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  #1  
Old 10-26-2002, 08:42 PM
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aktiondan aktiondan is offline
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380 motor (again) it's all about gearing!

Well as some of you may know, I stuck a 380 motor in my Micro last month and was somewhat disappointed with the outcome. Running a 16T pinion and 8 cells, it was just about as fast as any Speed 300/Watt-Age 370/TOBB with a 14T running only 6 cells. Not all was lost however, my run times went up to over 1/2 hour and nothing on the car even got hot or warm.

At any rate, I thought that this motor had to be capable of more if I just could dial it in right. It's not always about "unloaded RPM" after all because yes, this motor has fewer rated rpm's than pretty much any other 280 motor out there. So without breaking my wallet, I popped on a 20T pinion I had laying around which brought the gear ratio down to 2.90:1. Which is very tall by most RC car standards which vary anywhere from 5 to 9:1. Unbelievably enough, this is where the 380 really shines. It's got so much torque that driving this gear ratio with the added weight of the car itself poses no problems. I went for a drive tonight with it and I have to say that this my fastest setup by far. The thing screams and still has plenty of torque to peel out on dry pavement. All I can say is, it is very fast. And the gear ratio is what did it.

Now this is what I propose if anyone wants to take the challenge. This motor needs more cells. My ESC can barely handle 8 yet I know that with 9 or 10 cells and maybe even a 21T or 22T pinion, it would absolutely SCREAM. I'd do it if I could, but not at the risk of frying my ESC. If you're getting bored with your Micro and want to try something insane yet totally feasible, then this is the setup to try out.

For more details, visit www.danmarx.org/micro/

Thanks for reading!

-Dan
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  #2  
Old 10-26-2002, 11:16 PM
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was that the setup that you used in your 65meg "crashtesthigh.mpg" or what?

judging by the straight speed (going down your street) my 7 cell powered great planes 280bb is about equal (14t pinion) if not the same speed. Your car does accelerate a crapload faster than mine though!

I am not afraid of the al-mighty dremal, I assume your website has the info on how to mount a 380 motor, so I'll go click my way thru, heh. If not, please post what parts were modiefied to make it fit!
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  #3  
Old 10-26-2002, 11:55 PM
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You exagerate when you say "65MB" file right? Cuz it's only 46MB. You didn't download that on 56K I hope??!! No, actually the setup in the crash video was eight 600mAh AAA cells and a Watt-Age 370. Which actually wasn't near as fast as the same motor with eight, 1100 mAh 2/3A cells. (Both running a 14T pinion). The motor just didn't last very long. Neither did my Speed 300 on 8 cells. But now I believe the fastest set-up to be 8+ cells and 20T+ pinion with this $7.50 motor. Dude, it's unreal. You gotta try it. And I just realized too that with such a huge pinion gear, you don't need to shave away the rear axle housing as much as I did. You may not need to shave it as all. You just need to mod the rear deck. But even that doesn't need to be modded if you're running a 150mm WB. Anyway, take a crack at it. I want to go 9 or 10 cells, but I think I'll stick with the 20T pinion. It seems to be a perfect balance between top end and torque.

-Dan
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  #4  
Old 10-27-2002, 12:02 AM
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yea sorry it was 45megs, I'm on DSL tho so it really doesn't matter, took like all of 5 minutes @ 80k/sec or so, I didn't watch it come in.

I'll try that if my current motor burns up anytime soon, but I just bought this great planes motor and it seems to run great, but my stupid esc is the same one you've got and I don't feel like pushing the limits on it. You say you run 8 cells on that futaba mc230? Thank goodness I have ~100 brick cells on my desk as I type this, so I can just make up a new pack for my micro, lol.

How long have you been running with 8 cells? I thought the mc230 could only take 7, so that's why I was running 7, which as you know is under the recommended power for the 280bb motor

I'll probably try your pinion mounting idea, but I already ground down, and notched the motor shaft so that I could get team orion alloy pinions to stay on the motor without flying off and losing the set screw after 10 laps...
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  #5  
Old 10-27-2002, 12:07 AM
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Dan,

Where did you get the copper tubing you used to fit the Big Pinions from?

I burned out the bearing on my 380 just recently, but I'm trying to restore it(marinade). I think the 14T caused it. So I've been wanting to install 20T-26T pinions on this motor, but couldn't find a tube strong enough to shove onto the shaft.

