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Spoon
2006.04.30, 11:32 AM
I know everyone is trying to make faster and faster motors but I think there is definitely a market for slower motors.

Reasons for wanting a slower motor.

1. You have some loaner Mini-Z's and you don't want people to trash them.
2. You have young kids that keep the throttle pinned when they run into a wall, frying the stock fets.

So, how would you make a "slow stock" mini-z motor? Something that wouldn't fry the fets if you had the throttle pinned for a couple of seconds while you were against the wall?

More turns,weaker magnets?

I don't know much about motors but I would like to hear from those that do...

arch2b
2006.04.30, 01:52 PM
i would love to have a dud or slow motor for brandon :rolleyes:

alos looking into spec motors for future dc series ;)

Draconious
2006.04.30, 02:17 PM
Do what some one did... modify the TX... with a plastic screw... so it cant go full throttle :)

Or maybe put a motor from a Mini-Z boat or epoch in it ? lol (would have to test amps first).

HammerZ
2006.04.30, 09:51 PM
I have toyed around with the idea of using resistors on both motor leads. Only if I can find the right value, and it would keep the level down low enough to not fry the fets.

It would be a good idea for loaners and rental cars, to keep them slow enough for new drivers to get a handle on.

sciencemike
2006.04.30, 11:51 PM
To make a slower motor you need to remember some motor basics. Magnets change the magnetic stator field, and relate torque to top speed. They have nothing to do with the stalled current flow. To decrease the stalled current flow you can either 1. Use larger gauge wire..(Smaller diameter wire has a higher resistance.) 2. Use more turns on the armature. Here you need to go into the no mans land aka >70 turns. Although in theory you should be getting more torque out of these motors, instead all you do is strangle the current yet maintain decent torque. I actually have a whole spool of really fine wire (40 gauge high temperature motor wire) that can't be used for performance motors, i could wind you a couple of arms with this wire for a reasonable price or trade for MR-02/MA-010 parts..

Email me... Also i know one of the best motor winders goes by Flashsp-2 on other forums(ill talk to him and see what he thinks). I know he is considered by many, including PH2t to be the best at performance motors.. But i dont think he has the right wire for your quest. So e mail me and ill send you out some to try and we will either slow them down or speed them up, depending on your likes.

bemoore
2006.05.01, 11:27 AM
I have toyed around with the idea of using resistors on both motor leads. Only if I can find the right value, and it would keep the level down low enough to not fry the fets.

It would be a good idea for loaners and rental cars, to keep them slow enough for new drivers to get a handle on.
This is the best suggestion so far. Added resistance would have the effect of reduced accelleration and top speed. And it's simple. Motors with special arms or magnets are not simple or cheap. Most of my experience is with slot cars, so I may be a bit off on the value, but I would start out with something like 5 ohms total resistance. One resistor in each lead or a resistor in only one lead. The main problem will be heat. The resistor(s) will probably get hot, so using two may be better. And they probably need to be able to handle at least one watt total.

imxlr8ed
2006.05.01, 01:03 PM
Best thing I found for loaners.... loosen the ball diffs. Set it to the point where it starts to whine a bit when the car starts out. It's not an absolute prevention measure, but it does definitely help to save the board !

Spoon
2006.05.01, 01:46 PM
Best thing I found for loaners.... loosen the ball diffs. Set it to the point where it starts to whine a bit when the car starts out. It's not an absolute prevention measure, but it does definitely help to save the board !

I thought about that when I was adjusting the diff on my AWD (I think that's what motivated the question) but I think that would change the handling of the car. That's probably not a big deal for loaner car speeds though.

The other thought is that loaner cars may not have ball diffs installed.

sciencemike
2006.05.01, 04:17 PM
I was thinking about it last night, you should try an xmod gen 1 motor. They are a buck from A T o M I C M O D S and they have a rumored 89 turns on them. Purchase the S1 motor. The stage 2 will have fewer turns and will make the car go faster.. Try the stage 1.

