FINALLY, got to run my Spartan

[roadrashracing]

I love running mine like that, the challange of not flipping over

[dag-nabit]

MAJOR MELT DOWN

Headed out to the lake Monday evening and arrived in time to charge up a few sets of batteries and make a couple runs before the sun set. The lake was nice and calm so I was looking forward to some WOT run time.

First run went pretty well, managed to record my best speed to date of 79.1 kph (49 mph) but death wobble was very much present at high speeds, I'm certain it is what is preventing me from breaking the 50 mph mark.

The boat handled, IMO, exactly the same without the turn fins installed as it did before I removed them, so I'm convinced they are really only cosmetic on this hull. I'm not suggesting pulling them off for no reason, but if you damage one, or don't like the look of them, try removing them to determine for yourself if you think they do anything on this hull.

The temps were a bit higher than normal after the run at 35 - 39 *C (95-102 *F) on Batteries, Motor, and ESC. Not problematic, but because they were higher than normal I double checked everything, including the stuffing tube, and everything seemed pretty consistent. I chalked the rise in temps to lots of WOT running.

I popped in a fresh set of batteries, and less than two minutes into the run the boat made a funny noise and stopped dead.

When I opened the hatch the smoke rolled out and I'm thinking I've blown the motor or ESC, but it smelled like melted plastic, not electronics.

Turned out I twisted up another flex cable (third one between two boats) and seriously overheated the stuffing tube (warped it)

Melted Stuffing Tube Clamp: The glob of spun plastic looks fairly solid in the picture but it is spun plastic strands, like cotton candy.


The clamp was fused together with the tray, had a tough time getting them apart. Also fused right onto the stuffing tube.


The Stuffing Tube Guide is Also Melted


Details on Damage to the Stuffing Tube and Flex


This Gives an Idea of the Area Where the Damage Occurred



I believe the binding was starting on the first run, causing the temps to increase a bit, then failed during the second run.

I don't see much in the Eagle Tree Data to suggest a problem, amp draw was pretty normal compared to previous runs, although my battery voltage did sag very quickly toward the end of the run.

This does confirm my 79 kph top speed. GPS Green - Amps Red - Voltage Blue



Kevin

[dag-nabit]

After twisting up another flex cable and taking out the stuffing tube and component tray with it on my Red Spartan, I decided to try running the Blue Spartan without the liner, and with the stock .150 cable.

It was like a completely different boat. Accelerated better, and seemed more stable as well with less torque roll, BUT, I can't confirm the stability and torque roll just yet because the water was too rough to go wide open throttle for more than a second or two. But it certainly seemed more stable in the rough water.

Still had a good coat of grease on the flex cable after two back to back runs, although the end nearest the collet was looking pretty much wiped clean but the lower 2/3 or 1/2 including the stub shaft had good grease on it.



I'm going to run without the liner in the stuffing tube for the next while to see how it pans out in the long run.

Temps on the batteries, motor, ESC, and stuffing tube were all between 22 - 25 *C (72 - 77 *F).

My boat is going to be shelved until I can get a new component tray, and some flex shafts from Jeff. Thank goodness for the venerable SV27, rock solid and ever reliable.

Kevin

[bdp1174]

Wow that is crazy.Did your stuffing tube still have the original teflon liner in it before it melted it or was it a newer liner?
Please keep us posted on your latest spartan adventures....

[Doug B]

How square is your 1/4" bore into the bushing on your strut? in the picture it doesnt look square, but I take lots of pictures and know that is very probably an illusion. I looked close at the drive line on mine, and decided to trim the brass tube only slightly longer than the original, and not insert it in the strut, and instead am relying on the grommet to seal out water and the associated vacuum effect.. Im just wondering if a little strut movement would be enough to add some resistance to the cable where it is sunk in the rear bushing..

Alternately, could it be the teflon liner spinning in the tube, heating to molten in places, and binding the cable? I wonder if it got hotter at the rear bracket because that area is more insulated, and the whole thing started from that?

Or I could be completely wrong.. just things that come to mind.. its interesting, I know you have all quality components in the drive line, did you notice any S bend like what WVGeo is talking about in his build thread?

[dag-nabit]

The stuffing tube and flex cable lined up pretty well. I also checked the "movement" at the clamp end with the tube high and low in the rear guide as per GeoVW72 (George) observation. I'm not saying George isn't on to something, but I didn't think the amount of movement at the clamp was significant enough to cause any real problems.

