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orraloon
15th May 2013, 08:58 PM
Hi,
My lathe motor has lost its torque. It is a 1hp induction motor and today while roughing a small bowl blank anout 8'' dia it would stall while taking very modest cuts. I have done largish turnings up to about 16'' on this with no problems before.
The motor spins up ok, was not hot and the headstock bearings were not even warm. Not being an electrical expert I am asking for some advise. Motor is about 5 years old and estimated hours around 2,000.

Regards
John

issatree
15th May 2013, 09:09 PM
Hi John,
How is your belt for tightness, & what Lathe is being driven by it.
I had the same thing many yrs ago & I Applied for Insurance & I ended up with a new motor.

DJ’s Timber
15th May 2013, 09:14 PM
:whs: check your drive belt before doing anything else. A slack belt matches your symptoms.

orraloon
15th May 2013, 10:42 PM
As soon as I had posted the question I had a nagging instinct to check the belt. You guys have confirmed that feeling. Ill do that tomorrow and get back with the result.
Regards
John

chuck1
16th May 2013, 02:00 PM
my drill press did a similar thing the belts were ok and it turned out to be the capacitor was on the way out but there was sparks comming off the motor.
it would spin up to speed but soon as any load was put on it it would clagg out! it was a cheap fix thanks to my mate

orraloon
16th May 2013, 04:34 PM
It is a Leady lathe so the tension is by the weight of the motor. I guess that is why I did not think of the belt first off. It is one of those micro v belts and still looks in reasonable order. I locked in the index pin and was able to rotate the motor pulley by hand on the first step. I have scrubbed out the v grooves with metho and given the belt a wipe with soapy water to ckean off any gunk. Still some slip on the slow speed (small pulley on motor end) but a fair bit better than it was. Looks like I need a new belt sometime. I may as well look at bearings as the shaft has to come out for the belt change. Anyone done the bearings on a Leady and will I need pullers and a press.
Regards
John

robo hippy
16th May 2013, 05:10 PM
If it is a V belt, you can replace it with a link belt. They do have two sizes. They will stretch out quite a bit, and you just pull out a link or two, and stretch it back out over the wheel again. I have found needle nose pliers very handy in taking them apart and putting them back together again. They do outlast standard belts, and do seem to slip less.

robo hippy

BobL
16th May 2013, 05:28 PM
If it is a V belt, you can replace it with a link belt. They do have two sizes. They will stretch out quite a bit, and you just pull out a link or two, and stretch it back out over the wheel again. I have found needle nose pliers very handy in taking them apart and putting them back together again. They do outlast standard belts, and do seem to slip less.
robo hippy

Robo he says it's a micro V belt so assume it is one like this?
268132

robo hippy
16th May 2013, 05:43 PM
Okay, I have heard them called 'serpentine' belts, though not sure why. Looks like the spindle will have to be pulled. Oh well...... That type of belt is supposed to give the best pull because of all the surface area. On some of the newer lathes, the headstock spindle will unbolt for belt replacement and for replacing bearings. I know the Oneway and my Robust will do that.

robo hippy.

Christopha
16th May 2013, 07:04 PM
My Leady is about 20 years old and has had about 4 sets of bearings.... she has done LOTS of work and it is relatively simple to remove the spindle. Pull the cover plates off the bearings and gently tap out always remember no metal to metal impacts. Common sense and patience will see you right mate.

orraloon
16th May 2013, 08:25 PM
Thanks Christhopa that does not sound too painfull.
The micro v belt I mentioned is a rather small v belt about 8mm wide. I dont know if link belts come that small.
Regards
John

nalmo
19th May 2013, 03:22 AM
Replacement belts available from Rydell Industrial belting. The belt has a code number that determines the length, but you need to tell them the number of peaks (or valleys) - they cut them off a long cylinder.