My 8 cell pack is in the works. Once I purchase a Race 20....I may try 9 or 10 cells. <---This will have to be recorded on video because I'll only do this a couple times, just to showoff at my LHS.

One guy at my LHS has his Speed 400 on a 26T, but he doesn't have the proper pack for this application.

-Ryan
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  #6  
Old 10-27-2002, 12:45 AM
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I have been running 8 cells on the MC230CR for months now. No problems. Except that the throttle trim is slightly skewed towards reverse so on a full charge the car tends to creep backwards when idle. Once the juice drops a couple of 100mV it stops doing it. Doesn't affect driving performance in any way though. Sometimes when you let off the throttle though, it'll slam on the brakes instead of coasting to a stop cuz it thinks your trying to hit reverse, which as you know the first time you hit reverse it just brakes. Kinda weird little glitch in that it's operating at a higher voltage than it's intended. But the ESC never gets hot or shuts down. Even with more cells these motors only pull like 5 amps. I think you should bump up the juice! That motor can certainly handle it.

So the copper tube I got at my LHS. They should have lots of in the airplane section. I'll attach a pic of what I got. 1/8" fits inside the standard pinion and outside the shaft of the 380. But this won't work for the 300/370/280 motors cuz the shaft diameter is smaller. Standard Micro pinions are designed to fit on these motors (well with some grinding). But the inside diameter of this tubing isn't small enough to fit tightly on any of those motors. Unless you used maybe another piece of smaller tubing inside the other tubing. But you're on your own if you want to try that. I think a 14T for your basic 280 sized motors is as big as you should go.

But 380 (and 480 I suppose) sized motors need bigger pinions, but not too big! I think around 20 may be good. Because remember when I tried the 30T using the 540 motor the thing didn't move at all. It just sat on the ground and hummed. So I'd stay away from anything even close to 30T. Maybe a 22T max for this 380. But once again, there's dimishing returns with everything. There exists an optimum gear ratio and battery number, the trick is just to find it. And unfortunately the only way to do that is by experimenting with it, testing it out, and observing the results. Isn't that what makes this hobby so fun though?

-Dan
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  #7  
Old 10-27-2002, 03:34 AM
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off topic, but your website says you have a finepix 2600 digi-cam. I've got a finepix 2300 (2.1megapixal) digi-cam which has a 64meg compact flash memory card in it, and even when I take the pics at high quality (1280x1024x32bit) close up shots get all blurry. What settings do you have on you camera? The model #'s are so close that there can't be that much of a difference in them right?
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  #8  
Old 10-27-2002, 06:48 AM
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Click!

BLiND,

Have you tried using the Macro function on the camera?
It's the setting with a little flower, used for close-up pictures.
On Some digital cameras you have to be at a minimum distance of 30cm (12 inches) from an object or it will not auto focus.
Check your users manual for the minimum distance.
Keep the recommended minimum distance and use the normal/digital zoom to concentrate on the area you want to caputure. Allow it to auto focus and then *click*
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  #9  
Old 10-27-2002, 09:30 AM
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Miha Holc Miha Holc is offline
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400 race 4.8V

I just quickly went through this discussion. Has anyone tried 400 race 4.8 V motor from Graupner.

This motor turns 4492 rpm/V pretty close to speed 300 motor @ 4833 rpm/V. Normal speed 400 (380) turns 2672 rpm/V.

I use both 4.8 V and 6 V 400 motors in boats. 6 V motor has more torque, but if you let 4.8 V scream with very good setup (almost flight), it is really fast. Both motors on 7 cells , 6 V on 500 AR and 4.8 V on 700AR, runtimes 4 minutes. But I think 8 500 AR should be a really hot setup in micro for short speed runs!
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  #10  
Old 10-27-2002, 10:52 AM
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aktiondan aktiondan is offline
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BLiND, do what Mondo says and use the Macro function. The effective focal length is like 3-6 inches. Pictures should be crystal clear within that range.

If I can refer you guys back to this infamous page http://www.hobby-lobby.com/speed280.htm you can see which motors have more RPM's but you can also tell which motors have more torque by looking at the Watts Out spec. I think that the most powerful motor on there would be the Speed 480 Race 7.2V motor with a whopping 67 watts and 18.7K loaded RMP. Which actually is the next fastest motor compared to the Speed 300, which we all know is pretty dang fast. But with a 22T pinion it wil make for a faster Micro than a 300 running a 14T. And the can is only 1.6mm bigger than the 380.

