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Posted by engineman1@aol.com on May 10, 2008, 11:20 pm
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> Motor quality varies a lot when the country of origin is China. Maybe your=
> motor was from Taiwan.
> Cheap/low quality motors is what China makes for import to the U.S. Their
> motors don't need to meet any agency approval levels for safety or quality=
> like most other motors manufactured globally. The same goes for their othe=
r
> electrical components.
> Generally, the motors have no thermal protection, and the wiring is not
> likely to be marked for any temperature rating.
>
> You definitely got your money's worth out of those electrical parts, but t=
he
> other gotcha about stuff from China is, that's it's very unlikely that
> repair parts will be available. I believe that most of the import
> distributors just disassemble whole machines to use for repair parts, to t=
ry
> to keep their customers happy.
> The trouble is, when a design change takes place, an omitted part becomes
> unobtainable (no 800 numbers to call in China, I guess).
>
> Quite a few of the more recent motors from China have failed within weeks =
or
> a couple of months from the time of purchase.
>
> I generally keep a few spare quality motors around that I've found at gara=
ge
> sales or flea markets for $5 to $10. After disassembling them for cleaning=
> and inspection, I'll test them and put them on a shelf for future use.
>
> You could probably retrofit another AC motor onto your sander if there is
> sufficient space. A fractional HP motor made by Dayton, Leeson, Century or=
> another domestic manufacturer would probably meet your requirements, if yo=
u
> know what speed the original motor was.
>
> General machine replacement motors won't require the delay relay that the
> original motor needed.
>
> For sanders, grinders and other metalworking machines it's always a good
> idea to use a sealed motor that will keep the (electrically conductive) du=
st
> and chips out.
> Totally enclosed fan cooled (TEFC) motors are ideal.
>
> There are solid-state replacement motor starting devices, for about $40 fo=
r
> small motors, IIRC, but I don't remember the name of the manufacturer that=
I
> was looking at about a year ago.
>
> I remember seeing some open-frame treadmill motors from Surplus Center, us=
ed
> to drive small lathes and drill presses. Those might be the type you have.=
>
> WB
> .........
> metalworking projectswww.kwagmire.com/metal_proj.html
>
>
>
>
>
> > Hi Bill,
>
> > Thanks for the reply.
>
> > The original motor was AC with a delay relay instead of start cap.
> > Therefore I cannot simply use a start cap as there is no centrifugal
> > switch in the motor. The AC motor runs fine, but I have to hand start it=
> > to give it direction.
>
> > I'd also challenge the "cheap" statement as this thing has done 1000s of=
> > hours work and had the switch-relay not fried I am sure it would do many=
> > more 1000s as the motor runs smooth, cool and quiet.
>
> > The Treadmill motor that SC had gazillions of came with it's own
> > controller. I assumed people that were familiar with the treadmill motor=
> > from SC would know what I am talking about. Sorry, I should have been mo=
re
> > specific.
>
> > The schematic in the drop box that I mentioned is for the GE controller.=
I
> > have both the GE controller and the GE DC treadmill motor. This motor ha=
s
> > a 5/8" shaft about 1-1/2" long and keyed 3/16" I think. It us rated at
> > 2hp, but given it's size and max current draw, I am guessing closer to
> > 3/4hp.
>
> > It is not a permanent magnet DC motor as it has windings.
>
> > Perhaps see my reply posts to William and Art as well.
>
> > Dave- Hide quoted text -
>
> - Show quoted text -
=46rom your description it sounds like the motors I have.
I'm using one on my 12" lathe and one on my drillpress.
Here is a schematic and some info.(first two.)
http://pictures.aol.com/galleries/engineman1?backState=3DprevPage%3D/ap/myAl=
bums.do%26state%3DalbumId%253D4776.1493.1191439539706.1
For your other motor you might try a magnetic starting relay from an
old (before 1994) GE washer.
Engineman
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>
> Thanks for the reply.
>
> The original motor was AC with a delay relay instead of start cap.
> Therefore I cannot simply use a start cap as there is no centrifugal
> switch in the motor. The AC motor runs fine, but I have to hand start it
> to give it direction.
>
> I'd also challenge the "cheap" statement as this thing has done 1000s of
> hours work and had the switch-relay not fried I am sure it would do many
> more 1000s as the motor runs smooth, cool and quiet.
>
> The Treadmill motor that SC had gazillions of came with it's own
> controller. I assumed people that were familiar with the treadmill motor
> from SC would know what I am talking about. Sorry, I should have been more
> specific.
>
> The schematic in the drop box that I mentioned is for the GE controller. I
> have both the GE controller and the GE DC treadmill motor. This motor has
> a 5/8" shaft about 1-1/2" long and keyed 3/16" I think. It us rated at
> 2hp, but given it's size and max current draw, I am guessing closer to
> 3/4hp.
>
> It is not a permanent magnet DC motor as it has windings.
>
> Perhaps see my reply posts to William and Art as well.
>
> Dave
>
>