x

Motor woes

jamesshipp 24 November 2013

Hi All-

I'm having some new problems with my motor, wonder if anyone's ever encountered anything similar. I suspect that the trouble's originating with the specialized parts I had made to allow me to control vibrato speed with a volume-style pedal, but I wanted to make sure it's not the actual motor itself.

My motor is stopping on its own. Mostly when it's at slower speeds, it'll just stop, often, oddly, when I hit a big chord or there's some other big event. (Maybe this is random and I am noticing the times it happens... not sure.) The fans just stop turning, and then if I get them started with my finger, they'll start again, so clearly the motor's on, it's just not putting out enough power to turn the fans; it's meeting some resistance, and I can't tell if it's a lack of enough current or there's some problematic friction; the reason the latter seems unlikely is that it's happening on both of my (modified) vibraphones, and seems to be a new phenomenon in 16 years of dealing with one of them.

Anyone have a similar experience?

thanks-

JAmes

Comments

Vince H Sun, 11/24/2013 - 15:20

Electric motors have various amounts of start-up torque. It may be that the addition of your pedal changed the torque--that is, the torque was adequate as designed, but the reductions you've made are affecting it. Also, I have had this problem when the fan axles are not lubricated properly or are slightly bent, which impinges motion and increases the requisite start-up torque. A little nudge and they start up.

Obviously you have to experiment to determine the cause. Before checking for mechanical impingement, it makes sense to undo your electrical change and see if all works OK. That would indicate the problem is related to your modification.

You could get a motor with a more powerful initial torque, or a workaround would be to insert a physical limiter in your pedal so that you could not bring the pedal so far down that the motor slows too much.

Randy_Sutin Sat, 11/30/2013 - 19:14

If it is one of the older motor, there is a question to be asked...

Have you been oiling it? It will have oil nibs if it is one of the older Bodine motors.

The other advice given here is good. Start up torque is a big issue. Grime is a big issue, even inside the motor. If you are close to NJ, there is a place that fixed my old Bodine motor about a half a year ago. So far, so good. He opened it up and cleaned it.

Beyond the above, there are lots of things that can happen and it is really hard to find somebody who will work on a small electric motor any more. They just want to sell you a new one that is not as good.

Good luck. If you hit a wall, send me an email message and I will hook you up with the guy who helped me.

Steve Shapiro Sun, 11/24/2013 - 22:28

I just had a similar problem. The cause was that my resonator fans REALLY needed to be oiled. Of course the fans should turn very easily, you should be able to spin them freely. Too much resistance was making the motor stop, and it was a simple fix!
Steve

Vince H Sun, 12/01/2013 - 17:01

James has a good point--if you have an old Bodine, it is likely gunked up. I assumed you had the newer Oriental Motor.

If you want to, you can clean the Bodine yourself--I've done it with a very old one. You just want to do it on an old sheet on top of some cardboard. Reason being, you will encounter some easily-lost ball bearings. If you are at all concerned, take pictures while you disassemble so you have a photo of each step. After cleaning and re-greasing, you will find that the motor runs cooler and perhaps quieter.

If you have an Oriental Motor and have altered it to accept a pedal, I'd like to find out how you did that. I'd like to give it a try myself. (Pretty sure Musser has been using Oriental Motor for at least 20 years if not longer.)

The Oriental motor website has lots of info on their enormous variety of motors, including the start-up torque of each model.

Forums

x
⇡