I have a couple dozen flights (maybe 30?) on my beloved Scorpion SII-3020-1110 which I picked up from Innov8tivedesigns a couple years back. I originally intended to run this motor on 4s with an 8x8 prop but the motor was a bit too heavy for my Parkzone P-51 Gunfighter but it fit perfectly in my Parkzone P-47 Thunderbolt and turned this plane from a plesant parkflyer into a cloud-carving monster.

I was running the plane on 3s/4400/30c packs and a Parkzone 10x9 prop (sourced from the Extra 300), 80A Turnigy Plush ESC and an external Castle BEC (to power the retracts and flaps reliably).

While this prop isn't specifically noted in the prop chart, an APC 10x10 is noted as "safe" on 3s so I was confident that a 10x9 would be ok as well.
http://innov8tivedesigns.com/Scorpio...10%20Specs.htm

So initially, the motor "knocked" when I ran it up to full throttle. I know how bad this is for a motor so I landed immediately and set the ESC to "low" timing. This produced the same results with an occasional knock...so I tried "high" timing and it ran perfectly. This seemed odd to me but fellow club members insisted that this wasn't unheard of and that some motors needed high timing to run normally...and I couldn't argue with the results.

This motor appeared to be a match made in heaven for the Parkzone P-47...which addmittedly is like a $20 shine on a $3 pair of boots...but it's a really nice looking plane from 10 feet away...and it flies like a dream. The new top speed was impressive (probably 50% faster than stock) and the climb-outs were fantastic. I know the cliche is thrown around all the time... but with the heavy battery and the mega boost of horsepower, this plane flew "like a much larger model"

So on my first flight of the morning yesterday, I was flying my usual pattern of high speed passes, towering climb-outs, giant loops, etc...and the motor suddenly started sounding bad. I still had power but I brough it in right away with a lump in my throat.

Upon pulling off the cowl, I could see a gap at the back of the rotating portion of the motor, through which a metal ring had spewed. It also looks like at least one magnet has come loose.

Honestly, I'm heartbroken. My budget simply does not allow for another $110 motor purchase.

Is the motor a total loss? What happened? Did I cause this?

Thanks for any input!
Mike

Send a message to Lucien... He is the go to guy for Scorpion in the U.S.

You can see that part in the kits here at Go Brushless/Micro Dan:

http://www.gobrushless.com/shop/inde...w&ref=S3020KIT

Larger image - http://www.gobrushless.com/shop/medi...I_3008_KIT.jpg

I don't have a Scorpion motor and don't know what that part is. Maybe is a spacer that controls the spacing at the ends of the magnets and the bottom of the magnet housing?

Maybe an email to Scorpion might get you some consideration on the problem? Tell them what you posted and that will let them decide if there was a problem with the way you were using the motor or it it might be a warranty consideration.

Jack

Originally Posted by JimNM

Send a message to Lucien... He is the go to guy for Scorpion in the U.S.

Thanks... yeah, Lucien is the greatest...I spoke with him on the phone and he's the guy who reccomended this motor for my Parkzone P-51 hotrodding efforts.

I'm hesitant to contact him again without having enough information though. If I did something to damage this motor, I'd rather not waste his time.

Originally Posted by jackerbes

You can see that part in the kits here at Go Brushless/Micro Dan:

http://www.gobrushless.com/shop/inde...w&ref=S3020KIT

Larger image - http://www.gobrushless.com/shop/medi...I_3008_KIT.jpg

I don't have a Scorpion motor and don't know what that part is. Maybe is a spacer that controls the spacing at the ends of the magnets and the bottom of the magnet housing?

Maybe an email to Scorpion might get you some consideration on the problem? Tell them what you posted and that will let them decide if there was a problem with the way you were using the motor or it it might be a warranty consideration.

Jack

Thanks, Jack. That's definitely the part. It certainly seems plausible that the ring is used for spacing the magnets.

What holds these components in place? Some kind of epoxy?

Yeah... I suppose I should just call them. Obviously, if I caused this by means of my own ignorance, I wouldn't expect any warranty coverage.