At this time, I'm leaning toward the idea that the tolerances are just too tight with the liner in the tube on this set up. Running 1600kv (stock) or 1700kv (my setup) on 6S is giving you 35 - 37K unloaded RPM, on a large hull, and a good size prop. I think there is enough torque twist on the .150 cable that it is scraping the inside of the liner, then it starts to abrade and/or rotate the liner causing heat.

In the case of this failure, if you look at the detail picture, and the picture showing the approx. areas the damage took place relative to the flex cable and tube. It would appear the cable started to scour the liner near the rear guide and then start to bind, then the shaft started to twist and bind even more. You can see the heat discoloration on the flex cable where it twisted. At this point the liner would have been spinning rapidly and would have been pinched tight against the inside of the tube causing enough heat to melt the plastic component tray.

The sequence of events is really just a guess, but that is my interpretation.

I'm going to try running liner free, at least until my new cables from Jeff arrive to see what happens. The problem may still manifest itself, at which point, back to the drawing board, but my initial observation trying no liner, was favorable.

Kevin

Note: I don't think the teflon liner is actually melting. Teflon has a melting point of around 600 *F and I don't think things are getting that hot. That said, the liner may be a teflon blend/composite of some type and could have a lower melting point.

[dag-nabit]

We had a great weekend at the lake. Had a chance to run most of our boats several times. The exception being my Red Spartan, I'm still waiting on parts after melting the component tray.


We got in 5-6 flawless runs with my daughters Blue Spartan. It was encouraging to do multiple runs with no issues. We were running with the liner removed from the stuffing tube and the drive line temps were consistent at around 22 - 23 *C (72-75 *F)

Then we "decided" it was time to prove out the question of which is stronger; plastic or fiberglass. My daughter made a wrong turn in front of my SV27 just as I was coming back on plane out of a corner, and I T-boned her Spartan.

The results:

Spartan 0 - SV27 1

Spartan suffered a good hole in the hull




The SV27 suffered some very nasty paint transfer


Kevin

[dag-nabit]

Another quick video

[Jeff Wohlt]

wOW...well I have to say it looks like fun but cables won't long with hopping at those rpms but what the hell...have fun, fun, fun. :0

[dag-nabit]

wOW...well I have to say it looks like fun but cables won't long with hopping at those rpms but what the hell...have fun, fun, fun. :0

yeah, but oddly enough, apart from the first cable that snapped less than two minutes into the maiden voyage, the (stock) cable in this Spartan has lasted the longest and is still going strong. (running without the liner in the stuffing tube)

Our cable problems seem to be related more to binding and overheating than running in rough water.

Kevin

[Jeff Wohlt]

I really wonder if these liners are PTFE/teflon or some type ofother mix. There are tons of different makes of that stuff. Only recently have we seen some of those china boats having these problems.

So you snapped the 150 I sent you but the stock is holding....had to be a liner issue or alignment.

[dag-nabit]

I really wonder if these liners are PTFE/teflon or some type ofother mix. There are tons of different makes of that stuff. Only recently have we seen some of those china boats having these problems.

So you snapped the 150 I sent you but the stock is holding....had to be a liner issue or alignment.

I agree.

I was running Octura liner so quality should not have been an issue.

I am leaning toward the theory that that the flex cable is twisting enough under load that it gets too tight in the stuffing tube with the liner installed. Removing the liner gives the flex cable some "room to breath".

Since running without the liners we have had zero problems with drive line heat or broken cables. That is not to say we won't, we have maybe a dozen runs in at most without the liners, but so far this is our best reliability. Time will tell.

As soon as I pulled the liners it was like we were running different boats, faster and more responsive on the throttle.

Keep in mind, we are pushing our boats a bit beyond "normal" running. T180 ESC and 3674 1700kv running 6S with a Prather 220 prop. That has to be putting some strain on the drive line. I'm really considering dropping back to a P215, the boat is too jittery at WOT anyway. A bit less speed would be fine for how we run, and that will help unload things a bit.

Kevin

[the5]

why do you guys drive the boats from in the water?

[dag-nabit]

why do you guys drive the boats from in the water?

Just works good for us.

Not sure if you can see it in the video or not, but there is a buoy about 300 - 350 feet offshore. the water doesn't get more than chest deep until you get out past the buoy.

There are docks and boat lifts along the shore so we need to get out past those for good visibility.

Sooner or later you have to go retrieve a boat, so we just wear chest waders and stand in the water just past the boat lifts, and if we flip we just walk out to retrieve the boat. Just easier than jumping up and down off the dock.

Kevin

[shctexas]

....and its fun!

[dag-nabit]

Yes It Is...

