Spartan, tear it down to build it up

[GeoVW72]

Well half the lake thawed out, cold water should help right?
ambient temp was 38*f

Run #1: stock packs off peak; yawn, too slow, ran for 5 min then brought in to change to 4s
esc: 50*f motor: 65*f

Run #2: 2x 2s 5400 40c orion revo packs; good fun, safe for the system, no leaks
esc: 55* motor: 70*

Run #3: 2x 3s 4700 45c orion revo packs; never topped them off after they were in my revo for 7min. Fast as it should be, pic was after run, jacket clearly leaking.
esc: 70* motor: 123*


Youtube Vid

Run #4: 2x 3s Brick; Fast, everything seemed fine then...

Youtube Vid
Villain is a friend's, shortly used as the rescue craft.
esc: 70* motor: 215*
receiver thermal had kicked in, not that it meant much.

Not sure how the spartan ever did what they say it should.

Dissection:
Motor was locked tight, easy to see why;




My theory on the stuffing tube liner seems bunk at this point. Sheen was still on the outside of the liner, Inside was matte, no true damage or deformation though. Oil is inadequate for 6s operation.

Jacket leaks horridly as we all know. One thing that I noted was the water seemed to pulse slightly on the outlet. I'm not sure that the fault lies in the rudder, more the outlet. Least my rudder had the pick-up running to the front of the blade, not through. I think the design of the jacket is wrong, requiring the water to flow completely around the motor causes too much restriction and I question weather the jacket is ballooning or forced cross flow is occurring to cause the stream to pulse.

One other thing I noted was an uneven wear pattern on the front of the shaft stub.




The cable also looked like it had a small kink, not enough to cause concern though. Chucked the shaft stub in a drill and ran over the whole thing with polishing compound.

Synopsis:
Why did I do this; to prove that this boat has a snowball's chance in hell of working on 6s under the best of conditions. I like experiencing failures first hand because I am in control of the variables. The only way I see this boat doing 50+ for 20min stock is down one long ski slope.

My recommendation to anyone looking to run a spartan on 6s right now
(4s seems fine enough to me until traxxas produces the fix);
Find some good marine grease; Aquacraft, Pro Boat
Attempt to find a better cooling jacket preferably a can and o-ring type
Get larger line(3ft will do or Pro boat), drill out the transom(~1/4" for larger line) and drill out the outlet(1/8" seems doable)

Currently working on the modifications, stay tuned

Tear it down to build it up

[JPriami]

Traxxas just removed this. I was reading it. Then poof gone.

[GeoVW72]

Yep, that's why it's here as well, don't really see how I'm bashing their product

[wilsta67]

Yep, that's why it's here as well, don't really see how I'm bashing their product

haha good one! traxxas just dont want to admit they have designed a lemon

[kjohnsiii]

Is there a OSE water jacket that will fit the spartan motor?

[Brushless55]

"The only way I see this boat doing 50+ for 20min stock is down one long ski slope."

That is Awesome!

Traxxas just removed this. I was reading it. Then poof gone.

And again the modtrolls take lame action

haha good one! traxxas just dont want to admit they have designed a lemon

I have really lost a lot of respect for Traxxas
to me it seems money is much more important than anything else to them

[Brushless55]

put this up on RCU
Lots of viewers there

[GeoVW72]

Is there a OSE water jacket that will fit the spartan motor?

anything for a 540 or 36mm motor, people bought up most of the longer xl s. not sure length is really critical, but it can't hurt

[kjohnsiii]

Thanks.

[shctexas]

Thats exactly what happened to mine; hence, my renaming the boat Albatross.

[Make-a-Wake]

How about the "Spruce Goose"................Howard Hughes failed attempt at a huge waterplane.............

[GeoVW72]

Hmm...Lucky golden poo maybe

I think if traxxas had their way the boats would be in a dump next to the atari E.T. cartridges. Notice how we have to look for their "award". The product has had so many stumbling blocks; esc, name lawsuit, motor. I think that they're looking at one big RED number and waiting to be pulled into black before they put out more into the fix.
They're shutting up and waiting until people buy it then they'll advertise it again with the fix
The weather's been bad so I've been looking into what I can on the bench; there may be some truth in the rumor that the motors were produced to the wrong spec.
looking around 1700kv and we all know how bad 1600kv looks.