The ring protruding from your motor IS the magnet spacer!
The magnets are glued in with some form of special magnet epoxy.
Now, I don't see any report of a Wattmeter test being done before using a 10x9 prop on 4S. Iam going to say that it would be way over maximum allowed amp rating on 4S. According to Scorpcalc, a 10x9 would require 81A on 4S. The motor is rated for 50A continuous.
The fact that it required HIGH timing is a giveaway to its max being exceeded.
Heat has melted the epoxy, moving the ring out of place. I'd send it back to Scorpion for repair, then run a 10x5 (54a) or a 9x6 max. Don't expect even a Scorpion to run at 60% over max, at least not for long. Thats whay they have a rating after all. Scorpion will treat you right if your fair with them.
I have the same motor for 4 yrs, right up to its max amp rating, mine has run lukewarm over approx 100 flights in 2 different planes. FWIW Doug B

Originally Posted by Doug Bartley

The ring protruding from your motor IS the magnet spacer!
The magnets are glued in with some form of special magnet epoxy.
Now, I don't see any report of a Wattmeter test being done before using a 10x9 prop on 4S. Iam going to say that it would be way over maximum allowed amp rating on 4S. According to Scorpcalc, a 10x9 would require 81A on 4S. The motor is rated for 50A continuous.
The fact that it required HIGH timing is a giveaway to its max being exceeded.
Heat has melted the epoxy, moving the ring out of place. I'd send it back to Scorpion for repair, then run a 10x5 (54a) or a 9x6 max. Don't expect even a Scorpion to run at 60% over max, at least not for long. Thats whay they have a rating after all. Scorpion will treat you right if your fair with them.
I have the same motor for 4 yrs, right up to its max amp rating, mine has run lukewarm over approx 100 flights in 2 different planes. FWIW Doug B

Thanks, Doug. I would agree with you that 4s on a 10x9 prop would be too much.. I was running 3s with the 10x9 though...and it should have been ok. (The 4s was going to run with the 8x8 but I never tried it). I can see that my original post was confusing. Sorry about that.

I did run it up on my watt meter last summer when I initially put this combination together... In retrospect, I should have double checked because the timing issue came up only once the plane was airborne for some reason...and I changed the timing after that. I don't believe I ran it up again on the meter after that.

I'm usually a bit more careful than this. Most of my planes have the stats written down with a sharpy inside the fuselage and keep records when I change props and/or batteries.
So... your point stands. Perhaps the timing did cause the motor to be over-amped.

So why would the motor not run properly on "low" or "mid" timing? This sounds like a Power Systems Corner question.

Overpropping is the most obvious reason. It requires a lot more power, read amps to get the prop to spin up to speed, something the motor will always try to do. It will always try to run to its kv regardless of the celll count. If you pull the motor down with too much load, the motor still tries to spin it up, amps go way up very quickly with even a little too much prop. The timing is a way of forcing the motor to accept more amps and comentate, but produces excess heat in the process.
Lucien actually recommends propping to 80% of suggested max for long life. Your 10x9 doubles that reccy. Scorpion calc states a 10x5 as max (slightly over at 54A) It may handle a 8x8 or 9x7, always test every prop change, 1" pitch can jump A 20-40% in some cases, esp when changing cell count. FWIW Doug B

Originally Posted by Doug Bartley

Overpropping is the most obvious reason. It requires a lot more power, read amps to get the prop to spin up to speed, something the motor will always try to do. It will always try to run to its kv regardless of the celll count. If you pull the motor down with too much load, the motor still tries to spin it up, amps go way up very quickly with even a little too much prop. The timing is a way of forcing the motor to accept more amps and comentate, but produces excess heat in the process.
Lucien actually recommends propping to 80% of suggested max for long life. Your 10x9 doubles that reccy. Scorpion calc states a 10x5 as max (slightly over at 54A) It may handle a 8x8 or 9x7, always test every prop change, 1" pitch can jump A 20-40% in some cases, esp when changing cell count. FWIW Doug B

I hear what you're saying here, Doug... but if we're talking 3s (and that's what I was flying), I'm 99% sure that the motor should be ok.

Am I reading the chart wrong? The 10x10 (one inch more pitch than what I was running) pulled 52.9A... granted, that doesn't take my "high" timing into account... but still, it shouldn't have been way out of the ball park...right?

Mike

The high timing will normally increase the current draw and RPM, the lowest timing will decrease both, the middle or default is where most motors are rated at or specs are determined.

Some smarter ESCs (Castle Creations for example) will let you change a timing setting but normally there will be little difference or advantage over using the automatic timing setting. That senses the loads and reactions and picks a point that is better you can find by the seat of the pants impression.

If you could get the parts (replace the ring if necessary and any damaged magnets) you could repair the motor yourself. It would entail stripping or cleaning the glue residue away, and gluing them in place again

Here is one of the World's Best Motor builders, Dr. Ralph Okon, bjuildling and reviewing your motor:

http://www.scorpionsystem.com/buildi...ld_and_review/.

