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Is 205°F too hot for a TrailMaster Sport?

fyrstormer...

You talk a good game Re: electronics, but the fact remains - you made this statement:

"So yeah, if anyone was wondering whether a TrailMaster Sport 550 21T is up to the task of moving a 9-pound TRX-6, the answer is "no"."

Only after that did you clarify - by adding "(at least, not on 2S.)"

After that you continues in the same vein - "I'm a little concerned that any 550-size brushed motor will be overwhelmed....(snipped as irrelevant to this conversation)"

And more:

"In any event, the moral of the story is: If you're going to run a motor in a high-torque/low-rpm setup, make sure it's a premium motor with the strongest magnets you can get, not a disposable motor with cheap magnets. If the armature doesn't have strong-enough magnets to push against, it will behave like an electric heater instead of an electric motor. I already knew this, but somehow I was still surprised by the result of this test."

You mention the model of a motor in a thread title, and then disparage its quality - yet you are misusing it by not following the manufacturers recommendations.

Let's dig in a bit here - stock TRX-6 gearing is 45t spur, 11t pinion.

You stated you were running a 39t spur, and a 20t pinion?

Nothing higher than 39/15 is recommended by the factory - and, sure - I know ignoring factory recommendations is what most of us do, especially when swapping in a motor that's likely a bit stronger - but you went WAY down the gearing chart (shown below)... and yet stuck with a 2S LiPo?

Sheesh.

Whatever.

I'll choose to ignore anything else you say about electronic anything, based on that behavior. You ought to be very happy if the Trailmaster Sport spins up for you after that treatment, and stop slagging its performance since you treated it like absolute shit.

Very well said. "Like"
 
fyrstormer...

You talk a good game Re: electronics, but the fact remains - you made this statement:

"So yeah, if anyone was wondering whether a TrailMaster Sport 550 21T is up to the task of moving a 9-pound TRX-6, the answer is "no"."

Only after that did you clarify - by adding "(at least, not on 2S.)"

After that you continues in the same vein - "I'm a little concerned that any 550-size brushed motor will be overwhelmed....(snipped as irrelevant to this conversation)"

And more:

"In any event, the moral of the story is: If you're going to run a motor in a high-torque/low-rpm setup, make sure it's a premium motor with the strongest magnets you can get, not a disposable motor with cheap magnets. If the armature doesn't have strong-enough magnets to push against, it will behave like an electric heater instead of an electric motor. I already knew this, but somehow I was still surprised by the result of this test."

You mention the model of a motor in a thread title, and then disparage its quality - yet you are misusing it by not following the manufacturers recommendations.

Let's dig in a bit here - stock TRX-6 gearing is 45t spur, 11t pinion.

You stated you were running a 39t spur, and a 20t pinion?

Nothing higher than 39/15 is recommended by the factory - and, sure - I know ignoring factory recommendations is what most of us do, especially when swapping in a motor that's likely a bit stronger - but you went WAY down the gearing chart (shown below)... and yet stuck with a 2S LiPo?

Sheesh.

Whatever.

I'll choose to ignore anything else you say about electronic anything, based on that behavior. You ought to be very happy if the Trailmaster Sport spins up for you after that treatment, and stop slagging its performance since you treated it like absolute shit.

What! come on Durok you cant say that he's an engineer which makes him correct all the time🤣
 
I don't think it's a challenge your after here fyrstormer. Durok makes a good point, and now you seem like the next door kid from Toy Story, who just likes to destroy stuff. Which is cool... But when you come in here saying this motor won't do this, your throwing shade on where it doesn't belong. A trailmaster sport is more than capable of of powering a trx-6, but it can't perform miracles, all of these motors have a limitations that the manufacturer has clearly stated and you have clearly exceeded. If you want to test and share that its great, but maybe clarify that.
Douglas Adams said:
"a common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools"
:)

fyrstormer said:
At this point, I suppose my only real question is whether a 5-pole motor can inherently handle a heavier workload than the same-size 3-pole motor.
The larger motors will handle a heavier workload while running cooler, but your pushing their limits too. They have a larger surface area to dissipate more heat. With the extra torque they also bog down less resulting in less wasted energy. Perhaps consider investing in a air cooled heat sink if you insist on continuing with the current voltage and gearing, or perhaps a brushless motor that is more efficient with more torque. With a brushless motor you can increase the kv and reduce the gearing giving you good low end control. Probably better than what you have now. This is because if the crawl master is twice as good on the slow startup, but the brushless is twice is fast on the top end, it gets nulled by halving the pinion size. but you net more torque and a cooler motor.

