Replace armature of a tekin motor
 

Hi everyone, first post here, however I read a lot this forum, and so before anything thank you for all the help

The armature and brushes of my tekin 35t motor recently died very bad. First it started by not mooving (needing push) then lost a lot of power. Result, brushes worn out and armature damaged, beyond repair for me, look:

<a href="http://s1337.photobucket.com/user/Jcacosta/media/IMAG0146_zps3f951d67.jpg.html" target="_blank"><img src="http://i1337.photobucket.com/albums/o676/Jcacosta/IMAG0146_zps3f951d67.jpg" border="0" alt=" photo IMAG0146_zps3f951d67.jpg"/></a>

<a href="http://s1337.photobucket.com/user/Jcacosta/media/IMAG0144_zps7e32c0b3.jpg.html" target="_blank"><img src="http://i1337.photobucket.com/albums/o676/Jcacosta/IMAG0144_zps7e32c0b3.jpg" border="0" alt=" photo IMAG0144_zps7e32c0b3.jpg"/></a>

Its a 13-14month old motor, seems fair since im runing 3 cell lipo for last 2 month+a lot of water, mud...

My question is, can I change only the armature for one like this one Holmes Hobbies LLC ? If this is possible, I think it would be better than a new motor since is custom made and hand wound. The can with bearings seems to be OK

Mi Rig: Axial scx10 KIT DINGO stock+, tekin fxr esc+35Tmotor, 3cell lipo, castle creations 10A bec, hitec waterproof hs-646wp for steering, axial dig transmission with a traxxas waterproof microservo. spur (23T) and pinnion (80T) had been changed, a bulldog winch, a flysky gt3c (8channel), apart from that, what comes with the kit. My desert Dingo can be seen in next pic.

<a href="http://s1337.photobucket.com/user/Jcacosta/media/tumblr_mgu6jtLkbx1s3gtndo1_12801_zpsfa38106c.jpg.h tml" target="_blank"><img src="http://i1337.photobucket.com/albums/o676/Jcacosta/tumblr_mgu6jtLkbx1s3gtndo1_12801_zpsfa38106c.jpg" border="0" alt=" photo tumblr_mgu6jtLkbx1s3gtndo1_12801_zpsfa38106c.jpg"/></a>

Re: Replace armature of a tekin motor
 

I would say that the commutator of your armature is damaged beyond repair.

Most 540 armatures, such as you've linked to, are interchangable with one another. Just measure your commutator diameter to make sure you pick the right one.

And yes, a handwound armature and some fresh brushes will make your motor essentially better than new, as long as you haven't overheated it to the point of the magnets loosing strength.

Seems to me like your gearing is a little high for 3 cell use, but I suppose if you mainly trail ride at a walking pace or faster you can get away with it. I personally tend to run my 35 turn machine wounds geared at between 12/87 and 14/87, but I mainly rockcrawl at a snails-pace over technical terrain with my SCX.

How long do you run you truck for at a time? I can run mine for almost two hours before the 5000mah packs dumps and still not overheat the motor.

Re: Replace armature of a tekin motor
 

Thanks for the answer,

well, I really like the speed and basically do trailing and occasional crawling during trailing. I used that motor with a 2 cells for like 1 year and 3s for like 2 month (1.5 hours per week). I prefer not to change the gearing, a stock 2 cell rtr axial rubicon with 27t is a tiny nit faster than my setup, obviously half the torque.

I have a 3 cell 6400 mah battery and it has never run out on 1.5 hours runs.

Never really checked the temperature. However after the motor died i put a silver can (tamiya 540 johnson of my tamiya m05), an old motor with a lot of races on. It was that or not using the RC since i had no more motors, anyway those silver cans are cheap. After a couple of minutes it was insanely hot, barelly using the accelerator. to the point of using water to cool (i was trailing in rocks in a river) So I guess I might be overgearing.

would it be insane to put a motor heat dissipator or with the speed of the rig it would useless?

anyway, what bothers me is what you told me about the magnets damaged, how can I know?

Perhaps maybe better to buy the can also from holmes.

Re: Replace armature of a tekin motor
 

Heat sink?
No I think any help is dissipating heat is good.
I have got the VP Motor plate & gear guard in my rig & all that aluminum helps pull heat from the motor & cool it.
http://i1123.photobucket.com/albums/...ps25c0da0f.jpg
If you can fit a heatsink on there it will help dissipate heat from the motor quicker than without one.

Re: Replace armature of a tekin motor
 

Very nice thank you, will that motorplate work with my axial+dig transmission?

REading other post, I think my rig is super overgeared, 23t/80T with 3cell and 35t motor. I think I fried the can also. Maybe a better idea to buy a new motor. Dont know if buying the tekin tought. But definitely 35T. Ill keep the 3 cell and change 23t pinion for the stock 20t or the spur. With the motorplate should be ok. I really like the speed and power, dont want to loose it even if it means having a fan inside.

Re: Replace armature of a tekin motor
 

is this insane for a crawler rig? theese kind of heatsink with fan.

540 motor heatsink | eBay

very cheap... only problem mud or water, but those kind of fans seems standart and easy to replace, and some look well protected and also, could use an additional channel to turnit on or off. the cc bec should be just fine running it.

what do you think?

Re: Replace armature of a tekin motor
 

If you want speed and power you be better off going sensored brushless instead of trying to over gear a brushed 35T motor.

A Tekin ROC412 3100 with 87/18 or 54/12 gearing would give you speed and your motor would last a lot longer.

