Wicked dumb motor question

[bobbin]

I have a Singer 31-15 with an official Singer motor (1/3hp).  It was my first industrial machine and I have had it for over 30 yrs. (I'm sentimental).  I haven't used it much since 2005 but hauled it out, cleaned it up, oiled it, and fired it up to do some zipper work.  I also have a 1 1/2" double fold binder for it, so dedicated binder? :) .  It whirred along this morning, then made a different sound.  I put some fabric under the needle and tentatively used the treadle... .  It sewed in REVERSE.  Mind you, this a drop feed machine with NO reverse capability.  (unless to use the knee lifter and pull the goods toward you gently). 

I know a lot about different machines and how they are/can be used.  But I know "jack" about the actual mechanics of a clutch motor (that's why there are mechanics!).  Can any of you explain what has happened inside the motor to effect such a change? (the head is 1929 and I have to believe the motor is about as old). 

[sofadoc]

Flip the foot pedal around...........move your chair around to the other side.

Now you got yourself a left-handed sewing machine. :D

[jojo]

Hmm.....sounds like there's some New England witchcraft going on there.

[bobbin]

I emailed my brother (Mr. Mechanic) about it.  There has to be a really simple answer.  The motor hasn't seized so there has to be something afoul between the motor and the pulley/belt.  Who am I kidding? I have no idea what caused it.  :)

So, it looks as though I'll convert the US Blindstitch or the Nakajima 380 to a servo and recycle one of those clutch motors to the Singer 31-15.  I should probably just junk it, but my father loaned me the money to buy it when I broke and then returned it to me when I'd paid him back in full.  So I have a sentimental attachment to that machine.  Isn't that silly?

[sofadoc]

So I have a sentimental attachment to that machine.  Isn't that silly?

Maybe, but I know an elderly upholsterer who has always sewed on a 31-15. And he lays down a mean stitch.

I think it would probably be an excellent dedicated machine.

[SteveA]

I have the same machine.  I don't think the motor is anywhere near as old as the machine.  Here's mine

[bobbin]

Mine looks a little more evolved, Steve, but not by much, lol. 

I have a TON of feet for it (many of which aren't compatible with a needle feed mechanism) and 3 different grades of feed/throat plates.  It's as "bare bones" as it gets, but it required me to really learn how to stitch efficiently and professionally and how to produce high end, couture finishing techniques (no overlock machine!) to turn out polished, professional work.  Most of what I now know I perfected on that machine while referring to books that were frequently next to me.   

I have wanted to refinish the wood bench for many years now.  Maybe this will get my "rear in gear". 

[SteveA]

I have a zipper foot, welt foot, and one regular foot I filed down to get really close when I need to. Yes I can handle those just fine but if it gets too complicated I'm DOA  :)

The store near me sells machines with computer programs that draw pictures.  Pretty soon you'll be able to work your machine from your phone. 

There is something about using the old machine that makes the sewing enjoyable for me - but I can understand folks who need to turn over work quickly need a machine with updated features. One thing I can tell you is I've had the machine for 8 years or more and nothing has ever gone wrong. They made them forever back than.  Let me know how you deal with that motor so if it happens to mine I'll have a heads up.

SA

[Mike]

dumb question , but did the motor start running in reverse?

[Grebo]

Sounds like it Mike. Polarity check ?

Suzi

[bobbin]

I told the husband about it last night and he mentioned polarity, too.  How would  the polarity be changed?

[baileyuph]

Is it the head or the motor?

You can determine that;  disconnect belt turn handwheel, if it doesn't run smooth --problem is in the head.

Then set head on bench and turn hand wheel to see where resistance is happening.  In quest focus on feed dog mechanism and shafts running side to side of head.

Do a good inspection.

If problem is in motor, with head out turn it on and see what happens........It will either burn up or turn normal or ?  At least this might get one in the ball park.  If one is interested and has the time, research a motor reverse polarity problem, the likely hood of such would probably be explained.

A clutch causing the problem.......doubtful because head would turn smooth and motor would run smooth, if it is the clutch, it would at least be known. 

I suspect something in the head came loose or broke.   Like I said, would be a place to start.

Doyle

[sofadoc]

Here's a guy that had a similar problem with his bandsaw motor:
http://www.eng-tips.com/viewthread.cfm?qid=338598

Don't suppose there is a visable switch on the motor, similar to the FWD/REV switch on a drill? It may have failed internally.

[bobbin]

It's the motor.  The head performs as expected when not connected to the motor.  It moves freely and there is no resistance or any strange metal on metal noises.  The motor turns on and does its usual wind up to full speed (although the pitch of the hum is different).  But instead of moving the machine's handwheel in the normal direction (counterclockwise) it powers it in a clockwise direction.  The plug on the machine is  not polarized (will go into an outlet or extension cord either way).  I had it plugged into an extension cord (heavy duty and polarized) and then tried plugging the machine directly into the wall outlet and rotating the plug 180 degrees but it didn't make any difference.

My brother just responded and he immediately suggested a change in polarity as the culprit.   

[Grebo]

May be some things broken off inside & coursed a short circuit. 
I don't do electrics, I just know it's one way to reverse a motor.  :)

Suzi