Another Denford Bowl lathe hopefully back from the dead!

[Fitzroy]

Wondering if thats not what I've already got in that photo I posted with the wiring niche. The one with the lettered wheel.
If all else fails might have to go down the replacement motor route as you suggested. I just a bit of a stickler with keeping things original...
Cheers

The wiring niche may well have an NVR incorporated into it as you have a coil at the bottom which could well be holding a switch closed once it has received power from the start button. However, your wiring niche is not related to swapping the motor from star to delta, that would be done on the motor itself, you may already know this! Do you have a photo of where the wires from A/B/C connect to the motor, is there a terminal housing on the motor? I have seen motors labelled single voltage on the motor plate still have delta/star configuration inside the terminal housing.

 

[grahame]

Hi grahame So your machine didn't have VFD and was running old school on original wiring? Was it single PH?

If you look at my original pics you will see the motor fitted - 3PH - and wiring - non original with added lock and panic switches plus the added wiring for the dust extraction. I had to change the star/delta configuration and otherwise replace everything with the VFD and remote . I have zero electrical know-how but it was very easy with the supplied advice from Newton Tesla.

 

[Fitzroy]

Link to Grahame's thread

 

[Brecien]

If you look at my original pics you will see the motor fitted - 3PH - and wiring - non original with added lock and panic switches plus the added wiring for the dust extraction. I had to change the star/delta configuration and otherwise replace everything with the VFD and remote . I have zero electrical know-how but it was very easy with the supplied advice from Newton Tesla.

Funny enough I have been looking at a complete package from them if I cant use the original motor. If so I will put in a slightly larger motor but will see where this route takes me first.

 

[Brecien]

If you look at my original pics you will see the motor fitted - 3PH - and wiring - non original with added lock and panic switches plus the added wiring for the dust extraction. I had to change the star/delta configuration and otherwise replace everything with the VFD and remote . I have zero electrical know-how but it was very easy with the supplied advice from Newton Tesla.

Looks cracking job and the locking caster frame a nice touch..

 

[Brecien]

The wiring niche may well have an NVR incorporated into it as you have a coil at the bottom which could well be holding a switch closed once it has received power from the start button. However, your wiring niche is not related to swapping the motor from star to delta, that would be done on the motor itself, you may already know this! Do you have a photo of where the wires from A/B/C connect to the motor, is there a terminal housing on the motor? I have seen motors labelled single voltage on the motor plate still have delta/star configuration inside the terminal housing.

Will post some photos once I find the time to get the motor out. cheers for now

 

[Fergie 307]

You can use a VFD to run the motor but the wiring diagram won't help, VFDs directly feed a motor with all isolation and switching beore the VFD rather than after. You can potentially use the original start/stop to send a run/stop signal to the VFD, but it'll take some messing.

Should be very simple, providing that the original switches are latched rather than momentary contacts, which they usually are.

 

[Brecien]

I think you and @Deadeye are talking cross purpose. The NVR (no voltage release) is a switch that releases when it loses voltage, it is being proposed to place this in the feed to the VFD. This will not change the need to convert the motor from star to delta. The only way to avoid having to change the motor from star to delta is using an inverter that takes 1P 240V and gives you 3p 400V.

The motor's plaque has only 400/440V stamped on it. I think this means it wont be easy to change the windings and therefore probably beyond an economic solution?

 

[Brecien]

Restauration ground to a halt for the moment. Got a phone call off big bruv yesterday. This years Boys weekend called off due to his declining health. You all know the score"Family comes first"
Will look at options when I get back to it! Got two other 3PH machines I want to bring back to life, Startrite table saw and a Meddings drill stand, so will look into Rotary and static Phase converters before deciding what financial road I go down.
ALL the best for know folks and thanks for all the ideas and interest.
Until were a little older
Cheers

 

[Brecien]

I think you and @Deadeye are talking cross purpose. The NVR (no voltage release) is a switch that releases when it loses voltage, it is being proposed to place this in the feed to the VFD. This will not change the need to convert the motor from star to delta. The only way to avoid having to change the motor from star to delta is using an inverter that takes 1P 240V and gives you 3p 400V.

