On May 10, 7:46�pm, "Wild_Bill" wrote:
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 other
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 the
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 try
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 garage
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 you
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) dust
and chips out.
Totally enclosed fan cooled (TEFC) motors are ideal.
There are solid-state replacement motor starting devices, for about $40 for
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, used
to drive small lathes and drill presses. Those might be the type you have.
WB
.........
metalworking projectswww.kwagmire.com/metal_proj.html
"Dave" wrote in message
...
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 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- Hide quoted text -
- Show quoted text -
From 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/en...143 9539706.1
For your other motor you might try a magnetic starting relay from an
old (before 1994) GE washer.
Engineman