As for the resistors, you will have to use power resistors. They should be rated at at least 4.8v x .5 amps = 2.5 watts. One should suffice. But again if you dont want to deal with this and the xmod ones are still too fast then just contact one of us motor winders. we can get you a slow one for im sure less than 15 bucks. The great news is that the batteries will last for ever doing it this way... ;)

Flashsp-2
2006.05.21, 04:07 PM
Thanks for the kind words SciMike. As for the xmods gen1 motor, it is somewhere around 80-90t (I unwound one before). I don't recall exactly, but I know it took forever to unwrap it all. As for the resistors, that could also be a good idea. I think the one SciMike suggested would be about right for the job. And for the stuff I carry, I just don't know how to make a motor run that slowly. One thing is for sure, keep the cheap brushes in there. They create much less rpm. Also, switching to some neo mags will slow it down by about 4k rpms. I think the 40ga wire Mike suggested would probably be the best way to go, with some neos, you would definitely be creeping with that setup.

HammerZ
2006.05.21, 05:06 PM
I thought the resistor idea was workable. I would stick with the two with one on both leads, over than just running one.

faydoiinspire
2006.05.21, 10:23 PM
Why waste time building another motor..just tie a small rock to the chassis.

Just go with a stock motor, if you want it to go any slower..why not just buy an xmod ..[i have one for sale btw] :rolleyes:

sciencemike
2006.06.16, 12:42 AM
It seems that a new friend of mine, contacted me about making him a set of motors to run with kids. It turns out that its pretty easy to dial in the motors for him. We sat and wound a couple and we got them going pretty slow. Im sure the batteries will last for about an hour with the lower draw rate. We got them going about 8-10 mph. I showed him how to wind the arms and i think he'll be winding them to make them go 6-8 mph max. So if anyone in the future will be wanting slower motors i can definately do it. I can make them 6-8, or 8-10 or 10-12 mph. I think a reasonable price is about 15 bucks each shipped. Ill be able to start making them as soon as i get my wire back. BD, if you want post up a comment or a vid of the cars...

builthatch
2006.06.16, 01:00 AM
It seems that a new friend of mine, contacted me about making him a set of motors to run with kids. It turns out that its pretty easy to dial in the motors for him. We sat and wound a couple and we got them going pretty slow. Im sure the batteries will last for about an hour with the lower draw rate. We got them going about 8-10 mph. I showed him how to wind the arms and i think he'll be winding them to make them go 6-8 mph max. So if anyone in the future will be wanting slower motors i can definately do it. I can make them 6-8, or 8-10 or 10-12 mph. I think a reasonable price is about 15 bucks each shipped. Ill be able to start making them as soon as i get my wire back. BD, if you want post up a comment or a vid of the cars...

slower than the stock motor? man, i don't think i could ever buy a motor slower than the stock motor, even with a gun to my head on a pirates plank.

Spoon
2006.06.16, 09:29 AM
slower than the stock motor? man, i don't think i could ever buy a motor slower than the stock motor, even with a gun to my head on a pirates plank.

Of course the slow motor woulnd't be for any decent Z driver, but to a 6 year old the stock motor can be very fast. You have to remember a small child is not going ot have the throttle control that all of us have. :D

Spoon
2006.06.16, 09:51 AM
ScienceMike,

This is slightly off-topic but I have a question for you. I think you posted this in another thread but I need some info for a FAQ I Am puting together.

For a 2x1 2x2 and 2x3 FET stack what's the limit for the number of turns you can run? It doesn't have to be exact but ballpark numbers would be great.

sciencemike
2006.06.16, 03:50 PM
Spoon,

I wish the actual rules were that simple. You see there are two different types of armatures. Long and short. The long ones have more length wire per turn-aka longer circumfrence. So they can have fewer turns and still be fet safe. But one of the most important thing is the wire gauge. Wire resistance is dictated by two different things its length and its gauge. Small diameter wire -aka large gauge- has more resistance per foot than large wire. I know you know this. So therefore, the current that a motor draws is dependent upon the wire gauge. We are pretty safe because to get the number of wraps around a motor that we need to for Miniz's we need to use 27-30 AWG wire. But remember that for each 3 numbers you go up in gauge the wire gets twice as small, and therefore doubles its resistance. So there is no easy number to give here.