Hi Fitzroy, Just stumbled across a post you were involved in. Converting a motor like mine to Delta Your obviously clued up on these things!! so I can use a VFD. Really great post. Nothing ventured and all that! Will take the motor out and give it a good staring at next week. Will have to order a VFD in the meantime so I can test it after the opperation. If all goes Ts up I can still use the VFD for my old Meddings Drill press.
Cheers

 

[Fitzroy]

Hi Fitzroy, Just stumbled across a post you were involved in. Converting a motor like mine to Delta Your obviously clued up on these things!! so I can use a VFD. Really great post. Nothing ventured and all that! Will take the motor out and give it a good staring at next week. Will have to order a VFD in the meantime so I can test it after the opperation. If all goes Ts up I can still use the VFD for my old Meddings Drill press.
Cheers

I work in an engineering company and have a few friendly electrical engineers whom I could bounce stuff off, I'm also willing to have a go at most things whilst employing a good amount of risk assessment. Likely this makes me dangerous rather than knowledgeable.

 

[Brecien]

Restauration ground to a halt for the moment. Got a phone call off big bruv yesterday. This years Boys weekend called off due to his declining health. You all know the score"Family comes first"
Will look at options when I get back to it! Got two other 3PH machines I want to bring back to life, Startrite table saw and a Meddings drill stand, so will look into Rotary and static Phase converters before deciding what financial road I go down.
ALL the best for know folks and thanks for all the ideas and interest.
Until were a little older
Cheers

Hi Folks, Big bruv stable and in good care.
Looked at options then found a post on here of a rewiring of a 3PH motor so enable Delta and subsequntly running the lathe on 1PH with VFD. Taking motor out next week. If I get this right, itll save me a fortune....Happy Days! Naturally Will post a running commentary with photos in the hope of it being useful to someone as it was me..

 

[Brecien]

I work in an engineering company and have a few friendly electrical engineers whom I could bounce stuff off, I'm also willing to have a go at most things whilst employing a good amount of risk assessment. Likely this makes me dangerous rather than knowledgeable.

You and me both marra! hope I dont burn the barn down.!!!
Have you any idea what baterial those lashings are made of? looks like cotton laces? Got plent small zip ties if I dont find an alterative..

 

[Fitzroy]

You and me both marra! hope I dont burn the barn down.!!!
Have you any idea what baterial those lashings are made of? looks like cotton laces? Got plent small zip ties if I dont find an alterative..

The wires are varnish insulated, once wrapped the connection points are enclosed in insulated sleeves and the bundles of wires are tied in place with string. The whole lot is then normally dipped in varnish to seal it. There are lots of youtube videos of motor rewinding if you want to see the details. I personally tied mine down with cotton string, the risk is they work loose and contact the rotor causing issues.

 

[Brecien]

The wires are varnish insulated, once wrapped the connection points are enclosed in insulated sleeves and the bundles of wires are tied in place with string. The whole lot is then normally dipped in varnish to seal it. There are lots of youtube videos of motor rewinding if you want to see the details. I personally tied mine down with cotton string, the risk is they work loose and contact the rotor causing issues.

I watched a vid of a guy doing exactly that he. Interestingly he lashed the windings down like you say using what looked like string but he used a method Ive only seen butchers do when tieing a fillet of beef or pork to form a roasting joint. fewer ends to contend with.

