08-02-2014, 04:54 PM
Hi,
Thanks Big Al, perhaps if the belts cost a great deal anaesthetic will be included; I'm still awaiting belt samples and prices.
I've made a lot more progress removing more rust and old paint but it's taking time; each session I have on the lathe it improves that little bit more and I'm looking forward to the day when I can start painting but this is still some way off yet.
I knew this Lorch to be noisy from when I first heard it under power just before buying it but having tested most moving parts by hand I considered the noise would not prove anything too expensive to put right? A couple of days ago I removed both drive belts and sure enough the headstock appeared to be in very good condition with the mandrel and gears turning freely so this was a relief. Yesterday I pulled the lathe from the wall in order to gain full access to it; out of curiosity I plugged it in and powered it up now only running the bare motor; so this is where all the noise is coming from; this motor is the roughest running motor I've ever heard and I worked at Brook Motors for 24 years so have heard a few motors previously.
Yesterday afternoon I removed the motor which was very easy and took it to the bench. First job was to remove the two step flat belt drive pulley and this proved difficult. I've never come across a pulley of this type before; I thought it would be a simple case of slacken the grub screw/s and have at it with the pulley extractor but what are the four screw heads securing; these proved to be two long steel machine screws which came away without trouble but the other two were brass machine screws; one came away without fuss but the second refused to let go? There was also one heavy duty grub screw which I completely removed; I always remove such grub screws completely because many are sunk into the shaft so it pays to take them out to prevent binding and shaft damage.
I attached the pulley extractor and was pleased the pulley didn't put up too much of a fight but once the pulley was on the bench I could have a good look at it; what a strange pulley this is and why all the extra machining involved when it would have been considerably cheaper to cast a longer boss then bore right through? Anyway so far so good. With the pulley out of the way I could now start dismantling the motor to gain access to the bearings. Once again how strange; I've never ever seen a motor of this type; I wondered what the lever and very crude strip metal linkage was for? Now having gained access I could see that the lever is used to rotate the brush holders around the Commutator axis by about 15 degrees?
http://www.allaboutcircuits.com/vol_2/chpt_13/12.html
Intrigued by this I browsed the web for some information and above is one of the websites I viewed; this motor is not the original Lorch motor because it was supplied by City Electrical Co of London. I was considering doing a motor swap installing a 3 phase inverter rated motor powering through a VFD but having never seen this type of motor before I'm now planning to retain it as it is so unusual? I stripped the motor in minutes and removed the bearings from the rotor using a bearing puller after I had de-burred the shaft. The non drive end bearing ran freely with signs of wet lubricant but the drive end bearing was packed with solid gunge looking extremely rough and this is possibly the source of all the noise? The motor internal connection leads are suffering from aged and broken insulation so I'll sleeve these and I was surprised to see the brush holder plate rubbing against the leads like a knife so I'll sort this out too. With the bearings removed these were wiped clean then measured and identifications noted. Unusually both bearings were identical regarding size; the drive end bearing is usually larger than the non drive end bearing?
Bringing the bearing details up to the bungalow I set about browsing eBay for bearing replacements but couldn't find the code so worked from the dimensions and ordered two new bearings at just under £8 delivered so now I'm waiting for these to arrive. This motor has grabbed my interest and I'll be very interested to hear it run with new bearings installed; the new bearings chosen are fully metal shielded unlike the originals which were open. I've been removing rust and old paint from the motor ready for reassembly then I'll treat it to a decent paint job. I've also given the motor pulley a birthday; I started rubbing the pulley down by hand using abrasive paper on the bench but this was tedious so I cheated and turned a dummy wooden mandrel allowing the pulley to be mounted between centers on the Graduate woodturning lathe; this made the task much more pleasurable. If the motor behaves once rebuilt then I'll use it and not bother converting to 3 phase; if I do retain this motor I'll certainly change the linkage because the rusty strip steel linkage currently installed clashes with the lathes overall high quality.
Kind regards, Col.