Traxxas...I know you're out there, just because it's not on your forum doesn't mean it doesn't exist

[Brushless55]

Hmm...Lucky golden poo maybe

I think if traxxas had their way the boats would be in a dump next to the atari E.T. cartridges. Notice how we have to look for their "award". The product has had so many stumbling blocks; esc, name lawsuit, motor. I think that they're looking at one big RED number and waiting to be pulled into black before they put out more into the fix.
They're shutting up and waiting until people buy it then they'll advertise it again with the fix
The weather's been bad so I've been looking into what I can on the bench; there may be some truth in the rumor that the motors were produced to the wrong spec.
looking around 1700kv and we all know how bad 1600kv looks.


Traxxas...I know you're out there, just because it's not on your forum doesn't mean it doesn't exist

[GeoVW72]

dead motor is on it's way to traxxas
got some mods done




outlet drilled out to 1/8"
OSE 55mm jacket
large line
drilled the transom out to 1/4", more than enough for large line, added bulkhead fitting
lubed with proboat grease
strut was shifted back and set level

ambient temp was around 50*f

Run #1: 2x 2s
esc: 60* motor: 98*

Run #2 2x 3s Youtube Vid
esc: 70* motor: 158*

attempted a third run, receiver had an over temp signal on first plug in, rearmed and it was fine. arming tones were weaker, this motor may be on it's way out as well. dead packs

went through it at the shop and noticed some of the things that JPriami had going on with his stuffing tube. No discoloration, just black "shavings"

Cleaned it with motor spray, shop towel, and drill


Not sure I'm doing the bench kv calculations right
running the eagle tree in live mode with a brushless rpm sensor:
13,950rpm 5A 16.1v(4s) = 866kv
20,950rpm 6A 24.1v(6s) = 850kv
if it's off by a factor of 2 = 1700kv apparently

[GeoVW72]

more tweaks


mounted the rudder onto the other side of the bracket to increase depth of the pick-up.
traxxas 2075 servo to hold better
loosened the strut mounts and pushed it up and to the right(can only be done just slightly) added one degree of positive on the strut to air out the prop
with JPriami's issues and what I've seen of the stock liner, installed an octura liner



cleaning the cable out also helps, not sure where the gunk keeps coming from. any chance the assembly lube is still stuck in there

ambient 35*f

Run #1: 2x 2s
esc: 50* motor: 85*

Run #2: 2x 3s
esc: 60* motor: 135*

Octura liner works great so far , greased liberally, still had the sheen on the interior bore with zero signs of wear, where as the traxxas has shown obvious wear throughout.
Handling was changed with the rudder mounted differently, hooks hard when turning left, but throw was also changed. easy mod, so I leave it to personal preference. more flow isn't a bad thing though

[Brushless55]

I dought there is any assembly lube used on these shafts
but do use a high quality grease
all grease will discolor some

[GeoVW72]

well, chalk another one up
esc has started the "flutter" and the motor's lost it's poles

ambient 45*f

Run#1: 2x 2s
esc: 50* motor: 98*

Run# 2: 2x 3s
esc: 70* motor: 123*

Run# 3: 2x 3s
esc: 99* motor: 165*-188*
5 min into run 3, running straight and it just starts the flutter.
Bring it in and take the temps, 10 sec later the receiver starts the over temp blink and the motor temp rose to the second reading.
Waited 10 min for things to cool down then sent it back out to make sure it wasn't a fluke, it wasn't

Dissection:
Motor has no feel of the poles

A few black fiberglass strands were floating around the can, not 100% sure where they came from, seems around the rotor caps
bearings are ok, rear is smooth, front feels a little dirty, both were lubed with Boca grease
motor smells strongly of burnt electronics, no apparent damage to windings, maybe the epoxy cooked

Flex is fine, lubed liberally with Pro boat grease, sheen still on the interior and exterior of the liner. The stub shows some odd wear patterns though

esc shows no damage, not that much can be seen.
temped everything;
heat-sink: 99*
caps: 110*
motor wires: 101*
batt plugs: 122*

Conclusion:
Running around 7 minutes on the set up is the limit before the components are heat soaked, motor damage due to heat may have contributed to the event based on the fact that the arming tones were not as they previously had sounded.

