# coronet major lathe



## joethedrummer (29 Apr 2013)

Hi and hello to all woodspinners, this is my first post and you might hope it is my last!!
I have a pre 63 coronet major which i cannot get slow enough for bigger bowl turning.
I am thinking of creating a layshaft to reduce the speed. There used to be one of these available as an option,, has anyone seen one and could describe it? . 
Or have you got any better solutions ?
Best regards ,,,joethedrummer


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## thomvic (29 Apr 2013)

I have a similar lathe. I replaced the original motor with a 3 phase one and bought an inverter. I now have full variable speed without switching belt pullies and have maintained excellent torque.

Richard


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## Robbo3 (30 Apr 2013)

Date unknown but Figures 29/30 show the speed reducing countershaft & its assembly.


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## inaspin (30 Apr 2013)

Hi Joe
Welcome to the forum i have got the speed reduction pulley that you are enquiring about and would be happy to email you some photos and any other details that you require. You need to make a couple or so more posts before you can pm me but as soon as you can , pm me your email and any details you want and I will dig it out and send you.

Regards Berns


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## joethedrummer (30 Apr 2013)

Hello,,Richard,,Robbo,,& Berns, 
I am just "knocked out" by the help you fellas are giving ,, I will digest all your information and get back to you all.
Many many thanks,,joe


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## dickm (1 May 2013)

Only hearsay, but think I've read somewhere that the reduction gearbox for the Coronet is *horribly* noisy. But adding ear defenders to the essential respiratory protection isn't difficult!


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## joethedrummer (2 May 2013)

Hi good fellas,
Richard,, I can see many benefits from your solution,,but the initial cost of the parts make this a pricey way forward but I will see if I can source parts more cheaply and try to find a tame electrician to price the install,,
Robbo,,thanks for the pics of the countershaft etc,,I have found the mounting hole in the back of the headstock and I"m now fiddling about figuring out sourcing parts for building one,,
Berns..thanks for your kind offer,, I will certainly PM you ;(Berns for PM I say); when I am able,,re the bearing arrangement for the pulley and pulley sizes , etc,,
Dick M,, I read that somewhere as well, but getting hold of a reduction gearbox might entail a visit to a museum somewhere !! The wife has taken to wearing my ear defenders,, C"ant think why !!
Regards,,joe


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## joethedrummer (17 May 2013)

hello once again,,3 phase and the inverter is quite expensive but i can see its attraction,,sooooo,, i have started to create my own layshaft with the help i received from you good fellows ,,
i have procured a double needle roller assembly with a 16mm spindle and some bar which i hope will carry the bearings via a bearing block in the right area for the 2 step pulley ,,
i would really appreciate your feedback on my progress so far "don"t hold back",,
i will try to add a picture,, might be gone a while,,

best regards joe
the photo file is too big ,,,,helpppp


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## joethedrummer (18 May 2013)

hopefully , we might see a picture or two






:?


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## joethedrummer (16 Jul 2013)

Hello all woodspinners,,had the welder out yesterday and welded up the counter shaft,, assembled it onto the lathe and it works a treat,, the twin pulley came from RDG and gives a reduction of 2.5 : 1,,so i have ended up with a bottom speed of about 480 rpm; , a better speed for larger dia: work than the 1200 rpm: ,,
Now off to make chisels meet spinning wood !! next message could be from the local hospital :?


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## Phil Pascoe (16 Jul 2013)

It might be, if you don't make a cover for it.


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## Paul.J (16 Jul 2013)

and i'd put some steel mesh on those windows in case a lump of wood decides to leave the lathe??


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## Robbo3 (17 Jul 2013)

I like that.
Also agree with the comments about guarding.

Is the saw table height adjustment wheel mounted vertically to take up less room?


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## joethedrummer (17 Jul 2013)

Hi Robbo,,thanks for your past help,, yes the saw bench and planer are under the bench out of the way so i tipped the height adjuster up so i can use the tool post stand when the headstock is turned 90 degrees,, Have taken on board your advice re the guarding,,


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## Northerner (17 Jul 2013)

If you ever hear of a short tool rest and the stand that attaches to the leg for turning with the headstock rotated, let me know please! Seems to be the only bits missing from my Major. The projects looking good - if you need the mortising attachment I have one with mine that I'll never use.


