Help Please, Nitro Conversion Problems
01-13-2016, 04:17 PM
#1
Help Please, Nitro Conversion Problems
Hello, I just finished up converting an old HPI nitro mt to electric. I put a quicrun 1060 ESC on it and just an old traxxas brushed motor I had laying around. The motor lasted about 2 minutes and just died. I assumed at that point it was just typical of a Traxxas motor and ordered a Reedy Radon to replace it. Well, same result, 2min then DOA.
When doing the conversion I fabricated a mount out of 1.5" steel angle and I'm starting to suspect that being steel (ferrous) that the magnet in the brushed motors are some how being affected?? or is my esc burning these poor little motors??
I'm running a 35C turningy 2S Lipo if that matters.
Please help,
Mike
When doing the conversion I fabricated a mount out of 1.5" steel angle and I'm starting to suspect that being steel (ferrous) that the magnet in the brushed motors are some how being affected?? or is my esc burning these poor little motors??
I'm running a 35C turningy 2S Lipo if that matters.
Please help,
Mike
01-14-2016, 03:19 AM
#2
Bump
01-14-2016, 04:40 AM
#3
I would say severely mis geared just a guess. You don't mention if the motors were hot and or smoking. My suggestion is go with a slow brushless setup. Brushless is so much more efficient than brushed. AKA less heat produced. Which HPI is this?
01-14-2016, 09:28 AM
#4
It did not run hot, only made 2 laps around the yard and it was cool to the touch.
Its an HPI nitro rs4 mt1 with the stock spur and 15T mod1 pinion
Its an HPI nitro rs4 mt1 with the stock spur and 15T mod1 pinion
01-14-2016, 05:36 PM
#5
B
01-15-2016, 08:09 PM
#6
I wonder if your ESC is doing something funny? You dont have another brushed speedo to check to I take it?
For the motors did you pull the brushes? Really hard to break a motor in 2 minutes - even with the wrong gearing and getting it hot. Even getting them hot will usually just ruin brushes, comm, and bearings which is fixable and would likely still limp along or just make alot of noise (unless the windings are shot somehow like the insulation was damaged)
I am assuming that the ESC wasn't turning off and going into heat protection mode? ESC running nice and cool?
Some good tips here - usually a esc cant break a motor - but a bad motor can break an esc.
http://holmeshobbies.com/info/brushe...oubleshooting/
I just finished my conversion recently as well and I would vote for a cheap brushless system as well - performance boost should be big. Your probably into your esc for pretty cheap and it sounds like investing in another brushed motor is a risk. I did mine with all hobbyking stuff and it runs like a champ!
http://www.rctech.net/forum/monster-...l#post14349768
Fortunately the TMAXX is a more popular conversion so I had some reference material to build upon but that being said I am still playing around some with the gearing and how I use the turbo and boost - - - but way worth it to chuck the nitro motor and just plug n play.
For the motors did you pull the brushes? Really hard to break a motor in 2 minutes - even with the wrong gearing and getting it hot. Even getting them hot will usually just ruin brushes, comm, and bearings which is fixable and would likely still limp along or just make alot of noise (unless the windings are shot somehow like the insulation was damaged)
I am assuming that the ESC wasn't turning off and going into heat protection mode? ESC running nice and cool?
Some good tips here - usually a esc cant break a motor - but a bad motor can break an esc.
http://holmeshobbies.com/info/brushe...oubleshooting/
I just finished my conversion recently as well and I would vote for a cheap brushless system as well - performance boost should be big. Your probably into your esc for pretty cheap and it sounds like investing in another brushed motor is a risk. I did mine with all hobbyking stuff and it runs like a champ!
http://www.rctech.net/forum/monster-...l#post14349768
Fortunately the TMAXX is a more popular conversion so I had some reference material to build upon but that being said I am still playing around some with the gearing and how I use the turbo and boost - - - but way worth it to chuck the nitro motor and just plug n play.
Last edited by sacmiata; 01-15-2016 at 08:24 PM.
01-15-2016, 08:40 PM
#7
Im not good on this stuff, but i know that "put a brushless motor on it" doesn't answer your question regarding the problem you have. I'll offer you my thoughts, take it or leave it.
It's my opinion that using a ferrous metal as a mount was a bad idea. I cant help but think that you might have de-magnetized the stator, even if you didnt under gear it. Overheating raises the probability of demagnetization, and thats why people tell you to keep temps in check.
I think the ferrous metal probably exerted a greater magnetic force than the stator was capable of, causing it to demagnetize. Granted it wouldve had to have been one hell of a magnetic field, but i think its possible nontheless. Add in even an elevated tempurature (assuming you are at least a LITTLE undergeared, and i dont think its too far fetched to come to this conclusion.
At the very least, here is some more food for thought; Have you ever seen steel or iron motor mounts? I've only ever seen aluminum or wood (plane guys have a tendency to do this) used to mount a motor. Maybe thats the reason?
Just my $.02 Good luck
It's my opinion that using a ferrous metal as a mount was a bad idea. I cant help but think that you might have de-magnetized the stator, even if you didnt under gear it. Overheating raises the probability of demagnetization, and thats why people tell you to keep temps in check.
I think the ferrous metal probably exerted a greater magnetic force than the stator was capable of, causing it to demagnetize. Granted it wouldve had to have been one hell of a magnetic field, but i think its possible nontheless. Add in even an elevated tempurature (assuming you are at least a LITTLE undergeared, and i dont think its too far fetched to come to this conclusion.
At the very least, here is some more food for thought; Have you ever seen steel or iron motor mounts? I've only ever seen aluminum or wood (plane guys have a tendency to do this) used to mount a motor. Maybe thats the reason?
Just my $.02 Good luck
01-15-2016, 08:47 PM
#8
Oh yea, and put a brushless on it while your at it.....
Actually all joking aside, i wouldnt do that to that particular truck. That MT is 15 years old, and while it was a good truck, it was never really known for having a strong drivetrain, like most HPI's of the era. It was made for a .15FE engine after all, which was as gutless as they came. You'd probably break the drivetrain to pieces using a brushless motor. Stay on 2S and a 12-17 motor and it will probably stay together
Actually all joking aside, i wouldnt do that to that particular truck. That MT is 15 years old, and while it was a good truck, it was never really known for having a strong drivetrain, like most HPI's of the era. It was made for a .15FE engine after all, which was as gutless as they came. You'd probably break the drivetrain to pieces using a brushless motor. Stay on 2S and a 12-17 motor and it will probably stay together
01-16-2016, 07:23 PM
#9
All a brushed esc does is regulate DC power. Wanna check a brushed motor, just touch the leads to a nihm battery. If a steel mount affects this, then why is a brushed motor encased in steel? I had a HPI MT, fun trucks by the way. I know how much they weigh and imo putting a brushed motor in one, is a lesson in futility. Brushless are MUCH more efficient, something like 98% efficient, brushed is way less than that, alot lost in generating heat. AND they can be tuned via the esc, they don't have to be balls to the wall. Good luck.
If you insist on staying brushed use a Traxxas 775 Summit motor.
If you insist on staying brushed use a Traxxas 775 Summit motor.
01-16-2016, 07:39 PM
#10
Thank you all so much for the replies, I re-fabricated a mount out of aluminum and all is well. I've run the truck for about a whole pack and the temps are down and running like a champ.
I do plan on using brushless in the future, just doing this conversion out of spare parts to see if I even like it. So far , so good though
I do plan on using brushless in the future, just doing this conversion out of spare parts to see if I even like it. So far , so good though
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