Chris Richards 3 | 24/02/2015 22:04:53 |
68 forum posts 13 photos | Hello, I feel a bit unlucky, my Harrison lathe single phase motor (looks massive and appears to have a separate capacitor) has started making some kind of noise that can be described as electric arcing and continues once turned off. Also my Myford Super 7 motor that looks to be the original one appears to making a ticking sound. I removed the drive belt to confirm this noise continues. I'm poor at the moment so cant just replace the motors so unsure if I should continue using them and ignore for now or if anyone has suggestions to things similar they have experienced? Thanks, Chris |
stan pearson 1 | 24/02/2015 22:43:57 |
![]() 135 forum posts 2 photos | Hi Chris I have a Super 7 which I bought from Myford about 20yrs ago, the motor started making clicking noises and was told it was brush noise and not to worry. It ran for about another 5 or 6 years before it stopped working forward but would run backwards I fitted a new motor and it has started making the same noise, don't know about the Harrison, hope this helps Stan |
Jesse Hancock 1 | 25/02/2015 08:54:46 |
314 forum posts | Hi stan, sounds like it was brush ware/slop. One side of the brush longer than the other hence running in reverse the brush makes contact on the longer side of the brush and if that's the case it's time to change the brushes. If it was a brush less motor I have no answers. Chris: Old electric motors are generally larger than modern day types as today they are all machine wound. That is a human doesn't need to put his hands or arms through the stator to put the coils in. As for the ticking I'd check for drying bearings, where a ball may be tipping over the top of the race making a ticking sound. If the bearings are of a type like a head race on a bicycle it's possible one of the balls has been lost! If not it could be a bit of paper or something touching to rotor?? Finally it could be worn bearings in either case so check the stator(s) for shiny rub marks made by the rotor.
Edited By Jesse Hancock 1 on 25/02/2015 08:55:52 Edited By Jesse Hancock 1 on 25/02/2015 09:04:51 |
john fletcher 1 | 25/02/2015 09:16:20 |
893 forum posts | Normally neither Harrison or Myford lathes have motors fitted with brushes, so rule that idea out straight away. Both have induction motors. Some induction motors make a clicking sound as the slow down when you have just switched off,thats the centrifugal switch closing. Try unplugging the lathe completely from the electric supply and see if the sound is still there. Also tell use how the lathe is connected, such as a DEWHURST reversing switch. Ted |
David Jupp | 25/02/2015 09:17:42 |
978 forum posts 26 photos | I'd stop using the Harrison, isolate the power and get it looked at by someone with necessary expertise. Myford's usually have induction motors, so no brushes to make noise. |
Jesse Hancock 1 | 25/02/2015 12:31:36 |
314 forum posts | A sheepish hello again. I'm sorry about that guys I completely lost the plot and that we were discussing single phase motors, excuse me while I get my foot out of my mouth. Chris For sure if you have a sniff and it smells at all it's a sure sigh it's arching / shorting or burning out and needs attention. |
Chris Richards 3 | 25/02/2015 12:45:25 |
68 forum posts 13 photos | I may be best to set a day a side to strip and clean them. In use the clicking on the myford sounds worse than the Harrison's odd noise, it does have a fan shroud but I've removed this and cleaned any swarf already. There's no burning smells so could pretend I'm hard of hearing and didn't notice? Talking about switches I could try run them in reverse see what that does.
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Chris Richards 3 | 25/02/2015 12:58:09 |
68 forum posts 13 photos | Just tested the Harrison again, so the noise is like static discharge or little crackling noises. I may be wrong but if I turn the motor off via plug power it doesn't do it and so possibly only by using the switch it happens. |
Bob Youldon | 25/02/2015 17:50:39 |
183 forum posts 20 photos | Hello Chris, The Myford motor noise is in all probability from the centrifugal switch not throwing out fully, Switch off everything and give it a good blow out with an air line, they seem to accumulate a lot of fluff etc in there and when mixed with the inevitable oil it will form into a sticky mess not allowing the switch to release correctly. which in turn may lead to odd noises. As someone has mentioned previously, a bearing, if it is a race may be breaking up, but generally the motors are fitted with sleeve bearings and not apt to make odd noises. If all else fails, turn the radio up! As for the Harrison, I cannot comment except to advise an examination by an electric motor specialist. Regards, Bob Youldon |
Nigel McBurney 1 | 25/02/2015 20:02:48 |
![]() 1101 forum posts 3 photos | On your Myford,the motor may have ventilation slots,may pay to see if any swarf has got into the motor,I fitted n aluminium shield over my Myford motor to keep swarf out. I suggest stripping the motor and clean it out and providing the motor has a centrifugal switch check if it it working correctly, I think it bad practice to blow out a motor through the ventilation slots ,all to easy to blow the rubbish further into the motor and possibly into the bearings. |
Ian S C | 26/02/2015 08:51:39 |
![]() 7468 forum posts 230 photos | Sound like the centrifugal switch on the Harrison is not fully disengaging, does it get up to normal speed, get it sorted before the start winding burn out. Ian S C |
Chris Richards 3 | 29/10/2015 21:11:24 |
68 forum posts 13 photos | An update on this thread for anyone with similar noises from a brooks crompton motor on a Myford. I finally had the chance to strip it down to discover the plastic fan grub screw loose so it was free to do its own thing hence the clacking noise. Nice and easy fix for something that sounded terminal. |
Gordon A | 29/10/2015 22:33:21 |
157 forum posts 4 photos | I had a strange clicking sound on my Myford motor. Thought there may be some swarf inside. Partially stripped it and blew it out with airline, no sign of damage or things that shouldn't be there. Put it back together but still clicking. Tightened up the loose motor pulley........problem solved. Gordon. |
paul 1950 | 30/10/2015 08:37:41 |
143 forum posts 32 photos | cooling fan may be loose |
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