Adam Savage said:
"The difference between screwing around and science is writing it down."
 
Wow, still with the angry people. Gotta love those short autumn days and the zillion different ways they mess up people's heads. That's why we have so many holidays clustered into this part of the year, so people don't just start murdering each other.

It wouldn't be the first time something I wrote was read by someone else who then responded "Are you saying [insert worst possible interpretation of what I said]?!?!?" Someone once told me that I translate into text worse than anyone else they ever met, but I think that's because people can't help inferring emotional content in writing, and with me there is none. My father is a lawyer and I learned to write the way he does. I mean exactly what I say and nothing else.

- - -

The Trailmaster Sport is definitely a cut above most disposable motors, but it's still a disposable motor. Even when I first got into the hobby and I had no experience with premium brushed motors or brushless motors, I was still underwhelmed with the performance of disposable motors. The magnets are just not good enough. I have a couple Trailmaster Sport motors for running in vehicles that I loan to kids, but for my own use, they don't have enough torque and they run too hot -- at least in my vehicles. However, I magnanimously grant other people permission to like those motors if they still want to. ;-)

- - -

On a different note, I was outside a little while ago driving my SCX10 II, marveling at how just raising the bumper only 4mm could make the truck handle obstacles so much better, and I had a bit of a Come to Lucifer moment. I said before that I want to run my entire RC fleet using the same batteries, and that is true, but there's another motivation, which is simultaneously a goal and a constraint. But before I tell you what it is, I have to bore you with a story:

In my senior year of high school, I had the opportunity to attend a magnet school for science and technology. The classes were college-level, which was overwhelming after 11 years of public school, but the projects were super cool. I got to do biology stuff with DNA, I got to use lasers to make holograms (I was the first student in the school's history to actually succeed in making a plain-light hologram with the donated secondhand equipment the school had), I got to participate in a hacking competition, and I got to build a bridge out of popsicle sticks. That last one sounds pretty lame by comparison, but it illustrates something about my personality. While building the bridge, I insisted my team use a different design than everyone else, with the support structure under the roadway instead of above it, so we wouldn't have to design big holes into the support structure to accommodate the hydraulic press used to test the bridges at the end. The other highly-motivated guy on the team who thought I was full of crap said that he would never listen to another thing I said if we lost. I agreed. I further irritated them by bend-testing every popsicle stick in the box, throwing away any that were slightly weaker or showed a tendency to twist when bent. And I irritated them even more by weighing the 2-part epoxy to ensure a consistent mixture, and mixing a new batch of epoxy every time we took a break from gluing together popsicle sticks for even a few minutes. As the project went along, I noticed other teams starting to copy our methods. ;-)

After all that, we must've won, right? Nope. We came in second place, and there was no prize for second place. But the contracting company that hosted the competition pulled us aside to congratulate us on two things they never thought to give awards for: Our bridge was only 1% over-budget for materials and construction, and whereas everyone else's bridges crumpled when overloaded, our bridge exploded -- all of the joints were so well-matched for strength that there was no single weak spot that broke first. I was thrilled, and the other guy was reasonably content as well.

Everyone builds an RC with some kind of superlative in mind -- they want it to be the fastest, or the lightest, or completely custom-made, or whatever. My superlative is I want my RCs to be the most thoroughly adequate. That sounds boring as hell, doesn't it? But it's actually a huge challenge. It means making sure an RC is balanced in all aspects of its design. When I drive one of my RCs, I want to know that the motor, the suspension, the chassis, etc., are all being stressed equally. Partly that's because I don't want to know that the vehicle could be handling a much rougher beating if only it didn't have that glaring weak spot that I neglected to improve, but also it's because well-balanced systems are much less likely to break in the first place.

