16 replies to this topic

[Shanks]

Hi Everyone,
I've had two Acto-Pink motors for a while now one I recently skimmed & added new bushes during this I removed the resistor & promptly lost it No problem I thought I have another on my spare motor so off I trotted to my local Maplins to get one, showed it the assistant behind the technical desk who looked like he knew what he was doing, did a few calculations looked on the comp & said they dont stock any as its a weird value. The colours are as follows Yellow, Violet, Red, Black, Grey this works out as 472MOhms 0.05% and is Non-Standard. If Maplins dont stock it as its not standard any Ideas where I might be able to get some?

[bromvw]

Hi Everyone,
I've had two Acto-Pink motors for a while now one I recently skimmed & added new bushes during this I removed the resistor & promptly lost it No problem I thought I have another on my spare motor so off I trotted to my local Maplins to get one, showed it the assistant behind the technical desk who looked like he knew what he was doing, did a few calculations looked on the comp & said they dont stock any as its a weird value. The colours are as follows Yellow, Violet, Red, Black, Grey this works out as 472MOhms 0.05% and is Non-Standard. If Maplins dont stock it as its not standard any Ideas where I might be able to get some?

Give RS Conponents a go mate


http://uk.rs-online....CFQcRfAodBQllKg

[Jonny Retro]

Are you sure it's a resistor & not a colour coded 4700pF (4.7nF) capacitor?

[bromvw]

Are you sure it's a resistor & not a colour coded 4700pF (4.7nF) capacitor?

omg i did'nt think of that . why have a resistor on the motor in the first place ? Doh . Must be a capacitor .

[Shanks]

Thanks for the replies, I looks like a resistor to me this is a pic of madmatt13's Pink Acto-motor from the TC forum to let you get a better idea of what im on about.

The resistor is shown here above the timing marks.

[bromvw]

Thanks for the replies, I looks like a resistor to me this is a pic of madmatt13's Pink Acto-motor from the TC forum to let you get a better idea of what im on about.

The resistor is shown here above the timing marks.

it certainly looks like a resistor . I'd get one as close as possiable to the original rating . It should'nt cause any issues .

[fatboyslim]

Hi Everyone,
I've had two Acto-Pink motors for a while now one I recently skimmed & added new bushes during this I removed the resistor & promptly lost it No problem I thought I have another on my spare motor so off I trotted to my local Maplins to get one, showed it the assistant behind the technical desk who looked like he knew what he was doing, did a few calculations looked on the comp & said they dont stock any as its a weird value. The colours are as follows Yellow, Violet, Red, Black, Grey this works out as 472MOhms 0.05% and is Non-Standard. If Maplins dont stock it as its not standard any Ideas where I might be able to get some?

Hmmm I think somebody's got a bit confused
yellow,violet,red,black,grey is a 472Ohm .05%
472MOhm .05% would be yellow,violet,red,BLUE,grey,also to be honest a 472 MOhm resistor would be a bit on the large size
Main problem you have is a .05% tolerance resistor is non standard (i.e Not common)
You should very easily be able to get 470 Ohm 5% resistor which would be yellow,violet,brown,gold (4 bands instead of 5)
In fact if you want a couple of 470 Ohm 5% resistors drop me your details in a PM and I'll stick a couple in the post for you
What I cant understand is why the motor has a resistor fitted in the first place??

[Shanks]

Yeah dunno why the heck I put that M in there Thank you for the offer Fatboyslim but I was talking to an old buddy from school who said that a 470ohm would do but if I really wanted to get 472Ohms I could put a 470 + 2 in series is this correct? as Maplins stock both of these.

I also have no idea why there is a resistor on there but they are even shown on there in the boxart pictures I've seen they are also on the Technigold motors not sure on the value of those whether they are the same as the Acto or different.
Never thought to ask him if they are actually needed or not?

[Champ85]

Guys, putting a resistor on a motor will do nothing but waste energy as heat.
Ideally you want to use three 0.1uF capacitors. One goes between the + and -, one goes from - to motor can, and one goes from + to motor can.
The idea is to reduce or eliminate the voltage spikes that occur as the armature rotates and the brushes engage and disengage the commutator segments. All those little sparks you see create radio interference and possible loss of control. AM radio systems are particularly susceptible. The capacitors absorb some of these spikes and reduce the noise.

I have no idea what that component is actually on the motor in the picture, but if it is a resistor, it doesn't make sense. In rare cases sometimes capacitors are manufactured to look like resistors just like that picture, but it gets confusing so most companies do not make capacitors look like that. The bands indicate the value and tolerance of the capacitor, much like a resistor.
This might help: http://www.electroni...itor/cap_5.html

[Shanks]

I think I will just leave it without one if there is no good reason for it to be on there I only wanted to replace it, if it not being there affected the way the motor worked. Would be nice to know what it actually is be it resistor or capacitor? As I got them both when they came installed in cars from Ebay it would be nice to know if they come NIB with them attached.

[matman]

Motor search NIB .

http://www.tamiyaclu...sp?id=297&cat=1

As you can see resistor
http://www.tamiyaclu...010194013_2.jpg

Have a look at these above .

[Shanks]

Thank you kind sir Looks like they do come with them NIB but still no idea as to whether they are resistors or capacitors Unless there are any instructions that might tell me or a well in formed Tamiyaclub member who knows for certain?

Motor search NIB .

http://www.tamiyaclu...sp?id=297&cat=1

As you can see resistor
http://www.tamiyaclu...010194013_2.jpg

Have a look at these above .

[Live Steam Mad]

I don't have one one of these motors myself but did you know that you can buy inductors (chokes) (does the same thing as a coil if I remember right from Physics lessons) that look very much like resistors. There is usually a 4 color band code for inductors, but some inductors do have 5 color bands ;-

http://www.learnabou...inductors04.php

...the value would then be 27 micro Henrys (uH) (where's the mu symbol when you need it LOL). That would help suppress the massive sparking that you get off any 540 sized brushed motor when you are running at highest ESC voltage (duty cycle).

Maybe it's an inductor.

Cheers,

Alistair G.

[Shanks]

Hows this for customer service. I sent an email to Hobby Co Tamiya's UK distributors asking if they had any info/tech specs for the motors resistor/capacitor etc etc, I got a reply from a guy that works in customer service dept saying that he would contact Tamiya & ask for any info on the motor & if they were resistors or capacitors.
Unfortunately Tamiya could not offer any tech specs on the resistors or in fact if they were resistors or not .

However after a couple of days I get an email from the same guy at Hobby Co saying that Tamiya were sending 2 of the items to them which they would then forward onto myself if I would like them to but I would have to wait 3-4 weeks for them to arrive in the U.K. then clear customs .

The said items arrived recorded delivery Saturday morning.

Thank you Mr Tamiya & Thank you Chris & Sue at The Hobby Company Ltd.

[stu22]

I believe you're looking at the Shockley diode.

[Shanks]

Diodes are black with a silver band around one end right? These look to be resistors with the colour bands if you look at the picture of one further up the thread you can see it.

[WillyChang]

Factory would never put Schottkys on a motor for you, what if ppl use it on a reversing ESC?



in Technigold manual (pic source kudos to google) its labelled a "condenser" so its a inline capacitor

Hows this for customer service. ...
Thank you Mr Tamiya & Thank you Chris & Sue at The Hobby Company Ltd.

gee any more great service like that could make one feel real guilty about greymarket mailordering from asia...