Kevin

[stadiumyamaha]

dag-nabit.
I havent read all your post so you may have allready done this but the number one thing I did to my Spartan was to ad a second set of the stock trim tabs. There is blind holes in the transom for mounting a pair. What it did was allow me to get higher speeds without the dead wobble. Super easy to do and the boat started to ride like a boat. JUst something Ive learned while fighting the spartan blues.
SY

[dag-nabit]

dag-nabit.
I havent read all your post so you may have allready done this but the number one thing I did to my Spartan was to ad a second set of the stock trim tabs. There is blind holes in the transom for mounting a pair. What it did was allow me to get higher speeds without the dead wobble. Super easy to do and the boat started to ride like a boat. JUst something Ive learned while fighting the spartan blues.
SY

I had ordered a couple sets for our Spartans, but only received one due to back order. I installed the extra set on my daughters Spartan when I replaced the hull following a crash. We haven't had the opportunity to run it yet so I'm not sure how much difference it will make. Some say it really helps, others say it makes no difference. If I like the results I'll make a point of ordering another set for mine.

Kevin

[stadiumyamaha]

They made a huge dif for me when at higher speeds.

[dag-nabit]

They made a huge dif for me when at higher speeds.

That's what I'm hoping for
Kevin

[dag-nabit]

I agree.

I was running Octura liner so quality should not have been an issue.

I am leaning toward the theory that that the flex cable is twisting enough under load that it gets too tight in the stuffing tube with the liner installed. Removing the liner gives the flex cable some "room to breath".

Since running without the liners we have had zero problems with drive line heat or broken cables. That is not to say we won't, we have maybe a dozen runs in at most without the liners, but so far this is our best reliability. Time will tell.

As soon as I pulled the liners it was like we were running different boats, faster and more responsive on the throttle.

Keep in mind, we are pushing our boats a bit beyond "normal" running. T180 ESC and 3674 1700kv running 6S with a Prather 220 prop. That has to be putting some strain on the drive line. I'm really considering dropping back to a P215, the boat is too jittery at WOT anyway. A bit less speed would be fine for how we run, and that will help unload things a bit.

Kevin

Talk about famous last words. Next run made on the Blue Spartan and "poof' another drive cable snapped and took out the stuffing tube and melted the component tray again. The component tray isn't melted nearly as bad this time, just enough to fuse the tubing clamp and tray together.

I'm convinced this was a failure of the OEM stock cable due to stress, not binding. I was checking temps regularly and never saw anything over 22-23 *C (approx. 75 #F) on the stuffing tube prior to the failure.

You can see in the photo the cable unraveled almost the entire length, and the stuffing tube bulged and overheated where the cable failed and parted.


And a couple close ups of the worst damaged area.




I just received my .187 cables from Jeff, and the parts I've been waiting on to fix my Red Spartan and get it back in action, so I will up fit both boats with the heavier cable and see what results we get.

Kevin

[dag-nabit]

Well I finally got the parts I needed to repair my Red Spartan, and fortunately I had ordered extras so I also had the required parts for repairing the Blue Spartan as well. I also received the .187 flex cables I had on order from Jeff. So I spent the past couple afternoons putzing around in the shop getting the Spart's ready for action again.

The repairs involved completely removing all components and replacing the melted trays in both boats, so, since I had everything stripped down I decided I might as well change things up a bit.

Motors: The most noticeable change is the absence of the orange Tacon 3674 1700kv motor swapped out for a shiny red Leopard motor and water jacket. I implanted a 4082 1500kv in the Blue Spartan, and decided to go with a 4074 2000kv motor in the Red Spartan.

I should note that there were no problems with, nor any reason really, to swap out the Tacons. They were running well and had performed impressively over the past several weeks, but foolishness and boredom are persuasive mistresses, so I decided it would be fun to experiment a bit.

Leopard 4074 2000kv Installed in the Red Spartan. Still running the T180 ESC with timing set at 0* advance.


The decision to install the 4082 1500 was pretty straight forward. This is a combination that has been run successfully by many others, and considering all the drive line issues I have been having, dropping the kv a bit might be a step in the right direction.

Installing the 4074 2000kv was a decision I wavered on several times before deciding to take the plunge, I have, after all, often recommended against going to high kv motors on this boat because of all the drive line problems that may result. It is a bit counter intuitive to increase the kv rating on the motor when you are twisting up drive cables and overheating stuffing tubes to the point you are melting component trays. But I want to experiment a bit with running lower kv and larger props on one boat, and higher kv and smaller props on the other boat to see what effect, if any, it has on the drive line, torque roll, and chine walking.

I am still trying to target a 50'ish MPH Spartan with stable, reliable, running, so going up in kv is not intended to push the speed any higher, and if Traxxas figures they can run 1800kv, why not 2000kv, after all Traxxas has made so many other well thought out and successful decisions with this boat, what could possibly go wrong??
(extreme).