Next step:
Test y-ing the line to reduce motor temp, explore consequential outlets and pick-ups......after things come back from traxxas

[GeoVW72]

Got a motor back from Traxxas, mostly in one peace.



other things of note



Stator wrap missing so bad that you can see the outside of the can.
and



Motor shaft also had set screw mount marks
Try, try again.
Have the Y-ed set-up ready to go



Results tomorrow

[GeoVW72]

looks good, so far
got the eagle tree installed

ambient: 32*f

Run #1:
2x 2s 5200 40C
Time: 12 min
Max speed: 25 mph
Max amp: 45
Esc: 54* Motor: 70*

Run#2:
2x 3s 4700 45C
Time: 6 min
Max speed: 45 mph
Max amp: 103
Esc: 70* Motor: 125*

Run#3:
2x 3s 8000 20C
Time 11 min
Max speed: 45 mph
Max amp: 115
Esc: 90* Motor: 125*

Eagle tree got me excited when I first downloaded the run, listed the max as 54 mph , but then went through the playback and towards the end the data went funky because of the water in the hull.
I really hoped that the 8000mah packs would get the mythical 20 min run time, but you're going to need twice that to even scratch it

To recap set-up; turn fins squared up with the hull, trim tabs level, strut level for this run, batteries mid-front CG around 25%.

[dag-nabit]

Just curious if you got a reading for average amps.

The max amps are well within the 300 amp burst rating of the stock ESC, but I'm wondering how close the average amps are to the 80 amp continuous rating for the stock ESC.

Kevin

[GeoVW72]

Just curious if you got a reading for average amps.

The max amps are well within the 300 amp burst rating of the stock ESC, but I'm wondering how close the average amps are to the 80 amp continuous rating for the stock ESC.

Kevin

I didn't download the data after every run, so it was one long stream, have to play with the software some and see what I can make it do.
Watching the play-back 60~80 was around the average which is where I think they came up with the rating.
300 is way out there, I think that's just what they could run until it blew.
ie. the way out hp # for 5 sec.

[Brushless55]

Just curious if you got a reading for average amps.

The max amps are well within the 300 amp burst rating of the stock ESC, but I'm wondering how close the average amps are to the 80 amp continuous rating for the stock ESC.

Kevin

Just to get an idea
on run #3 with 8000mah packs for 11min run down to 20% would come up at about 35amps cont.
run #1 would be about 21amps cont.
run #2 would be about 38amps cont.

[dag-nabit]

Just to get an idea
on run #3 with 8000mah packs for 11min run down to 20% would come up at about 35amps cont.
run #1 would be about 21amps cont.
run #2 would be about 38amps cont.

Thanks Brushless,

Well within the "rated" limits of the ESC, which serves to further confirm everyone's suspicions that the ESC problems are quality related, rather than it being undersized for 6S setup.

Kevin

[GeoVW72]

Brushless55:
I agree that the math is correct for the average amp consumption throughout the run, but is not the average amp load on the esc.
I will work on presenting the data in support.

dag-nabit:
All of traxxas's esc are suffering from the same quality issues. Based on the fact that they changed the esc from the prototype, I think it is speced well, but we all know the motor is not up to the task.
That is one of the major roots of the issues. The motor is under speced and inefficent so it generates heat that isn't carried away by the cooling system. That translates into a higher amp draw on the esc and a higher esc temp, that in the standard series loop transmits and compounds to the motor issue until the system melts down.
Around 7-10 min as far as I've found out

More data and better presentation tomorrow

[Brushless55]

Brushless55:
I agree that the math is correct for the average amp consumption throughout the run, but is not the average amp load on the esc.
I will work on presenting the data in support.

More data and better presentation tomorrow

average amp consumption is average amp load

[GeoVW72]

not perfect, but I have graphs

ambient: 38*f

Run# 1: 2x 2s shoved the packs all the way back
Esc: 54* Motor: 70*
Speed: 30 mph


Run# 2: 2x 3s started with the packs back, then moved them forward
Esc: 70* Motor: 100*
Speed: 44

YT Vid is after I moved the packs up

Run# 3: 2x 3s
Esc: 94* Motor: 127*
Speed: 45

YT Vid

I tried to create an amp spike by launching from a dead stop, but the esc seems to have a current limit or soft start
ESC temp is a little concerning, as the last one failed at 99*, but what concerns me more is the temp of the caps.

I've seen temps of 140-160*f on the caps of this esc and being that traxxas has potted and sealed them so they don't blow, I wounder what temp they will go thermo-nuclear at.
May have to add a cap board to help the fixing

Commence more tweaking

[Brushless55]

You have a peak of 122amps, that is not a soft setting, that sounds norm..

[JPriami]

Nice work Geo

[Brushless55]

Nice work Geo

I agree, and I think this is the first real readout on the stock motor..

[shctexas]

Ok, fresh stuff in boat 4082 1450kv seaking, 180 amp esc, in hull h20 pick-up and x645 prop. 43 mph before prop 49+ after prop....yikes! I can't imagine 58mph but I'm gonna try to get there. There's some pretty serious torque roll when you nail-it; not quite as dramatic when power is rolled on. All in all a success