Thanks Big Al, perhaps if the belts cost a great deal anaesthetic will be included; I'm still awaiting belt samples and prices.
I've made a lot more progress removing more rust and old paint but it's taking time; each session I have on the lathe it improves that little bit more and I'm looking forward to the day when I can start painting but this is still some way off yet.
I knew this Lorch to be noisy from when I first heard it under power just before buying it but having tested most moving parts by hand I considered the noise would not prove anything too expensive to put right? A couple of days ago I removed both drive belts and sure enough the headstock appeared to be in very good condition with the mandrel and gears turning freely so this was a relief. Yesterday I pulled the lathe from the wall in order to gain full access to it; out of curiosity I plugged it in and powered it up now only running the bare motor; so this is where all the noise is coming from; this motor is the roughest running motor I've ever heard and I worked at Brook Motors for 24 years so have heard a few motors previously.
Yesterday afternoon I removed the motor which was very easy and took it to the bench. First job was to remove the two step flat belt drive pulley and this proved difficult. I've never come across a pulley of this type before; I thought it would be a simple case of slacken the grub screw/s and have at it with the pulley extractor but what are the four screw heads securing; these proved to be two long steel machine screws which came away without trouble but the other two were brass machine screws; one came away without fuss but the second refused to let go? There was also one heavy duty grub screw which I completely removed; I always remove such grub screws completely because many are sunk into the shaft so it pays to take them out to prevent binding and shaft damage.
I attached the pulley extractor and was pleased the pulley didn't put up too much of a fight but once the pulley was on the bench I could have a good look at it; what a strange pulley this is and why all the extra machining involved when it would have been considerably cheaper to cast a longer boss then bore right through? Anyway so far so good. With the pulley out of the way I could now start dismantling the motor to gain access to the bearings. Once again how strange; I've never ever seen a motor of this type; I wondered what the lever and very crude strip metal linkage was for? Now having gained access I could see that the lever is used to rotate the brush holders around the Commutator axis by about 15 degrees?
http://www.allaboutcircuits.com/vol_2/chpt_13/12.html
Intrigued by this I browsed the web for some information and above is one of the websites I viewed; this motor is not the original Lorch motor because it was supplied by City Electrical Co of London. I was considering doing a motor swap installing a 3 phase inverter rated motor powering through a VFD but having never seen this type of motor before I'm now planning to retain it as it is so unusual? I stripped the motor in minutes and removed the bearings from the rotor using a bearing puller after I had de-burred the shaft. The non drive end bearing ran freely with signs of wet lubricant but the drive end bearing was packed with solid gunge looking extremely rough and this is possibly the source of all the noise? The motor internal connection leads are suffering from aged and broken insulation so I'll sleeve these and I was surprised to see the brush holder plate rubbing against the leads like a knife so I'll sort this out too. With the bearings removed these were wiped clean then measured and identifications noted. Unusually both bearings were identical regarding size; the drive end bearing is usually larger than the non drive end bearing?
Bringing the bearing details up to the bungalow I set about browsing eBay for bearing replacements but couldn't find the code so worked from the dimensions and ordered two new bearings at just under £8 delivered so now I'm waiting for these to arrive. This motor has grabbed my interest and I'll be very interested to hear it run with new bearings installed; the new bearings chosen are fully metal shielded unlike the originals which were open. I've been removing rust and old paint from the motor ready for reassembly then I'll treat it to a decent paint job. I've also given the motor pulley a birthday; I started rubbing the pulley down by hand using abrasive paper on the bench but this was tedious so I cheated and turned a dummy wooden mandrel allowing the pulley to be mounted between centers on the Graduate woodturning lathe; this made the task much more pleasurable. If the motor behaves once rebuilt then I'll use it and not bother converting to 3 phase; if I do retain this motor I'll certainly change the linkage because the rusty strip steel linkage currently installed clashes with the lathes overall high quality.
Kind regards, Col.
Happiness is a wreck of a cabinet to restore.