 

[Brecien]

SOOO here we go! Motor is out after taking a good half hour just to get the last nut and bolt out of the far corner. Witworth I presume!? But 14MM did nicely. The base plate has a rib running its width I think there to lock the bolt heads in place while you loosen the nuts from the top. Hampered in my case as Ive a short bed machine, so little space to turn a spanner never mind giving a cat a good swingage.
The Cone pulley is locked in place via a keyway which in turn seems locked in place via imperial headed Allum grub screw. A 3mm Allum key is close but will turn it into a smooth hole. so not close enough. I think the imperial version of 31/2mm is what is required. I presume the pulley must off me to advance any further. The 4 long bolts which I presume are holding the 2 ends of the motor are loose.
Luckily I've got lots of friends out here with classic British cars. Will have to ring round tomorrow to see who can lend me an imperial or witworth Allum set. Stumped until then.
Any tips on seperating the two ends gratfully recieved?

 

[Fitzroy]

SOOO here we go! Motor is out after taking a good half hour just to get the last nut and bolt out of the far corner. Witworth I presume!? But 14MM did nicely. The base plate has a rib running its width I think there to lock the bolt heads in place while you loosen the nuts from the top. Hampered in my case as Ive a short bed machine, so little space to turn a spanner never mind giving a cat a good swingage.
The Cone pulley is locked in place via a keyway which in turn seems locked in place via imperial headed Allum grub screw. A 3mm Allum key is close but will turn it into a smooth hole. so not close enough. I think the imperial version of 31/2mm is what is required. I presume the pulley must off me to advance any further. The 4 long bolts which I presume are holding the 2 ends of the motor are loose.
Luckily I've got lots of friends out here with classic British cars. Will have to ring round tomorrow to see who can lend me an imperial or witworth Allum set. Stumped until then.
Any tips on seperating the two ends gratfully recieved?

That’s where you were hoping to see six terminals rather than three, last roll of the dice, what wires are connected to the other side of the terminal block?

 

[Brecien]

That’s where you were hoping to see six terminals rather than three, last roll of the dice, what wires are connected to the other side of the terminal block?

Indeed it would have been a nice surprize. If the Info plate had somehow not been updated Haha! Not at all!! I knew what Id let myself in for, my main concern now is how do I get the two sides ends off to reveal that next step?

 

[Fitzroy]

See if Smouser comes back to you on the other thread but don't hold your breath he's not been on since Jan. Motors are all pretty similar regards dissassembly (here's a generic video). If you leave the pully on then you can't remove the rotor from the drive end head, no issue so long at the bearing is ok.

If you can take the pully off then do it so it is away from damage risk, I'd then take out the screws in each corner and remove the rods that hold the heads on the body. Next see if you can tap/lever one of the ends off, either some taps on the end of the motor arbour to try and drive it through the motor and knock the non drive end off, or a tool into the gap between shell and head on the non drive end and try to lever/tap it off directly.

Once the end is coming off beware the the rotor dropping out the bearing housing and banging on the stator inside the shell.

F.

 

[Brecien]

See if Smouser comes back to you on the other thread but don't hold your breath he's not been on since Jan. Motors are all pretty similar regards dissassembly (here's a generic video). If you leave the pully on then you can't remove the rotor from the drive end head, no issue so long at the bearing is ok.

If you can take the pully off then do it so it is away from damage risk, I'd then take out the screws in each corner and remove the rods that hold the heads on the body. Next see if you can tap/lever one of the ends off, either some taps on the end of the motor arbour to try and drive it through the motor and knock the non drive end off, or a tool into the gap between shell and head on the non drive end and try to lever/tap it off directly.

Once the end is coming off beware the the rotor dropping out the bearing housing and banging on the stator inside the shell.

F.

Thanks again for your insight Fitzroy Will take your advice and try and get the pully off today!
Watched the vid, very useful. Kind of confirms my idea of leaving pulley on (struggling to get an allum key to fit and is already mostly rounded off) If I can pull the connectiion end off after removing rods I hope to draw out the rotor with pully and motor end plate all in one as I'm not expecting any electrical connection to that end. What do you reckon? Pretty much what you said in your 1st parragraph?