I stayed with a Prather 220 on the Blue Spartan with the 4082 1500kv, and have dropped back to a Prather 215 on the Red Spartan with the 4074 2000kv motor. I have some smaller three blade props that I will experiment with as well on the Red Spartan, and some larger props I can try on the Blue Spartan if needed to stay in the high 40's low 50's range for speed.

I also installed the extra set of trim tabs on both boats to try for myself to see if they will assist with high speed stability (chine walking). The left tab needed a bit of a notch filed in to fit around the water pickup on my trim tab adjuster, but that was an easy fix.



The other modifications were installing the collet and .187 flex cable (no liner in the stuffing tube, cable won't fit with it anyway), and changed out the bullet connectors between the ESC and motor to Castle 6.5mm.

RECAP
Both Boats: New component tray, .187 collet and flex cable, 6.5mm bullet connectors between ESC and Motor, extra trim tabs.
Blue Spartan: Leopard 4082 1500kv motor, Prather 220 prop.
Red Spartan: Leopard 4074 2000kv motor, Prather 215 prop.

Hope to run them next weekend.

Kevin

[dag-nabit]

Well the decision to run the Leopard 4074 2000kv motor proved to be a bad one.

I got in 4-5 good runs with it using a .187 flex drive from Jeff and a Prather 215 prop. It was running pretty nice on this set up, fast, reasonably stable and less torque roll with the smaller prop.

But, on the next outting I fried the Turnigy 180 amp ESC.

Not certain what happened, the capacitors don't appear swollen, but it did melt 3 of the 5 wires off the ESC.

I didn't take a close up picture of the ESC but it melted down pretty good. There is what appears to be melted plastic oozing out between the circuit board and case, and there was plenty of smoke. The hull was not badly damaged, but as an added bonus it did take a pair of lipo batteries with it when it torched.

The Eagle Tree graph shows amp spikes in the 180 range, but spikes in the 170-180 range were not uncommon with the Tacon 3674 1700kv either. What I can't be certain of is if the Eagle Tree was maxed out, it is only rated for 150 amps, so the spikes may in fact have been higher than recorded.

The Eagle Tree also shows a voltage spike to 27v about 30-40 seconds before everything come to a halt. I can't help but wonder if this was caused by a capacitor popping.

Black - Volts
Red - Amps
Green - GPS






I have to wonder how the new Castle setup is going to hold up with the 1800kv motor on 6s. We don't know the AMP rating on the ESC yet, but it is highly unlikely it is anywhere close to 180AMP. I know the Castle components might be better quality and more efficient than the Leopard/Turnigy combination, but I have to say I agree with George (GeoVW72) that Spartan owners with the new Castle components should be cautious propping up very much from stock.

I had the components necessary to rebuild my boat on hand, but opted to install a Leopard 4082 1500kv motor instead of staying with the 2000kv and trying smaller props. (Both Spartans on same setup now)

The boat cleaned up not too bad but does have some lingering discoloration and smell to it. It is running good on the 4082 1500 with an Octura X642 prop, but the torque roll is more noticeable again with the larger prop.

Kevin

[dag-nabit]

Headed out to the lake yesterday hoping to get a few runs in with the Spartans. It was breezy, and the lake was pretty rough but we decided to give it a go anyway since we haven't had an opportunity run them for a few weeks.

Both are now setup with T180 ESC's and Leopard 4082 1500kv motors. I'm running an x642 prop and my daughter is running an S220 prop.

My daughter got in one good run, but I popped another ESC after about a minute of running. This ESC has only a couple runs on it with the current setup. There was no smoke, no heat, no popped caps, it just up and died. I'm convinced it was a manufacturing defect, not the setup that caused the failure.

We decided it was too rough to continue running, so shut it down after one run.

I'm down to my last T180 ESC. I was planning on setting up a separate component tray with a CC1515 motor and T180 ESC to run on 5S with a wire drive, but now I need the ESC for this tray. I think I'll change it up to try the 5S setup, hopefully all my stuff will be here in time to get some good runs in before the cold weather arrives.

I'm sending both ESC's back to Hobby King to see if they will consider warranty replacement.

Kevin

[wilsta67]

MAJOR MELT DOWN

Headed out to the lake Monday evening and arrived in time to charge up a few sets of batteries and make a couple runs before the sun set. The lake was nice and calm so I was looking forward to some WOT run time.

First run went pretty well, managed to record my best speed to date of 79.1 kph (49 mph) but death wobble was very much present at high speeds, I'm certain it is what is preventing me from breaking the 50 mph mark.