Jack

Originally Posted by jackerbes

The high timing will normally increase the current draw and RPM, the lowest timing will decrease both, the middle or default is where most motors are rated at or specs are determined.

Some smarter ESCs (Castle Creations for example) will let you change a timing setting but normally there will be little difference or advantage over using the automatic timing setting. That senses the loads and reactions and picks a point that is better you can find by the seat of the pants impression.

If you could get the parts (replace the ring if necessary and any damaged magnets) you could repair the motor yourself. It would entail stripping or cleaning the glue residue away, and gluing them in place again

Here is one of the World's Best Motor builders, Dr. Ralph Okon, bjuildling and reviewing your motor:

http://www.scorpionsystem.com/buildi...ld_and_review/.

Jack

Great information...thanks. Dr. Okon's link was interesting. I'll have to go back and look to see what he did differently when building his motor but he's pushing it way beyond what Innov8tivedesigns reccomends. I have to admit that my clumsy fingers and variable level of patience are making me lean towards having this motor professionally repaired...but looking at that build,it does look interesting and fun to assemble your own motor.

So I sent a note out yesterday. I'll pass along what I hear.
Thanks again for all in the input. You guys are the best.

Originally Posted by jackerbes

... Maybe is a spacer that controls the spacing at the ends of the magnets and the bottom of the magnet housing? ...Jack

Correct. Not a structural load bearing component.

Originally Posted by MRGTX

... Dr. Okon's link was interesting. I'll have to go back and look to see what he did differently when building his motor but he's pushing it way beyond what Innov8tivedesigns reccomends. ...

Ha, you should read Ralph's posts in the High Performance subforum (user scorpion-fan) More Scorpion rewinding/abusing on Ralph Okon's site.
www.powerditto.de

Vriendelijke groeten Ron
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Ralph Okon, and his merry gang of amp-abusers, testing a motor with a 5-bladed folder

Testlauf 5 Blatt Powercroco-Treffen 5.3.11 (0 min 35 sec)

Thanks to all for the input and advice.
I sent a note to www.innov8tivedesigns.com and received a detailed response with some theories as to what caused the problem but the bottom line is that they need to look at it. So I'm sending the motor back in. The rates for repairing the motor are fair.

I don't remember the exact terms of the warranty...but I don't think it matters becayse I'd be surprised if the failure wasn't related to my monkeying with the timing and therefore, my fault.

What puzzles me is why it wouldn't run on "normal" timing....but I can't help but think that this must be a problem with the Turnigy Plush ESC...but could a cold solder joint manifest itself in this way? I did a careful job on the connectors...but soldering isn't my forte...I guess it's possible that there is a "mechanical only" connection in there somewhere that I didn't see.

Has anyone else ever had/solved this problem?

HI Mike,
Not the same thing but I have three Scorpions S1 all with T Bird 54's.
All share the same issue on initial power up where they "grind"
and stutter for a couple of seconds but after that, no problem
at all even at null throttle. It seems like there are just instances
where not all speed controls are compatible under all conditions
with all motors.

Another thing with these motors is they meter at much more current
draw and watts in than the prop chart indicated. The performance and
reliability has been tops though.

Good luck.
John

fwiw the max amp rating on that motoris 60amps continuous. the scorpion calc the one guy was referring to is admittedly (by the designer fourdan,1 smart cookie) overly cautious on amp ratings, purposefully. i have 5 different flavors of scorpion motors but, my sii 3020-1110 is the most versatile of them all. and like the man said the 80% rule is a must for cheap equipment and a smart mans plus on good equipment don't break the 80% rule and a scorpion won't ever burn a wire, demagnatize anything, with the exception of the occasional bearing you'll be able to give that 3020 to your grand babies grand babies.

yeah preach over

hey jack how you been¿

btw - i noticed lucien updated his prop chart to something more realistic. it used to give voltage @ 10.5v. yeah right now he and a very few others are showing something a little more realistic, 11.1v yeah right 11.1 volts is what a responsible lipo user calls "below the 80% rule" 11.24v is absolute stop now voltage. lets see some real readings from 12.6 - 11.9 so you can really see what's up with your watts up. a cheap zippy or blue lipo might not impress you but you stick a good hyperion or billowy or thunder pro lite on there and ...uh oh said i was through preachin already,
sorry