But i know that the stock 2x1 or 1x2 whatever way you write it..
MR-01, MR015, MR-02 45 turns.
MA-010 35 turns. They use the 3010 fets i have personnaly used a 35 T (small arm) motor and the fets get pretty warm, but wont fry. I have a hunch that if you pinned this combo against the wall with full throttle it would fry.
4562' 2x1 = 30 turns is pretty safe, although i have never run a 2x1 stack so im not absolute on this.

Now as we go to 2x2 fets we have multiple ways to do the fets if you do a stack of stock under 4562's or 2x4562's or there are IRF 7317 fets. So its hard to make rules again...

But i have routinely used 28 turn motors on the 2x2 fet stack. Although I have some super wire i wind with 26 gauge 220C that has really low resistance and it can warm up a 2x2 stack. But safely, i think that a 2x2 (4562's)can handle down to 24 turns of 28-30 gauge wire.

The reason that i like a 3x2 stack is that its difficult for NiMH batteries to push enough current to even blow them. For example i had a silver wire motor i wound with 24 gauge that was basically like shorting out the leads, it drew 10 amps unloaded, and the stack got really warm, i dont think it can easily blow, And this motor is way too hot for anyone to ever run in a z. Maybe xmods would run somthing like that, but for us its useless.

Spoon, i saw your fet post, i didnt comment on it because stuff happens, and i would hate to get some whiner who has a 45 turn motor and it frys a stock fet and then complains. You can be running a stock motor and it gets pretty hot, somthing comes loose or melts and the fets fry. I also dont know the exact limit fets fry in most cases, i just know it where i have fried them. But after you fry a 2x1 stack you dont often come back and retest a slightly less hot motor in a newly fetted car. At least i dont. I throw in a nelly or 2x2 stack and then i have insurance.. Im sure itll all change when i start running the OLPS, or drive in the stock classes, but for now i just use a fet stack or nelly as insurance against burning out my fets. Its dangerous to burn out fets. Sometimes they get hot enough to scoarch the fet pads, and thats a toasted board.

Although i know motor winding well and a decent bit about fets, the real person you need to consult is Ph2t. He knows more about this stuff than anyone. Kinda scary that guy's brain is actually.

michvin
2006.06.16, 04:12 PM
you can buy a speedy BB motor. 7 out of 10 will be slow :)
just kidding, i know it's not a solution to the problem :)

Spoon
2006.06.16, 04:30 PM
Thanks for all of the info Mike. At some point I am going to help administer the FAQ on the site and if I remember I would like to include this in one of the posts.

I was hoping to be able to put together some general guidelines for numbers of turns with certain FET stacks but as you pointed out it's going to be a little tougher than that. I didn't even consider different wire gauges.

If I ever go back and put a stack on a car maybe I'll go right to a 2x3. I think at this point my next step is AD band so I probably won't be doing any FET replacements any time soon.

I'll just leave out the recommendations in the article I am putting together. I'll probably post a draft soon and I would like you and some of the other motor gurus to take a look at it and make sure all of the information is correct. After that I'll post it on the FAQ or on mini-zracing.com.

Thanks again for the info and taking the time to post it.

Spoon

briankstan
2006.06.16, 05:06 PM
Im sure itll all change when i start running the OLPS...

Hope to see your times coming in soon. :D

sciencemike
2006.06.16, 05:48 PM
Thanks for all of the info Mike. At some point I am going to help administer the FAQ on the site and if I remember I would like to include this in one of the posts. . . .. I'll probably post a draft soon and I would like you and some of the other motor gurus to take a look at it and make sure all of the information is correct.

Thanks again for the info and taking the time to post it.

Spoon

You are welcome. Thank you for taking the time to post and compile a FAQ sheet. I would love to take a look at it.

