Problem with rc unit

[Marxpek]

Did you clean all connectors with alcohol? the metal tabs seem not to bad, but there are some scratches.

Are all 4 pegs on the drag-connector perfectly aligned? on the picture is seems as if the top one is ls slightly off compared to the rest, but that can be the camera angle too

[rkkm]

pegs are perfectly aligned, which alcohol will be best? vodka spirytus or something else?

[Marxpek]

Denatured Alcohol, also known as cleaning alcohol, not drinkable, most of the time about 70% or stronger,  any cleaning supply store should have it, maybe you have some in a medical kit?

Some medical kits also contain cloth wipes with alcohol in them for disinfection, these come in little tear-open bags, if you have a medical kit, there is a chance you have this,

However, when cleaning fragile stuff like electrical components, alcohol is a good thing to have around, i have a small jar that costed me a few euro's.

When cleaning with alcohol: take a small piece of cloth or cue-tip, make that wet with alcohol and just lightly rub the surfaces you want to clean, let it dry out a bit (vaporizes within seconds but i always give it a bit longer)

[mocbuild101]

No need for any cleaning! because there is nothing wrong with it!

Let me explain how it works:

The metal contacts on the position sensor get connected by the metal fingers/pegs on the output gear, and the RC unit only knows what position it's in by what is connected. Therefor the output can move without the RC unit knowing - until it disconnects from one of the contacts - which can be right up to the edge of the contact, creating a misalignment of the output of up to 2-3 degrees. Also after power to the motor is cut, the motor keeps moving a small amount past the center (which is what the RC unit detects) - also creating a misalignment.

I can make another video of mine with a longer lever on it if you want , because I know that it isn't perfectly centered (you just can't see it).

Edited May 27, 2017 by mocbuild101

[Marxpek]

Yes i know how it works, but if there is some dirt between 2 tabs, grease or whatever could cause it to think its connected, giving the sensor a wrong output and it might "skip" the middle tab.

Not claiming this will surely fix the issue but since its opened and probably touched by greasy fingers and stuff, it is always a good idea to clean it up, just to be sure. I always clean electrical component when i open up stuff, chances are i'll never open it up again after and at least now i know its clean and no dirt and stuff can cause issues.

14 minutes ago, mocbuild101 said:

creating a misalignment of the output of up to 2-3 degrees.

This is an acceptable misalignment, i would say mine is similar, but the video @rkkm showed does have a lot than that i think.

[mocbuild101]

Just now, Marxpek said:

Yes i know how it works

I was explaining it to @rkkm not you .

[Marxpek]

@mocbuild101 don't you think rkkm's unit in the video has way more then 2-3 degrees off?

18 minutes ago, mocbuild101 said:

was explaining it to @rkkm not you .

Hihi sorry got a sucked in there ;D

[mocbuild101]

Just now, Marxpek said:

@mocbuild101 don't you think rkkm's unit in the video has way more then 2-3 degrees off?

Maybe slightly more, but it could be the camera angle.

[Marxpek]

23 minutes ago, mocbuild101 said:

Maybe slightly more, but it could be the camera angle.

Could be, i also had the feeling somewhere nothing is wrong here, but since @rkkm says it happened suddenly after a drive outside and the misalignment looks pretty big to me in that video, i can imagine there is an issue here.

IF there are some metal shavings and dirt/ grease between these tabs, the sensor might think it is in the middle while (because there is a bridge of metal or conductive material between 2 or more tabs) and it will not take action to re-positioning , because it thinks it is in the middle.

[mocbuild101]

48 minutes ago, Marxpek said:

but since @rkkm says it happened suddenly after a drive outside and the misalignment looks pretty big to me in that video, i can imagine there is an issue here.

That is a good point...

One other thing you could try @rkkm, is attaching the spring-loaded steering module that the RC unit was designed to work with (without anything else attached) and see whether it makes it more centered.

Also make sure all the parts of the RC unit are screwed together properly, and that the screws are tight.

[Marxpek]

22 minutes ago, mocbuild101 said:

attaching the spring-loaded steering module that the RC unit

@rkkm i also suggested this earlier on, it will probably fix the issue, but it should function without, the return to center hockey spring might be the other option, but it still does not explain the sudden change in the unit.

One more idea that i had: the white reducer gear, the one you took out for the test and was showed at the end of the very first video, does that have any play on its axle? any damage to the teeth? and i think in the housing, which holds it in place, there is a plastic cap that acts like a bearing, (could also be on the axle of the gear itself, i do not recall) does that have any play on it?

[rkkm]

no damage to the gears in inside, i know that vid dont show this as i see it, but compared to my friends rc unit, he's is almost always centred, sometimes maybe a bit to left or right ( 1-2 degree ) mine is never centred and always about 8 degree from centre... 

[Marxpek]

I'm running out of idea's... if after checking all this we suggested and if you are still sure there is a issue, all i can think of is a break in the circuit board or wiring after this, but I do not know if that can be repaired...

[mocbuild101]

What about making sure all the parts of the RC unit are screwed together properly, and that the screws are tight.

Also, have you checked if any parts of it are bent slightly?

[rkkm]

ok problem fixed, i just got new rc unit and selled old, new one is way better, still never centred but only a bit, now ill invest in sbrick and servo.

[mocbuild101]

2 minutes ago, rkkm said:

i just got new rc unit and selled old

How did you do that so quick???

[rkkm]

selled mine for 40 euro on polish allegro and bough new from my friend who's got 3 of them, for 30 euro :)

but for now ill focus on getting money for sbrick and servo, unfortunately i have selled mine servo 2 weeks ago but now a big waste, ill buy new with just a bit higher price :)