Variable Speed Controllers for Lathes

[John Wood1Participant @johnwood1]

[John Wood1Participant @johnwood1]

I want to add a variable speed control system to my Warco WMT300 lathe – ‘cos I’m fed-up with the present long winded belt change method.  Part of this is that it would provide an opportunity to change the motor to a 3-phase one and so provide the additional benefits which that would bring.

 

I am looking at the Newton Tesla CL series that, with a 1hp motor would seem ideal, but, Drives Direct can also supply a 3-phase motor and inverter which, as far as I can see at the moment, will do the same job. The price of the Newton is around £425 but I havn’t enquired about the Drives Direct one.

 

Has anyone any experience of these systems please?

 

Many thanks,  John

[Michael FreemanParticipant @michaelfreeman10443]

Hello John. 

 

I recently refurbished a Myford ML7 and covered the rebuild on my website  www.mikes-models if the ink doesn't work.

 

I fitted a new 3 phase motor from Direct Drives who advertise in the magazine although I found them on eBay. I must say I have not regretted it al all and am very pleased to be able to control the speed. The only issue I have had is that if the wife has the cooker on in the house and other items such as washing machine etc, it can trip the RCB. I beleive from others that this is not uncoommon. the amount of times this has happened has reduced virtually to zero if I am aware of the load already placed on our domestick supply.

 

The support via telephone frome Direct Drives was excellent and I have no hesitation of recommending them (I have no link to them other than a customer).

 

As I said you can see some detail about my experience on the website or my blog  

 

Kind regards, Mike 

Edited By Michael Freeman on 22/07/2009 14:02:29

Edited By Katy Purvis on 01/06/2015 09:46:38

[Dougie SwanParticipant @dougieswan43463]

I recently fitted an inverter to a Harrison M300 that I bought from drives direct, it has worked faultlessly. I actually bought it on ebay with a saving of around £100 from the list price and I would agree that the telephone support is excellent

Regards

Dougie

[David Clark 13Participant @davidclark13]

Hi there

The next Model Engineers’ Workshop, 154 has an article about fitting an inverter to a Harrison M300.

regards David

 

[Steve SparrowParticipant @stevesparrow87985]

Hi John,

 

A few years ago I wrote an article for ME on inverters / converters to try and make things a little easier. The article can be seen on my website at this location –

http://www.steamplates.co.uk/Inverter_Vs_Converter.html

 

Regards

 

Steve

[WALLACEParticipant @wallace]

One thing I’ve never seen mentioned is using a single to three phase inverter to power more than one machine (not at the same time !).

 

I bult one a few years ago from an Elektor design  – although I up-spec’d a few components   so it would deliver a bit more power. It’s on a ‘3 phase ring main’ around the workshop with each machine having a big relay to isolate it when not in use. There’s a seperate control box on each as well with the direction and speed controls – this is linked back to the ocnverter on what I suppose you could call a ‘control ring main’.

 

Each control box has a phono socket on it – to take control, I just plug in a coresponding plug. There’s only one which means I can’t have more than one running at a time !

 

Works a treat.

 

WALLACE 

[John Wood1Participant @johnwood1]

Thanks to all for the postings which has pointed me in the right (I hope) direction. I went for the Newton Tesla system which is now up and running and, so far, I am very pleased with it.

 

For the Warco lathe it did need a bit of fettling because I chose the Italian motor rather than the Chinese. The Italian one has a different mounting so I had to fabricate fittings in order to fit it to the existing motor mount. Also this motor has a 19mm shaft so I had to bore out the original motor pulley to fit. Otherwise  all went very easily.

 

The company was very helpful and the whole experience can be recommended to anyone contemplating a similar upgrade.

 

Now then, what shall I do now…..!

 

John

[John Wood1Participant @johnwood1]

Just an update. 

 

I have used the new controller system for several weeks now and find it to be a delight to use. Very little belt changing now for different speeds, only for the very high and rarely used speeds. The torque remains constant even at the lowest speeds, it helps greatly with screwcutting and the ‘nudge’ feature is most useful. After a while you begin to wonder why you struggled all that time when the solution was so easy. The cost of course is the obvious answer.

 

John

[Jim KParticipant @jimk]

I have often wondered about these and also for using it in my Boxford. What i was wondering is, do you still use the pulleys for the different ranges of speeds or do you configure the pulley system so that you have a sort of direct drive?

Has anyone ever done it to a boxford.?

JimK

[John Wood1Participant @johnwood1]

Hi Jim.  Because of the wide speed range of the new controller I find that I can leave the speed change belt on the lathe in a medium setting as for the original motor, I can then vary the spindle speed from virtually nothing to faster than the original without changing belts and this has been fine for all my work so far. Of course you can still do your original speed changing if you need to change ranges.  I have also calculated the approximate spindle speeds achieved at various settings of the coltroller although this would alter if I changed my belt/pulley combination.   Sorry but I have no experience of the boxford.

 

Regards,  John

[Jim KParticipant @jimk]

John,

thanks this answers my question.

JimK

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