Single phase motor manufacturers

Hi, I just picked up a three phase Fobco star that I intend to fully restore and convert to single phase. Im currently shopping for a motor and I'm wondering what people would suggest?

Ive seen Tec, Marelli and lots of no brand mentioned motors at various price points but I'm not sure if there will be much difference between makes?

Im thinking a 0.55kw will do but Im hoping this drill press and motor will last me many, many years so I'm happy spending a little more if a more expensive motor will give me less vibration and noise.

I made the mistake of buying a JET drill press a few months ago (it was soon returned!) that had a motor that practically wobbled the vibrations were so bad so I'm a bit on edge about getting a good one for this fantastically solid Fobco drill.

Thanks all

.

Sounds like the one Robin Graham on here bought ?

wasn't from Axminster by any chance ?

It was indeed from Axminster, a Jet JDP-15. They actually replaced the first one and the second was just as bad so I returned it for a refund (Axminster customer services were great). I hope they didn't sell them on again to anyone, they are not fit for purpose in my opinion.

Congrats on the drill. Does the original 3 phase motor nameplate say something like 240/380V on it anywhere? If so powering it by inverter is the way to go for smoothness... with the bonus of variable speed so fewer belt changes...

Its a 380/440 brook crompton motor. I was under the impression you lost a lot of power with an inverter? Im more at home with mechanicals and paintwork than electrical so forgive my ignorance.

Hello Nick,I have a single phase motor ex Fobco Star and need a 3 phase. I've sent you a PM. John.

Nick,

I changed the 1-phase motor on my machine for a 3-phase and Inverter and it transformed it out of all recognition.

No more belt changes trying to find/guess the correct speed for drill bit, as now I just twiddle the speed pot and adjust pressure until a clean spiral of metal comes out the flutes as it cuts.

Low speed for largish drill bits (1/2", csk and c'bore work is now an absolute doddle and pleasure to do.

I keep wondering how I managed beforehand.

3-phase with Inverter is without doubt THE way to go on all but basic machines.

Only my Excel filing machine & small high speed drilling machine are without.

Geoff - FeedRodMotor day today, at last!

Geoff, PM awaiting you in your inbox.

Come on man - stop slacking !!

LOL

Give me a break young man

Just wait till you reach my tender age and then think back and weep at what you where then capable of doing.

By comparison to what I could achieve when I was your age and now, it seems as if I did so at light speed.

Geoff - I now look back, shake my head in dismay and weep.

Well I think you have convinced me an inverter is the way to go. The 500rpm low speed on the Fobco star had concerned me so being able to dial that down electronically would be fantastic.

Not sure if this will work but the link should take you to an earlier thread on this forum showing Fobco with VFD

Ian P

**LINK**

Mmm, despite having initially suggested it and despite the many benefits of inverters (very efficient BTW, high nineties percent - you may have been thinking of static or rotary converters which are less so) IMO there may be a good argument here to come to an arrangement with John who has a suitable single phase motor to swap.

First, if your motor is 380/440V, it won't run properly off a straightforward mains-powered (240V in, 240V out) inverter. There are ways round this from the complex (inverters with built-in voltage step-up exist, or you could use a step-up transformer then a 380V in, 380V out inverter, or even fiddle around with the motor's internal wiring to reconfigure it for 240V) to the simple (get a replacement 240V three phase motor) but either way it is hundreds of pounds of expense more than just swapping to a single phase motor.

Secondly, if you're not at home with electrics but go the inverter route anyway you could be fiddling around a fair bit before you have a working drill...could be a fun challenge/project of course if you're up for it.

Otherwise, unless the cost of a three phase package (various suppliers do them, safely pre-wired) isn't an obstacle, I'd consider going single phase initially, get the thing going, but read up on inverters etc and watch Ebay for motor and inverter bargains, with a view to converting to three phase yourself in due course.

We may wax lyrical about the benefits of three phase but a single phase drill is perfectly serviceable and the Fobco should be a joy to use however it's powered IMO.

Having cleaned off more dirt I see the motor now lists 380/440v and below that says 220/250v so I assume it is dual voltage after all?

Im in no hurry to get the drill working, id rather take my time to explore the options and learn the skills needed to get it right first time. I'm planning a long slow restoration to get it looking better than new. I enjoy restoring things as much as using them to be honest!

I am not at home with anything beyond basic electrics but I do have an ex engineer next door and an uncle thats an electrician so I have help at hand. The pre wired packages on eBay look good and it removes the problem of adapting the shaft size of a new motor to fit the old pulley.

Thank you for the thread link Ian, that really does look fantastic. Makes me want a three phase grinder now too!

Yes, dual voltage it is! Changes the picture a bit - now your motor can be hooked straight up, and with the additional help on hand too I'd say go for it

While researching VDF inverters and control pendants I came across some vague mentions of them sometimes using asbestos insulation in old motors.

The Crompton Parkinson motor I have on the drill says it has class E insulation. When I’ve looked that up online it doesn’t mention that asbestos was ever used for class E so I assume that means the motor is 100% safe?

We had some trouble with finding and having asbestos professionally removed in this house so I have been over paranoid about it ever since. Spent a fortune removing the stuff so I do not want to run any risk of introducing any more.