Re: Replace armature of a tekin motor
 

Yeah your gearing is way higher than I can run my 35T w 3s
I am running 87T Spur & 14T Pinion.
Fans will be getting killed if you are mudding or in water.
I would gear down to a 5:1 - 6:1 ratio & you may need to volt up (4s or higher) to get the wheel speed you want without the heat issues.
A 16T pinion on my 35T on 3s cooked a new HH Arm in less than a pack & now the 14T pinion is just right.
Gearing & motor heat is a bit of trial & error as well as personal taste.
Nothing you do to make your rig better for you is insane.
Plenty of people were positive the earth was flat, til some nut came along & proved em wrong.
A fan wont draw hardly anything so yeah 1 10A BEC with 1 servo & a fan should be plenty.

Re: Replace armature of a tekin motor
 

A 35t on 3s should be more like 16/87 or so to start...

Later EddieO

I've been running my tekin 35t on 3s geared at 14/87 and it seems just right..motor is usually warm to the touch after running for quite a while

Re: Replace armature of a tekin motor
 

14/87 on 3s how is it compared to 20/87 stock on 2s with a 35T in therms of speed? the stock dingo with 35t and 2s was very slow.

According to your experience, even stock 20/87 is overgeared for a 3s and 35T. I wanted 3s for the axial to be faster, no more torque, had plenty with the 35t and 2s for my needs.

Brushless I think is not an option because of water will drive the sensors crazy right? And will imply an expensive modification.



Thank you all for the help

Re: Replace armature of a tekin motor
 

How about using a different motor? not 35T

I have a 6400 3 cell and 2x3300 2 cell.

What options do I have if I keep the tekin fxr. I think the fxr needs 35T or higher for 3cells. I want a good compromise between speed and torque. 35T with 2 cell and stock 20/87 was too slow.

23/80 with 35t 3cell was perfect, but I dont want to change motor every month do to overheating ;(

Or use a 550 can instead of 540? maybe a titan 21t 550 on 2 cell? or 3? should be motor safe, dont know esc.

Re: Replace armature of a tekin motor
 

You will need to go to a lower turn motor to get the kind of speed that you want without burning out motors. Also since you run in water, you will want a cheap motor since water is really bad for motors. Going with a lower turn motor at 3S means you are going to need to replace your ESC.

At 80/20 with a 35T motor using 3S your top speed is about 7.3 Mph. If you go with a 27T motor with 80/16 gearing with 3S your top speed will be about 7.8 Mph and your motor temps will be in the OK range.

I would buy a HH BRXL Waterproof ESC and HH Trailmaster Sport motor which is 27T. The Trailmaster Sport only costs $12 so it isn't a big loss if the water ruins it.

Here is the link to the calculator I used for the speed calculations.
R/C Calculations

Re: Replace armature of a tekin motor
 

Hi all,

Thank you!

I saw some post about people running fxr with titan 21t or some 27T on 3 cell, I think it will work with the HH trailmaster motor 27T since im not using esc bec (less heat)

In any case, what should be the gearing to avoid overheating, I guess something like 20/80 or 20/87? Because 20/87 is as low as I have (stock), I have a 23t pinion and a 80t Spur. HH recommends 5.5:1 mine is 4.35:1 aaaich

Thanks again

Re: Replace armature of a tekin motor
 

I think this would be a good point to start for a 27T as well.

87T s / 16T p = 5.437 : 1

I run mine at 87T s / 14T p = 6.214

So get yourself a 14T, 15T, & a 16T pinion & see which works best for you

Re: Replace armature of a tekin motor
 

I would start with 87/16 with 3S and check the motor temps after 5 minutes or so of running it to make sure you are not over heating the motor.

Re: Replace armature of a tekin motor
 

Ok thanks, will buy a 16T pinnion and see.

About the tekin fxr, will it burn on 3cell with 27T?

Re: Replace armature of a tekin motor
 

OK, for safe testing and operation, planing the same tekin 35T or equivalent and:

Buy 14-15-16-18T pinnio, i already have 20-23T and 80-87T spurs.
Buy a pen infrared thermomether.

For Insane mode activated (I will also do this). If I did overclocking to pc why not overgearing. this is what im going to do. Why not a heatsink with single or dual fan. Problem, that it fits. What do you think about this one:
http://i.ebayimg.com/t/NEW-Integy-Hi...RClQ~~60_3.JPG

Seems cool, problem, fan might hit the chassis. Option 2: more insane:

http://i.ebayimg.com/t/Integy-Twin-C...eWg~~60_12.JPG

2 fans, easy to moove the second fan, problem might hit the gearbox and part of heatsink should be outside motor.

The 2 fan has a protector for big stones, thats cool. Adittionally, I can put the fans in a free channel (I have 4 free) and turnit on/off whenever I want from control, this way if theres a lot of mud, better turnit off temporary.

Futur, could use the PSOC (+/-uprocesor) Im using for the lights to control fan speed with a temperature sensor.

Im really motivated What do you think?

Re: Replace armature of a tekin motor
 

Cool units, but none will allow you to overgear a motor. A CPU being overclocked is a much different scenario....

You need to gear your motor correctly and take care of it....

I think many times people need to realize these are crawlers (scale or not), not a race truck. They are not designed to go fast.

Later EddieO

Re: Replace armature of a tekin motor
 

Seems like a lot of trouble to make a go slow system go fast, just buy a good go fast system and be done with it. I love the speed to, I run the fxr and 35t on 3 cells also with a 15t piñon and 87 spur this works great for me but I'm into a slower scale mode then you like. Good luck with your choices and post up what you come up with. Btw, Eddieo is the man when it comes to advice and motors.