Rango - Build diary

[Ellis]

Hey Nick, I've never used it! That video was the first test session. Otherwise straight out of the box. It was turning to begin with, just very slowly and thus barely audibly, but it was. I have now taken the soft start off, and it starts on demand now, but it is still completely lacking in torque and I'd guess barely touches 5k rpm. Should be going on 30k.

Will look at the wires, but again it's a brand new motor. Also, have tested for a short, there doesn't appear to be one. I can't see any physical or electric evidence of a fault. Very odd. Also a pain in the derriere.

[overkill]

OK, not working straight out of the box is bad! Are you likely to get another one in time, or is the align motor getting another run?

[Ellis]

I wouldn't be able to get another one in time sent to here (Spain). Would have to order one in the UK and install it there. But since there is no apparent reason for this motor to not work, am I not asking for trouble by ordering another one the same? And if it's indeed a compatibility issue then who knows what is guaranteed to work.

Guilherme is being a hero and is going to post me his spare weapon motor. It's a perfectly viable bit of kit, buckets of power for my small drum. If he needs it back I spose the poor old wonky-shaft Align is going to have to have a go for its fourth owner!

[Mouldy]

What 4 resistance readings did you get between phases?

[overkill]

Do you know if the motor is a delta wind or a Y wind - that will help diagnose the resistance readings. The resistance of a good winding is probably under 1 ohm and in a delta wind motor (the more common type of wind), you would probably still see a low resistance across an open circuit phase. If there is a short in the winding, it might be hard to tell without a specialised meter.

[Ellis]

Don't know enough about motor technologies to know what kind of wind it is. It's this model: http://www.hobbyking.com/hobbyking/s...90mm_EDF_.html


Resistance on our basic meter is about 1ohm for all.

[overkill]

Hobbyking mentions a "1.5V" wind on that page, so the motor is more likely to be a Y rather than a delta wind. If the resistance on all phases of a Y wind motor are similar, it can't be an open phase. My best guess is that one phase is shorted part way thru, which explains the heating and partial spin-up. Unfortunately, its probably not something you can fix.

I notice that the motor ends are fairly open - can you see if some of the wires are a darker colour then the others? If one phase is getting hot, the lacquer may have darkened as the wires heated up. At least you would know which phase was the issue then.

[Max]

Have you measured the resistance between 2 of the 3 wires in the3 different combinations ie. between first and second, between second and third and between first and third wires? I think they should all be the same.
Also, silly thing but have you checked the gold bullet connectors are soldered properly, I remover seeing a video where somehow a guy did one which didn't work properly and had similar problems to you.
Have you heard of anyone else using the same motor esc combination?

[Ellis]

I was just looking in each end of the motor, wasn't looking for discolouration, but I didn't register any, nor have I over the course of the day. I can look carefully tomorrow in proper light.

Also, yes, we have measured the resistance across the combinations, all the same. You make a good point about the connectors, if one were dodgy I'd expect the symptoms to change as we have handled the motor/wires a lot all day, but I will also check those off tomorrow.

Thanks again everyone for all the input, hugely appreciated. Had people on here, Facebook, Skype, and from Hobbyking trying to sort this for us for the past 8 hours. Yay, internet!

[Max]

Hi,
Just wondering which model lathe you bought and what you thought of it?