@Briankstan, your races look soo much fun. Cant wait to jump in and see what i can do.

Back on topic, the motors we wound are with 40 AWG and have anywhere from 65-100 turns to be slower.

I was also messing with power resistors, One power resistor on the order of 1/4 of an ohm was enough to slow the motor down a bit. It needs to dissipate about 5 volts and 0.5 amps so about 3 watts will due the job just fine, but i never found one that did the job right.

Z_408
2006.10.03, 03:33 PM
You are welcome. Thank you for taking the time to post and compile a FAQ sheet. I would love to take a look at it.

@Briankstan, your races look soo much fun. Cant wait to jump in and see what i can do.

Back on topic, the motors we wound are with 40 AWG and have anywhere from 65-100 turns to be slower.

I was also messing with power resistors, One power resistor on the order of 1/4 of an ohm was enough to slow the motor down a bit. It needs to dissipate about 5 volts and 0.5 amps so about 3 watts will due the job just fine, but i never found one that did the job right.

Thanks to ScienceMike I have been able to wind almost 40 motors now. With 40 AWG wire and 130 winds around each arm the cars are running at about half speed. They have a run time of almost two hours. I found out that with this wire anything over 130 turns does not make any difference.

I have also put these motors in the MZM with the smallest pinon and that thing just crawls. Also now with them going slower, they have more torque which makes these motors great for rock crawling.

I will try and post a video tonight.

thanks again ScienceMike.

Draconious
2006.10.04, 11:57 AM
Could always try to make a custom motor pod to move the motor away from the spur gear, slap an Overland pinion on the motor, and try to work a way for the motor pod to hold a 3rd gear... gear the car down to a lower gear, would save battery life. This is how the overland is... but the tire diameter and gear ratio wind up makign the speed close to the racers...

talk to PN or Atomic see if they will produce a Reduction Motor pod.. as a new product :)

Or retro fit the OL motor pod on the racer :)

-Turbo-
2006.10.10, 11:20 PM
ScienceMike, do you think you could make me one or 2 of these motors? MAybe 80-100 turns or so? I would be using it for crawling in an xmod.

dean
2006.10.20, 06:50 PM
I would buy a few off you too if you decide to sell any. ..thx.

nivlacs3z
2006.10.20, 06:54 PM
Hey, if Science Mike doesn't not want to take the order then I'm can do somethign like that for yall. I use 34AWG on mine and a dot of CA to insure that everything will stay. How much slower then stock do yall want it to be? (If yall want then I could use 40AWG and not have any CA on the winds)

Heres a pic of 5 70T armatures that I did not to long ago.
http://i9.photobucket.com/albums/a84/nivlacs3z/Motors/70Trear.jpg

dean
2006.10.20, 07:20 PM
Nice job, very neatly wound.
What do you use them for.
I want to test some in various mini-z cars and trucks.
I want 1 of the 70T and 1 of anything else you feel like doctoring up.
Maybe 3 or 4 motors?
How much would you want , I can paypal you.

nivlacs3z
2006.10.21, 06:31 PM
Thx thx, YGM

Z_408
2006.10.21, 07:33 PM
Hey, if Science Mike doesn't not want to take the order then I'm can do somethign like that for yall. I use 34AWG on mine and a dot of CA to insure that everything will stay. How much slower then stock do yall want it to be? (If yall want then I could use 40AWG and not have any CA on the winds)

Heres a pic of 5 70T armatures that I did not to long ago.
http://i9.photobucket.com/albums/a84/nivlacs3z/Motors/70Trear.jpg

How slow would you say those 70 turn motors are? The ones I wound are 130 turns with 40 gauge wire. I would say they are about half speed. Very nicely wound. I use new commutators on mine which just get crimped.

