New Lathe problem

What would make my lathe to become slow to get up to speed? It was working fine and then just started to start slowly. Its starting at the same speen in forward or reverve. The motor is a double capacitor 240V. Any ideas? Thanks

Reply to
stu
Loading thread data ...

If the lathe is belt drive, slip off the belts and turn the lathe by hand. If its stiff you may just have a tight bearing somewhere. If its free, run up the motor with the belts off, if its still slow it could be a capacitor going down, or the centrifugal contacts being stuck open all the time keeping the start capacitor out of circuit. No smell of magic smoke or hot amps? Does the motor turn over easily by hand? as you see it could be a number of things Im sure youll find it. Ted Dorset UK.

Reply to
Ted Frater

The leather belt on mine shrinks from low winter humidity and lengthens this time of year.

jsw

Reply to
Jim Wilkins

It turns by hand just fine

I'll try this in the morning. I wasn't sure the there would centrifugal contacts in there.

No magic smoke as yet. Nothing getting hot that I can find.

Yes

Thanks

Reply to
stu

Where if any centrifugal switch might be will depend on the motor age, design, maker etc.

Generally tho there a set of spring return weights on the armature shaft. Ive had them work fine on motors 40 yrsold , and be seized up on a 5 yr old one. Generally under the end cover non output shaft.sometimes you can seethem on motors that have removeable inspection plates, on motors from the 1930's to 60's. Later motors tend to be more enclosed and difficult to work on. keep us posted what you eventually find it is.. Good luck. ted.

Reply to
Ted Frater

Usually you can hear an audible click on spin-down when the centrifugal switch resets. A bit late now for that maybe, but you might possibly remember hearing/noticing that after my mentioning it. It could still be clicking too, but not really making any sort of electrical connection.

Reply to
Leon Fisk

One of the capacitors has died. Double suggest cap-start cap-run, and it is the start cap which is most likely to have died.

Good Luck, DoN.

Reply to
DoN. Nichols

Thanks for the replies. The good news is the lathe is fixed. The supplier came up with a new motor. Seems to have been a batch. The better news is I get to keep the old one, so I'll still be trying to fix it.

I've have it open and the switch looks fine. So its most likely a bad cap or bad soldering. If I get it going it will go on the huge old pillar drill I have.

Reply to
stu

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.