorade fill port

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by john61ct » Mar 27 2020 5:23pm

great reports, thanks

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by Allex » Mar 27 2020 6:12pm

I have to fill up my leaf 35mm motor with statorade every 2-3 months, it seem to vanish(or absorbs by laminations) and also dissolve the factory magnet glue.

Info
viewtopic.php?f=30&t=66489&p=1404567&hi ... e#p1404567

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by Cowardlyduck » Mar 27 2020 7:33pm

I've used Statorade in about 5 motors now over the last ~4 years.
1)
Crystalyte HS4080 @ 7.5KW:
10ml Statoraide, Fan cooled, Large holes: Result = FF dissolved motor varnish, but not magnet glue:
DSC_3257.JPG
DSC_3257.JPG (356.3 KiB) Viewed 697 times
DSC_3258.JPG
DSC_3258.JPG (310.06 KiB) Viewed 697 times
DSC_3260.JPG
DSC_3260.JPG (280.64 KiB) Viewed 697 times
Since then, I've continued using this motor putting over 2000km on it. Fans still work fine, added more FF and it works great at 7.5KW. :D

2)
Leaf motor 35mm @ 7.5KW:
8ml Statoraide, Fan cooled, small holes: Result = FF remained and only a small amount of varnish dissolved, still relatively clean:
DSC_3892.JPG
DSC_3892.JPG (330.88 KiB) Viewed 697 times
DSC_3895.JPG
DSC_3895.JPG (344.34 KiB) Viewed 697 times
DSC_3904.JPG
DSC_3904.JPG (293.79 KiB) Viewed 697 times
Same as above, I've continued using this motor putting over 2000km on it. Fans still work fine, added more FF and it works great at 7.5KW. :D

The other motor's I've put FF in I don't many photo's of, but they have been:
3)
MXUS 3K @ 12KW:
12ml Statoraide, HubSinks:
DSC_0010.JPG
DSC_0010.JPG (387.8 KiB) Viewed 697 times
4)
Golden motor 27mm @ 1.25KW:
5ml Statoraide, Vented on one side:
DSC_2393.jpg
DSC_2393.jpg (252.03 KiB) Viewed 697 times
DSC_2398.jpg
DSC_2398.jpg (308.29 KiB) Viewed 697 times
5)
Unknown scooter hub motor with shunt modded controller @ about 500W:
4ml Statoraide:
DSC_5773.JPG
DSC_5773.JPG (382.95 KiB) Viewed 697 times
Overall my experience with Statoraide has been very positive. No magnets unstuck, and it helps cooling noticeably.
I even have good results with the opened fan cooled motor's above which was more of an experiment than anything else, but it worked well and continues to work well years after the experiment first started. :D

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by Cowardlyduck » Mar 27 2020 9:12pm

Yeah, I'll ignoring most of what was said above...I did forget to mention that my temp limits are about 130-140C on the higher power fan cooled motors.
I would set it lower, but the constant supply of fresh cool air over the windings means I can run them at higher temps without too much risk.
As a result of the fan cooling they also cool much faster and have very little thermal saturation issues, but that's a whole other separate topic thoroughly discussed over here: viewtopic.php?f=30&t=56965&start=475

The other thing I've noticed with FF is it does get flung out the cooling holes at higher RPM. After a fresh batch is added I typically spin the wheel at max RPM for a few seconds and wind up with a nice line of FF all over the place. Enough of it stay's in there to last a good while though and I'm only having to top it up once every 8-12 months even with the holes.

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by serious_sam » Mar 27 2020 11:15pm

Cowardlyduck wrote:
Mar 27 2020 7:33pm
I've used Statorade in about 5 motors now over the last ~4 years.
Thanks for sharing all that great data. I'm regularly running my MXUS3k up to 130C, in a 26" wheel, with Statorade and Hubsinks. Only done about 1000km so far. Your experience gives me some confidence that I can get a decent life out of the motor at that temperature limit.

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by amberwolf » Mar 27 2020 11:37pm

the ot posts about motors that work without ff were moved here:
viewtopic.php?f=30&t=105379

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by serious_sam » Mar 30 2020 5:48am

I'm surprised that this topic hasn't received more attention. Maybe there aren't that many FF related failures after all.

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by amberwolf » Mar 30 2020 11:08pm

something to note is that motor "overwatters" ;) over the years have had magnets come loose before ff was in use. i cant' remember which members specifically, but i recall more than a few such failures.

it has been supposed that this is from heat softening the epoxy used to secure the magnets. (and potentially from heat-cycling causing fracturing of the epoxy over time).

if that's true, then using ff would exacerbate this type of failure, becuase it directly moves heat *into* the magnets, and thus the epoxy, accelerating the softening.

once the epoxy is already soft, i expect it becomes more soluble by anything in the ff that it might be susceptible to in the first place.

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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by ZeroEm » Apr 30 2020 10:09am

Have 5ml Statorade in 1500w 2019 7T Leafmotor run @ 2600 watts max. Have 2000 miles in 10 months on it. It gets hot in the summer (not like Phoenix), the motor spends most of it's time less than 800 watts and no issues. Will be taking the motor apart this summer to fix temp sensor and will update with pics.
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Re: Some Motors Incompatible with Statorade / Ferrofluid cooling?

Post by j bjork » Apr 30 2020 12:24pm

I have 10ml statoraid in a qs 205 50h. I havent opened it, but so far no issues. I'm pretty sure mine doesn't say anything about A or B as I think the earlier batches said? I have only been riding it for a year, and mainly off road. Limiting power over 130 degrees C, I usually have around 110 degrees C after a ride.
I started with lower power, but now peaks up to almost 24kw.

It sure is an interesting topic, and I think it would be interesting to hear if people had problems without statoraid too.

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