nivlacs3z
2006.10.21, 11:56 PM
70T pattern wound is actually a bit faster then stock I think. I just wrap it around a few loops on the ends before I crimp it. CA was just something that I dotted on to insure that the winds wont come off. Would you happen to have a pic of that 130T?? heh sounds like a pain... bet its pretty though

racerxcali
2006.10.22, 12:04 AM
Hey whats up i have a awd and a rm-2 and a monster but the rm seems too spin out noy handle tight and it seems like somethings dragingwhen it turns and it turns wide and makes a drag noise whats up nebe on the 02-rm just boat some fets and a inside ant i dont want to wwaist it on the 02rm if the car handles like that the awd drifts great i love it andthe monster seems slow already uped the awd to a new atomic stock ok that a whol bunch o questions
:(

nivlacs3z
2006.10.22, 12:40 AM
err sorry but what was your question? (maybe you just accidently posted in the wrong thread...) Oh btw, people aren't very picky about grammar, but most want some periods here and there.

Z_408
2006.10.26, 02:47 PM
70T pattern wound is actually a bit faster then stock I think. I just wrap it around a few loops on the ends before I crimp it. CA was just something that I dotted on to insure that the winds wont come off. Would you happen to have a pic of that 130T?? heh sounds like a pain... bet its pretty though

Below is a picture of my 40 guage 130 turn motor. Sorry for the blurry pictures though, my camera is not the best. These are a pain to wind and if you lose count, you have to start over. These are about half of stock speed.


Let me know if anyone is interested in purchasing one.

thanks,
Z_408

Spoon
2006.10.26, 02:55 PM
I would be interested. Would they come as a complete motor or just the arm? I could either use them for demo cars or maybe build up my OL as a crawler...

HammerZ
2006.10.26, 03:24 PM
Let me know if anyone is interested in purchasing one.

thanks,
Z_408

You should come up with a deal with the shop here to sell those. I may want some arms alone for some spare 130 cans I have around. Be good to turn my nieces kid's loose with. I think all those two know is full throttle, and that's about it.

-Turbo-
2006.10.27, 11:58 PM
Below is a picture of my 40 guage 130 turn motor. Sorry for the blurry pictures though, my camera is not the best. These are a pain to wind and if you lose count, you have to start over. These are about half of stock speed.


Let me know if anyone is interested in purchasing one.

thanks,
Z_408

I would. How much torque do they have? I wuld be using it in my xmod, which is a crawler. Would I need toupgrade the fets if I do use this motor?

shuter
2006.10.30, 12:14 AM
Below is a picture of my 40 guage 130 turn motor. Sorry for the blurry pictures though, my camera is not the best. These are a pain to wind and if you lose count, you have to start over. These are about half of stock speed.


Let me know if anyone is interested in purchasing one.

thanks,
Z_408

RE: Losing count of windings.

When I was winding slot car motors years ago I used to Measure the wire length of favorite wire/turn combinations. Just unwind and measure the length of wire on any wind you expect to be repeating. I Drilled a hole in the floor to put the armature shaft in and measured out from that. I put a mark at the proper distance with the wire size next to it. No more counting.

I felt that it gave me a more repeatable motor winding since the wire length and current draw would be exactly the same from motor to motor even if my winding pattern was different. That was forty years ago and there was no information on winding motors available. It just seemed logical to me. With all the information available these days perhaps the concept has been discussed and discarded for some reason. Just sharing.

Z_408
2006.10.31, 05:16 PM
RE: Losing count of windings.

When I was winding slot car motors years ago I used to Measure the wire length of favorite wire/turn combinations. Just unwind and measure the length of wire on any wind you expect to be repeating. I Drilled a hole in the floor to put the armature shaft in and measured out from that. I put a mark at the proper distance with the wire size next to it. No more counting.

I felt that it gave me a more repeatable motor winding since the wire length and current draw would be exactly the same from motor to motor even if my winding pattern was different. That was forty years ago and there was no information on winding motors available. It just seemed logical to me. With all the information available these days perhaps the concept has been discussed and discarded for some reason. Just sharing.

I thought about a similar idea. The only problem is that since this wire is so thin, if I unwind the wire to measure it might kink. That is the problem with the larger guage wire.

