Featherweight Guy Explains Motors - Let's do some Science! HD 720p
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- Опубліковано 20 вер 2024
- Featherweight Guy explains how the electric motor on a Singer 221 works, complete with a simple science demonstration of an electromagnet. A second science demonstration shows how the same principles of magnetic attraction that convert electricity into rotating force in an electric motor can be reversed to generate electricity. He also debunks myths about supposed causes of sluggish motors and shows how to eliminate other possible causes before blaming the motor. He then shows where the most common problems originate in the motors and how to correct those problems. More info at: Featherweightguy.com
Excellent video. A follow up showing how to test an armature would be excellent. I know you like Bob Fowler but I don't think he has shown that using an ohm meter. Thanks for what you're doing for the vintage machine aficionados.
Just to be clear, Bill: I’ve got zero credentials in electrical engineering and don’t want to pretend I know in detail how to properly test everything. What I’ve learned is mostly from the School of Hard Knocks. The basic test of an armature is to go “around the commutator” and test each coil with an ohm meter by touching the probes to commutator bars opposite each other. As you go around, they should all read the same, or be very close. If not, it’s a bad armature and will need to be rewound or replaced.
I have an ohm meter but I didn’t know where to test. I have a 221 motor apart now and will check it out - I thought this might make a good video showing how you test a motor as I hadn’t seen anyone else do it - I hope you keep going as I love your meticulous approach
So glad that you made this video! I am trying to become a restorer…it is quite a path.
Welcome to a great pursuit, Kevin! Just keep at it. You might want to start with free/cheap machines and develop experience and confidence along the way, before you get into a more costly Featherweight. There are plenty of good old black Singers out there. Singer 66 and 99 models are great and sew really well. The 15’s are also excellent, though I like the top-load bobbins on the 66/99.
@@wfjenterprises--billjohnso8701 thank you
I have a mistake around the 8:00 mark. I stated they the taller slot in a household electric outlet is the hot circuit. I had it backwards. The tall slot is neutral and the shorter slot is hot. Thankfully, on the Singer sewing motors, it does not matter which field coil lead is wired from the hot circuit.
My apologies for the mistake, which Bob Fowler kindly brought to my attention.
Thank you for sharing a more in depth explanation of the motor. I have of question about the larger (11) bars that are on the armature. Do they need to be cleaned and polished like the commutator? I have a motor where those bars appear to be coated with the same varnish like coating as the copper wire that is adjacent to them. I really don’t know whether I should clean them or simply leave them alone.
You don’t need to clean them. Those are the steel core of the armature (like the nail in my demo). Remove anything loose or scaly but no need to polish.
@@wfjenterprises--billjohnso8701 Thanks! I’ll leave well enough alone. Next I need to master soldering new wiring. Hint, hint….
I highly recommend watching Bob Fowler’s videos. No need for me to repeat what he does so well.
Thanks for making motors so easy to understand. I have a 'smelly' motor. Is there anything i should be looking for that could cause it, aside from being burned out as you said?
Smelly is usually a bad sign, Robin. If you have an electric meter, you can use the ohms setting and test the resistance of each of the 11 coils in the armature, by putting your test probes on the commutator bars opposite each other. All 11 coils should show the same resistance. If they differ by more than a small amount, your armature is bad. I don’t think I’ve ever seen a motor with that burnt smell that turned out to be OK. My guess is that you’ll soon be shopping for an armature or another motor. Sorry to be pessimistic!
Thank you. I will try that. Hoping having my fingers crossed won't short circuit anything.