Too much weight can destroy a motor, but too much motor can destroy a drivetrain. It's better to have just enough motor, just enough suspension articulation, just enough weight on the axles, just enough battery power, etc. That way nothing gets pushed past its breaking point. The reason the topic of this thread was funny to me is because it illustrates what happens when I don't make sure everything is balanced.

Yes, I know my personality is not a good fit for this segment of the hobby, where overbuilding and overpowering everything is the norm. Deal with it. :)
 
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3S isn't going to happen because I don't own any 3S batteries and don't feel like buying them just for one truck.

I had that same stubborn mentality for a long time. Eventually I came around and decided to build a Slash with a 1/8 electronics to run on 3S. Since then, I've converted almost everything I have to 3S. It's a substantially better option in almost all cases.

I've seen enough of your threads to know how much money you've pissed into RC over the last few years. Pucker up and buy yourself ONE 3S battery to try. Just one. For now. Once you actually set up a vehicle for 3S, you'll start changing a lot more over. It's just so much better. Even if you're not into the ballistic speeds that volting up can give, the added control you get in a brushed crawler when you get a little bound up and need a smooth delivery of torque is well worth it.
 
I had that same stubborn mentality for a long time. Eventually I came around and decided to build a Slash with a 1/8 electronics to run on 3S. Since then, I've converted almost everything I have to 3S. It's a substantially better option in almost all cases.

I've seen enough of your threads to know how much money you've pissed into RC over the last few years. Pucker up and buy yourself ONE 3S battery to try. Just one. For now. Once you actually set up a vehicle for 3S, you'll start changing a lot more over. It's just so much better. Even if you're not into the ballistic speeds that volting up can give, the added control you get in a brushed crawler when you get a little bound up and need a smooth delivery of torque is well worth it.

Same boat.
Thought I had no reason to be getting into 3S, but bought a $16 1550 mAh 3S Ovonic pack off Amazon to put in the front tray of my TRX-4 and I will not be going back to 2S ever. Smooth low speed operation, and higher wheel speed for trailing? Yes please. And it's not like a pack rated under 2000 mAh is at all a detriment in a crawler - how many hours do you really want to be driving?

I only keep a small 2S around for when I drive my ancient SCX10 (until I switch out the Novak system for a HW 1080, and a crawlmaster sport 540).
 
Final note: I ordered a CrawlMaster 550 10T, so the problem is well on its way to being solved. With that, I'm going to stop posting in this thread.

Just so you are aware, your current gearing will probably overheat any 550 brushed motor in second gear, or at least eat up brushes quickly. Tall gearing is tall gearing, and going to a higher quality brushed motor will help some via higher efficiency, but we are still limited by brush size.

Volt up, gear down isnt my motto because I like how it sounds. It's so people get optimum performance without burning motors out.
 
Just so you are aware, your current gearing will probably overheat any 550 brushed motor in second gear, or at least eat up brushes quickly. Tall gearing is tall gearing, and going to a higher quality brushed motor will help some via higher efficiency, but we are still limited by brush size.

Volt up, gear down isnt my motto because I like how it sounds. It's so people get optimum performance without burning motors out.
Okay, well, I have to reply to a post from The Man Himself. :)

I agree that the gearing on my TRX-6 is too high for driving off-road in second gear, but that's not what I use second gear for. Second gear is for traversing flat ground quickly, so I don't have to listen to the high-pitched whine of a madly-spinning motor redlining itself in first gear. I downshift even to drive over a tall curb, to say nothing of sustained driving in rough terrain. (some people would find all that gearshifting to be tedious, but for some reason I don't.) The motor in my TRX-6 will spend most of its life running at a comfortable 25.7:1 gear ratio. My only crawler that sees sustained use in second gear is my Wraith, which doesn't have to work as hard driving on rough ground because it has much larger tires that roll over bumps more smoothly.

The TorqueMaster Pro 550 21T in my Wraith is still going strong several years later, by the way --- as are the custom-made 550 11T motors you built for my short-course trucks a couple years ago. "thumbsup" The secret seems to be Reedy Plutonium brushes; I concede I don't really understand why, but they get much less hot than copper brushes under the same heavy workloads.
 
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