That is a good idea though, I will give it a shot. Did you use one continuos wire for all three arms?

Z_408
2006.10.31, 05:17 PM
If anyone is interested in a slower motor please send me an email and I can give you all the details.

thanks,
Z_408

Binh@insidelineracing.com

shuter
2006.11.01, 08:31 PM
I thought about a similar idea. The only problem is that since this wire is so thin, if I unwind the wire to measure it might kink. That is the problem with the larger guage wire.

That is a good idea though, I will give it a shot. Did you use one continuos wire for all three arms?

The wire will stretch out pretty well after unwinding. Just measure it, wind an arm counting the winds, adjust length if necessary. Once you are comfortable with the length you will no longer need to count.

You could cut the wire but one continuous wire worked best for me.

nivlacs3z
2006.11.01, 08:56 PM
lol maybe this makes to much sense.... but shouldn't you just move on and use pattern winding? This isn't some sort of servo motor or anything... make it consistant like a real motor should be.

Z_408
2006.11.02, 02:45 PM
The wire will stretch out pretty well after unwinding. Just measure it, wind an arm counting the winds, adjust length if necessary. Once you are comfortable with the length you will no longer need to count.

You could cut the wire but one continuous wire worked best for me.

If you use one continous piece of wire how do you know when to more on to the next coil?

Z_408
2006.11.02, 02:46 PM
lol maybe this makes to much sense.... but shouldn't you just move on and use pattern winding? This isn't some sort of servo motor or anything... make it consistant like a real motor should be.


The pattern winding would work but not with wire this fine and for this large amount of turns, however I may be wrong.

shuter
2006.11.02, 04:41 PM
If you use one continous piece of wire how do you know when to more on to the next coil?

Put a kink in the wire at the measured length. It will be easy to see and feel when you get there.

SaiTam
2006.12.25, 12:06 PM
Just use a slipping ball diff to protect the motor; drivetrain and FETs

marc
2007.01.10, 10:21 PM
This may be a stupid question I don't know. That's why I'm asking. But to slow the car down, can't you just add a bigger gear? Wouldn't that reduce the car's overall speed by adding larger gear on the differential part?

arch2b
2007.01.10, 10:44 PM
that reduces the torque but increases the overall speed.

less teeth=torque
more teeth=higher top end

builthatch
2007.01.10, 10:52 PM
This may be a stupid question I don't know. That's why I'm asking. But to slow the car down, can't you just add a bigger gear? Wouldn't that reduce the car's overall speed by adding larger gear on the differential part?

right, like using a 10T pinion on the stock motor...

it would reduce the acceleration, however, depending on the track, if the kid stayed in it, he'd hit a pretty good speed...

i think things would heat up too because the motor would be slowly fighting to reach it's peak RPM in an inefficient area of the band

it's still hard for me to believe that the stock motor is too much for anyone, even a young kid...but i guess it is.

Spoon
2007.01.10, 11:58 PM
right, like using a 10T pinion on the stock motor...

it would reduce the acceleration, however, depending on the track, if the kid stayed in it, he'd hit a pretty good speed...

i think things would heat up too because the motor would be slowly fighting to reach it's peak RPM in an inefficient area of the band

it's still hard for me to believe that the stock motor is too much for anyone, even a young kid...but i guess it is.

Some kids don't understand how to modulate the throttle. Even with all of th video games out there...it's just mask mash mash. Most get it after a while but I have seen a fair amount of people try to just steer the car at full throttle. It doesn't quite work.

I guess my only problem with the loose diff is the noise it would make. Hard to suck new people in when the car whines like a donkey.

marc
2007.01.11, 10:29 AM
that reduces the torque but increases the overall speed.

less teeth=torque
more teeth=higher top end

Oh yea duh. I should've remembered that from transmission class!

SaiTam
2007.01.11, 01:38 PM
My FETted Mini with a 7T and a box stock motor hits 27km/h on the speed checker.

The car also accelerates like a rocket.

Don't throw away that stock motor.