The boat handled, IMO, exactly the same without the turn fins installed as it did before I removed them, so I'm convinced they are really only cosmetic on this hull. I'm not suggesting pulling them off for no reason, but if you damage one, or don't like the look of them, try removing them to determine for yourself if you think they do anything on this hull.

The temps were a bit higher than normal after the run at 35 - 39 *C (95-102 *F) on Batteries, Motor, and ESC. Not problematic, but because they were higher than normal I double checked everything, including the stuffing tube, and everything seemed pretty consistent. I chalked the rise in temps to lots of WOT running.

I popped in a fresh set of batteries, and less than two minutes into the run the boat made a funny noise and stopped dead.

When I opened the hatch the smoke rolled out and I'm thinking I've blown the motor or ESC, but it smelled like melted plastic, not electronics.

Turned out I twisted up another flex cable (third one between two boats) and seriously overheated the stuffing tube (warped it)

Melted Stuffing Tube Clamp: The glob of spun plastic looks fairly solid in the picture but it is spun plastic strands, like cotton candy.


The clamp was fused together with the tray, had a tough time getting them apart. Also fused right onto the stuffing tube.


The Stuffing Tube Guide is Also Melted


Details on Damage to the Stuffing Tube and Flex


This Gives an Idea of the Area Where the Damage Occurred



I believe the binding was starting on the first run, causing the temps to increase a bit, then failed during the second run.

I don't see much in the Eagle Tree Data to suggest a problem, amp draw was pretty normal compared to previous runs, although my battery voltage did sag very quickly toward the end of the run.

This does confirm my 79 kph top speed. GPS Green - Amps Red - Voltage Blue



Kevin

wow that's impressive melting lol . that would actually make a nice upgrade for this boat an aluminium tray!!

[dag-nabit]

wow that's impressive melting lol . that would actually make a nice upgrade for this boat an aluminium tray!!

Agreed, I really like the concept of the component trays, one of the few things I think Traxxas got right on the Spartan, but a nice upgraded aluminum tray might be a nice touch.

Kevin

[Rumdog]

5s on a CC/Neu 1515 1y. Say goodbye to your last T-180. Why push it? Buy the correct motor. If you want to run 5s, run 1500-1800kv motor. 4s, 1800-2200kv motor. 6s, 1200-1600kv motor.
You are just setting yourself up for another meltdown. You need to understand that a 1515 is not a big enough motor for this hull. A 1520 or 1521 should be the minimum, and the proper kv to run 6s.

[dag-nabit]

5s on a CC/Neu 1515 1y. Say goodbye to your last T-180. Why push it? Buy the correct motor. If you want to run 5s, run 1500-1800kv motor. 4s, 1800-2200kv motor. 6s, 1200-1600kv motor.
You are just setting yourself up for another meltdown. You need to understand that a 1515 is not a big enough motor for this hull. A 1520 or 1521 should be the minimum, and the proper kv to run 6s.

You may well be right Rumdog, but I will likely still give it a try just for $hits & giggles. The 2200 kv on 5S will give me similar rpms to the 3674 1700kv I was successfully running on 6S, and the lower voltage on 5S will hopefully take enough load off the T180 that it will hold up. I realize amp draw will still be high, but until it is tried, won't know for certain.

I will probably make a few runs on 4S and monitor amp draw on the eagle tree before trying to run 5S.

I also have a CC1717 motor, which has a nice kv rating and plenty of torque, but I feel that motor is too heavy to run on the plastic motor mounts without some sort of tail ring support.

Kevin

[Snowride]

Well I sure am glad you are the one doing all the testing and showing me what I should not do. I may sound like a broken record but mine has just been perfect in all respects except for going through plastic props which I understand is normal. I want to thank you for showing me what to do in the beginning of all this you definately got it right. Too bad you just did not know when to stop tinkering.

[dag-nabit]

Well I sure am glad you are the one doing all the testing and showing me what I should not do. I may sound like a broken record but mine has just been perfect in all respects except for going through plastic props which I understand is normal. I want to thank you for showing me what to do in the beginning of all this you definately got it right. Too bad you just did not know when to stop tinkering.

Some of us are just slow learners....

My setup was running just fine with the tacon 3674 1700 and T180, apart from drive cables piling up. But.... every time I have to tear the tray apart I can't resist a look in the tickle trunk, nor the temptation to try something different just for the heck of it.

I know some of it is bound to fail, but what the heck, I enjoy putzing around and if others can use my experience to help them decide how they want to proceed, then, you know, that's ok too.

Kevin