MicroAce EMU kaput - help!

[scott]

Last night I tried using our MicroAce "Akagaeru" as a test vehicle on the layout, but it was running really strangely--it would zip along a full speed (fairly noisily), then stop dead. With a nudge, it would zip off again. It seemed like it might be a lubrication problem, the way it was "seizing up" even under power.

 

So I took it upstairs, took the shell off, and cleaned the gears out with a bit of alcohol, let it dry, and lubricated the gears in the trucks. It still didn't run smoothly.

 

Then I took off the inner cover so that I could see the motor and drive train, and added a bit of lubrication to the little u-joint-like pieces that connect the motor to the trucks. But once I put the cover back on, it didn't run at all! I tried pulling the cover back off to look for anything I might have messed up, but nothing was obviously wrong. So I put the cover back on, making sure that all the snaps were connected. Nothing--it doesn't respond to power at all in either direction.

 

What am I missing?

t

[CaptOblivious]

I don't know anything about MA motor cars, but I wonder if the motor had somehow come unseated? Making only incomplete electrical and mechanical contact? The noise might be the gears not meshing fully, and the intermittent behavior might be bad electrical contact.

 

I would take anyone else's advice here before you took mine, but this is what I would do first:

Take the shell off, and apply power directly to the pickup rails, bypassing the trucks. Does this work? You might need a roller stand, or some pretty long wires. If yes, then maybe it's the trucks?

If not, take the motor out and hook it up directly. Does this work? If so, then the problem is somewhere between the trucks and the motor.

 

It might also be that there is something binding, and that is causing the motor to stall. You can test for this by putting a ammeter (a multimeter set to measure current) between one of the throttle leads and one of the rails, and letting it run. If the current spikes when the train isn't moving, then it is a binding issue, stalling the motor, and not an electrical issue at all. In fact, I might do this first. In this case, you've just put it back together incorrectly, more than likely, but I would pull the motor and test it directly too.

[scott]

Thanks for all the leads....

 

In this case, you've just put it back together incorrectly, more than likely,

 

Very likely--in my case, I always assume operator error first. I just can't figure out what I could have left out or mis-attached. There's just the one cover, and I didn't pull out any other parts.

 

Oh, well. I'll give it another look tonight.

[scott]

The patient seems to be recovering. I finally realized that the piece of insulating tape (?) with cutouts for contacts, etc., that was stuck to the roof of the shell was moving around and blocking contact. Once I put it back on the chassis, with the motor leads through the appropriate holes in the tape, and put the chassis cover back on, it ran. At first it still hesitated some, but that seemed to lessen as I let it run around the test loop. I'll try it on the real layout tonight, but I'm hopeful that it'll run much better. Which means local service will be restored.  :)

 

I also decided to replace the to-scale but non-functional couplers with the included Rapidos. The one on the unpowered car was easy. But the coupler on the powered car was already missing--which wasn't a big deal, except that it took the extremely tiny attachment screw with it. Now I'm trying to figure out where I can find a screw that small so that I can attach the Rapido at that end (it looks a little odd with nothing in front of the truck.....).

[CaptOblivious]

Wow, was I right then? It really was an electrical contact issue?

 

As far as I know, those tiny little screws are hard to replace unless you know exactly what kind of screw it is—and few of us do. You might try something like this micro screw assortment from Micro-Mark:

http://www.micromark.com/MICRO-SCREW-ASSORTMENT-10-SIZES-100-EACH,8545.html

[scott]

Wow, was I right then? It really was an electrical contact issue?

 

Yup! But I'm not surprised you were right.

 

As far as I know, those tiny little screws are hard to replace unless you know exactly what kind of screw it is—and few of us do. You might try something like this micro screw assortment from Micro-Mark:

http://www.micromark.com/MICRO-SCREW-ASSORTMENT-10-SIZES-100-EACH,8545.html

 

I was afraid of that--just when you want things to be standardized, they aren't.

 

Thanks for the link--I'll check that out.

[cteno4]

Wow, was I right then? It really was an electrical contact issue?

 

As far as I know, those tiny little screws are hard to replace unless you know exactly what kind of screw it is—and few of us do. You might try something like this micro screw assortment from Micro-Mark:

http://www.micromark.com/MICRO-SCREW-ASSORTMENT-10-SIZES-100-EACH,8545.html

 

I have been tempted by this in the past. wish there were fewer in quantity and more in different sizes/types though. would be nice to have a set of backups to use for that one screw that goes poing and then you hear the tap tap tap on the floor (or worse no sound and you cant tell at all where it went!)

 

cheers,

 

jeff

[CaptOblivious]

Posted this to a related thread, maybe it's helpful here too:

 

Northwest Shortline (makers of The Chopper) have a rather large catalog of modelling screws!

 

http://www.nwsl.com/Brochure%20Pages/broch%20MetricHardware%20Tools.htm

 

You might try just calling them up, and having a chat.

[Martijn Meerts]

For tiny screws and the likes you could also visit a hobby store that specializes in RC cars/planes/helicopters. Pretty much all the known brands have tiny screws as spare parts.

[scott]

That's a thought--maybe I'll try the local shop before I call NWSL; it might be easier not to have to explain this on the phone.  :)

[scott]

Well, the hobby shop managed to find a "close enough" screw and get the coupler put on, so that was great.

 

Of course, while I was waiting, I tried to fix the @$#%!@# pantograph, and made it worse instead of better.... ::)

[cteno4]

LOL, guess rosanna rosanna danna gotcha!

 

at least there are a bunch of tomix and tomytec pantographs that you can replace it with that would probably be a very close match!

 

well at least its running now and can connect up to others!

 

cheers

 

jeff