Hood
2007.01.14, 11:21 AM
We found a combination that produces a very slow motor for a beginner. Our AZGT series last year allowed any 70T arm in any can. We had all been running the stock motors for HFAY and had not really played with anything else. I thought the best combo would be the 70T arm and a Neo Mag BallBearing Can. We tried the Atomic Ball Bearing Can with a custom wound 70T arm and a stock 70T arm, both had great torque, but the largest pinion we had was a 9 and it was way too slow on the topend with the Neo Mags. We couldn't keep up with the stock motors with this custom setup..

Goodluck.

HammerZ
2007.02.05, 12:17 PM
Let's just say that I have ten cars that I want to setup for a youth group. In the end how much is all the neo mags going to set me back and the BB cases, resistors are cheaper just need to figure out what value to get. That's stuff that has to be added to the cost of a stock motor. The high point here is the torque is good. I was also thinking of maybe something inside the transmitter (have a number of KT-5's already from different readysets) can be done, that's a subject for another thread in another section though.

arch2b
2007.02.05, 01:19 PM
any custom motos is going to be cost prohibitive. modifying an existing motor or transmitter is going to yeild much more cost effective results.

HammerZ
2007.02.05, 02:13 PM
Just what I thought. I opened up my KT-5 to look at it, with three wires (white, red, and black) at first I thought of a switch and resistor on the white wire. Maybe better with a variable resistor to keep things simple, the best part is with that idea you can dial the speed right where you want it to be. The idea is to keep in inside the case and use a small screwdriver through a tiny hole to set it.

chitchc2
2007.02.27, 02:24 PM
The cheapest way is so simple and easy a child could do it.
You can reduce the voltage by using dead batteries or even making a cheap bypass battery with a dowel rod and a copper wire.
I use 2 bypass batteries to "break in" new motors.

arch2b
2007.02.27, 04:10 PM
Just what I thought. I opened up my KT-5 to look at it, with three wires (white, red, and black) at first I thought of a switch and resistor on the white wire. Maybe better with a variable resistor to keep things simple, the best part is with that idea you can dial the speed right where you want it to be. The idea is to keep in inside the case and use a small screwdriver through a tiny hole to set it.
please let me know if you ever get this done as i would love to do this to my sons tx

HammerZ
2007.06.28, 01:33 PM
An easy way to make a slow motor, this is from some of my bench parts. Stock motor arm in an X speed case w/x speed magnets. This produces a motor that runs slow with alot of tourqe. I have run it in a 3004 fet car for over an hour on a set of batteries, a stock setup is about 40 minuites on the same batteries. At first I called it an X stock motor, I think a better name is a "dog" motor. Both of the runs was with a 6 tooth pinion on the motor. I built the motor some time ago, but now I ran it in a car to see what it can do. Better fets may make it faster. Just be sure to paint or mark the case so it don't get mixed up with the other motors.

On the TX idea I did have an electronics guy I wanted to help me with it, but that didn't pan out for me. He had to move away to another job.

BobT
2007.07.13, 12:16 PM
I was attempting to run a track rental service. After my first job it was obvious that the cars were way to fast for the average "never ran a real RC car before" type.

I removed one AAA cell and it was a little slower but the lighter car made it still too fast. It was blowing away my XMods. LOL! I then limited the throttle by putting a piece of fuel tubing behind the trigger held in place with tape. It worked to a piint but was still too fast for newbies.

Johnny Throttle, a now defunct track that rented Mini Zs, used a resistor to slow the cars down and they worked great. I will check with the guy who owned it and get his formula.

BobT
2007.07.27, 05:22 PM
OK, Bob responded back the other day. They used a nail cut down to the length of a AAA battery then wraped tape arount the shaft so it would stay in place. The one dummy cell lowered the voltage. This did not get mine slow enough so I added a piece of fuel tubing behind the trigger to limit its throw. These are inexpensive answers to the question and they work.

A bonus is the batteries last longer. Lower the voltage and you lower the amperage draw. Thus longer run times.