But anyway, before we go off trying to put a 480 motor (like that guy on ebay did, whatever happened to it?) I think we need to crack the 380 motor thing. There have got to be plenty of other 380 sized motors that have better specs than this Watt-Age $7.50. I couldn't even tell you what the RPM's or Watts Out on this thing are. I figure they may be similar to a Speed 400 which is pushing only 12K RPM's loaded and it's unloaded RPM is 2/3rds what a tiny Speed 300 is. If someone can find a 380 motor with around 30K RPMs and 70 watts, I think we'd have a good candidate to beat out a brushless system.

Honestly I think a 380 motor is totally practical for a Micro. It's still very small, but has so much more potential as far as options for gear ratios and number of cells. We're talking about being able to run anwhere from 6-10 cells and run anything from 16T-24T pinions which amount to almost an infinite number of unique performance combinations. I mean it's perfect really. I realize it's not for everybody. A buddy of mine still has his stock 180 motor in his Micro and he loves it. Says he doesn't need any more speed. That and he races it on weekends and everyone else runs stock.

Here's a cool pic of the Motor Fury: from left to right, stock 180, 370 (280 sized), 380, 540.
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  #11  
Old 10-27-2002, 11:00 AM
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Miha Holc Miha Holc is offline
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Quote:
Originally posted by aktiondan
If someone can find a 380 motor with around 30K RPMs and 70 watts, I think we'd have a good candidate to beat out a brushless system.
That's exacly speed 400 4.8V race! Or there is also Rocket 400 which is said to be little "tamer" but of course little more torque.

GR3320 SPEED 400 4.8V Race $ 13.75
HLH780 Rocket 400 4.8-6V $ 9.50

Forget 480 motors, waste of space, weight and electricity in a micro.

Last edited by Miha Holc; 10-27-2002 at 12:01 PM.
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  #12  
Old 10-27-2002, 12:01 PM
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aktiondan aktiondan is offline
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The Speed 400 4.8V Race looks promising, but I can't get over the 4.8V part. I imagine the motor would be burnt toast if you tried running 9.6V volts to it. It does pull 17 amps though, higher than any motor in that list. I had a Watt-Age Super 400 motor that I tried once. It was pretty fast, but I had the 16T pinion on there and I didn't realize then that I needed to go higher. I was messing around with it last week, running a few batteries to it, watching it spin, when a small screw or something fell inside the casing and lodged itself against the armature and the magnets. That motor will never spin again. But I bet it is similar to that Rocket 400. Which might be better than this Watt-Age 380 for gearboxes. Same price almost, couldn't hurt to try both.

I was driving my car around this morning. I think a 20T is almost perfect. You might could go 1 or 2 teeth higher, but I think that we're nearing the top-end vs torque on this motor anyhow. The motor actually gets hot now while running and my batteries are dying faster. Surprise surprise. I'm having some issues with it right now though. I think that brushes may be wearing out because it's starting to get way glitchy, running on it's own most times, steering into stuff and stopping and going at will. But man it's fast. The tires totally "balloon" when I run it in my hand. It's cool.

-Dan
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Old 10-27-2002, 12:52 PM
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380 motors

aktiondan,

Let us know the outcome of your experiments.
I am curious as to how you fit the bigger motors in the Micro.
This is regarding the actual motor mount configuration.
As I haven't got my paws on a 380 motor yet, I ask this: will the BB300 type motor mount hold a 380 motor?
(Talking of 380 size motors, the last time I owned one was when I bought my Tamiya Grasshopper many, many eons ago, anyway it was quickly replaced with a 540)
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  #14  
Old 10-27-2002, 01:05 PM
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[Edited by The Thunderer]

Last edited by The Thunderer; 10-31-2002 at 11:59 AM.
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  #15  
Old 10-27-2002, 01:13 PM
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RyMicroRS4 RyMicroRS4 is offline
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Thumbs up

Your motor stack look similar to mine except I have the followig motors:

TO Big Block
WattAge 370(300, Big Block,chubby)
Peak Turbo coreless(elite mod)(critical condition)
WattAge 380
Super 400,
GP 280BB
GPM Type R(R.I.P.)
Elite Stock(critical condition)
HPI stock(R.I.P.)
HPI Mod 45T
WattAge 380( #2...in the mail)
Speed 280 Race 6V(in the mail)

My list is pretty short..don't you think?!

Thanks Dan for the tip....I'm going to search my LHS for that copper wire and buy a couple pinions(20-23T).

-Ryan
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