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## joethedrummer (18 Jul 2013)

Hi,, Stiles and Bates in Kent make some nice short tool rests,, so nice I copied them and made a set for myself (man and shed syndrome ),,can"t help with the stand "cos I think my Coronet is earlier than yours,, but ( here we go again ) I made a remote stand which I"ll photo and post if you want it might give you an idea,,
Lets have some pics of your finished machine please,,


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## joethedrummer (18 Aug 2013)

Hello woodspinners,,,
Took all your advice and made some guards,,, ( good job you are here to curb my actions),,
joe,,,


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## vindyboy (22 Oct 2013)

Hi Joe the drummer
Just found your pic of the speed reduction set up.
I have a Major mk3 and want to reduce the speeds to enable screw thread making for a repair I have been asked to do.
I can see from your pic that in essence the pulley goes between the drive and driven pullys on the lathe but cannot see the pattern or size of the pulley. I wondered if you could let me have pics showing the pulley looking from the side together with any measurments of actual pulley diameters.

I would like to have a go at turning the pulley, in wood, as I already have a bearing block that I could use to mount it.
Alternativly was 'RDG' the model making supplier in Yorkshire?

Hoping you can help
Thanx
Nigel


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## WoodySteve (22 Oct 2013)

i use a lathe speed controller on my coronet hobby lathe, works a treat. get them on ebay ,


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## Jaypee (22 Oct 2013)

Hi WoodySteve, which motor do you have on your coronet hobby lathe? I have a Major with a Brook Crompton 2850rpm 1hp motor, think it's rated at 6Amps. Someone told me a while ago that some electronic speed reducers can make the motor buzz and get hot and lose some power/torque. Sounds like a great solution for speed reduction but would hate to ruin a good motor and have the hassle of trying to source another or have it fixed. If yours is the same motor I might give one of those gizmo's a whirl if you say yours works fine. 
Cheers
Jaypee


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## WoodySteve (22 Oct 2013)

Jaypee":2mjdpn8d said:


> Hi WoodySteve, which motor do you have on your coronet hobby lathe? I have a Major with a Brook Crompton 2850rpm 1hp motor, think it's rated at 6Amps. Someone told me a while ago that some electronic speed reducers can make the motor buzz and get hot and lose some power/torque. Sounds like a great solution for speed reduction but would hate to ruin a good motor and have the hassle of trying to source another or have it fixed. If yours is the same motor I might give one of those gizmo's a whirl if you say yours works fine.
> Cheers
> Jaypee



Hi Jaypee, I will have a look tomorrow and let you know as im not 100% sure as i have never looked at the motor, ive not had the coronet hobby lathe long, but i brought the lathe speed controller from ebay 3 weeks ago and never had any buzzing from the motor, i plugged the lathe lead in the socket and the plug in the main socket and away it went no more swapping the belt.

http://www.ebay.co.uk/itm/121195468533?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

cheers
steve


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## Phil Pascoe (22 Oct 2013)

It specifies that it will not control induction motors - I can't say I've come across a lathe with a brush motor.


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## joethedrummer (23 Oct 2013)

vindyboy":2vagq2sn said:


> Hi Joe the drummer
> Just found your pic of the speed reduction set up.
> I have a Major mk3 and want to reduce the speeds to enable screw thread making for a repair I have been asked to do.
> I can see from your pic that in essence the pulley goes between the drive and driven pullys on the lathe but cannot see the pattern or size of the pulley. I wondered if you could let me have pics showing the pulley looking from the side together with any measurments of actual pulley diameters.
> ...


Hello Woodspinners,,
Nigel,,yes RDG from Yorkshire supplied a twin pulley which was for a Myford super 7,,it is 4 3/8 and 1 3/4 inch diameters so gives a 2.5 to 1.0 reduction,,,I could not find a twin pulley giving a greater reduction with the bore size I needed,,,I suspect you will need an even slower speed than I acheived, for thread chasing ,,,so making a wooden twin pulley will give you the oppotunity reduce more.
There is a pic; earlier in the thread of the back of the pulley I used.
I have turned some bowls up to about 13 inches dia: with my set up,, but now of course want to try something bigger,,so I"m toying with having an ali: pulley turned up to give a greater reduction,, tho" there will come a point when the lathe is just not man enough !!.
Steve has found a neat solution for £25 on ebay giving infinite variation,,but like Jaypee, who has the same motor as me, I am a bit wary of damage to the motors,, "cos when I spoke to a buddy who rewinds/repairs electric motors he did a lot of "sucking thro" his teeth " when I spoke about refurbing mine if it gave up the ghost,,
Hope that helps,, maybe I should just take up knitting,, it"s got to be easier !!!
,,,,,,,,,,,,,joe,,,,


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## WoodySteve (23 Oct 2013)

Jaypee":vgtixlxd said:


> Hi WoodySteve, which motor do you have on your coronet hobby lathe? I have a Major with a Brook Crompton 2850rpm 1hp motor, think it's rated at 6Amps. Someone told me a while ago that some electronic speed reducers can make the motor buzz and get hot and lose some power/torque. Sounds like a great solution for speed reduction but would hate to ruin a good motor and have the hassle of trying to source another or have it fixed. If yours is the same motor I might give one of those gizmo's a whirl if you say yours works fine.
> Cheers
> Jaypee



same as your motor Brook Crompton 2850rpm 1hp motor.


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## WoodySteve (23 Oct 2013)

phil.p":37ygc5aa said:


> It specifies that it will not control induction motors - I can't say I've come across a lathe with a brush motor.



thats what it says on ebay description, it works on my Brook Crompton 2850rpm 1hp motor, 
alot of mini lathes have brush motors, not sure on the bigger lathes,


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## CHJ (23 Oct 2013)

The device is for the control of Universal Motors, those with commutators and brushes such as electric hand drills.

They work by using an SCR or Thyristor to clip the AC waveform to limit the power available, main problem with the simpler circuits is the loss of torque at lower speeds/power settings, those with more advanced circuitry use the EMF feedback from the motor to adjust the waveform output to compensate somewhat for this limitation.

Using one with a single phase Induction motor will not slow it down as it is frequency dependant not power dependant, If an induction motor is showing a speed change it can only be that it is loosing rotor sync and slipping with loss of torque.
Under these conditions there is serious risk of the induction motor overheating as it is not producing any feedback to control the current input and is relying on source limiting.

An induction motor can take up to 10 times its running current when starting until it is up to speed, anything that stalls its rotor and brings it back into its starting configuration will be bringing it back into this high current consumption mode.


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## vindyboy (23 Oct 2013)

Ta ever so for that Joe
Sounds like it's not a good/safe idea to use a speed reduction gizmo so back to the chiselling.
Nigel


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## Jaypee (24 Oct 2013)

Thanks CHJ for your detailed description of the electronic speed reduction gizmo, far more eloquent than my mates evaluation, he described it as a ' nasty wave chopper that will eventually b****r your motor!' So I will give it a wide berth, I reckon trying to find replacement twin shaft Gryphon motor would mean a trip to the 'Hens teeth and Rocking horse poo shop!' I have the updated/later 5 speed multi rib pulley set up fitted and this gets me down to 750ish rpm so on the rare occasions I need to spin a large bowl I sharpen the tools and go steady, not had any issues to date.


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## CHJ (24 Oct 2013)

The ultimate speed control system is to fit a 3 phase motor and an inverter, not a cheap option unfortunately.
The only consolation being that with the existing pulley ratio selection to give you the torque you can get away with a reasonably small HP motor and inverter.


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## WoodySteve (24 Oct 2013)

CHJ":i7umijue said:


> The device is for the control of Universal Motors, those with commutators and brushes such as electric hand drills.
> 
> They work by using an SCR or Thyristor to clip the AC waveform to limit the power available, main problem with the simpler circuits is the loss of torque at lower speeds/power settings, those with more advanced circuitry use the EMF feedback from the motor to adjust the waveform output to compensate somewhat for this limitation.
> 
> ...




Thanks for the advice. Today i was out doing some turning and i thought the motor was getting hotter than normal, so ive disconnected that lathe speed controller. im just hoping ive not damaged the motor,


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## EnErY (26 Oct 2013)

Paul.J":2uj1dtfc said:


> and i'd put some steel mesh on those windows in case a lump of wood decides to leave the lathe??


Certainly worth it also thought :lol: :lol: :lol: :lol: :lol: :lol: 
Regards
Bill


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## joethedrummer (26 Oct 2013)

EnErY":1wgnplut said:


> Paul.J":1wgnplut said:
> 
> 
> > and i'd put some steel mesh on those windows in case a lump of wood decides to leave the lathe??
> ...


 HI EnErY,,,,I did put some guarding over the windows and the pulley arrangement,,,see previous piccy,, and tho" i"ve turned a few bits up to about 13 inch diameter nothings come adrift so far,,,,but only time will tell,,,it may happen,,,have I got a choice between grapes or a wreath,,,,tee hee,,,
,,,,,,joe,,,


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## vindyboy (26 Oct 2013)

Hi all
Can anyone confirm whether or not all Coronet models are based on the same diameter bed size ie 2 inches
? so that say bed platform fittings from a minor would also fit a mojor??
vindyboy


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## Jaypee (27 Oct 2013)

Hi vindyboy, I think the only difference between Major and Minor beds is the Major has a machined slot at the rear to self align the saddles and the Minor is plain round bar. Got some Coronet paperwork somewhere, will dig it out and see if there's anything on there to confirm.


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