Lathe Motors

[PeeWee]

Hi All,

I am about to finally look at installing my old/new/free lathe, however it did not come with a motor.  i was wondering if any of you know where in the UK is a good place to buy a motor and relevant control equipment.  Also could the motors control be used as a variable speed control?

link to what lathe i have  http://www.lathes.co.uk/faircut/index.html with the additional T slotted cross slide

thank you in advance

[bogstandard]

Ian,

I refurbished a Myforld ML2, which was very similar to your lathe. I remotored it with a 1/2HP four pole motor from Machine Mart, maybe a little on the large side, but it is still running today, and it must be nearly 20 years ago now. With it having a plain bearing head, I wouldn't go for a two pole one, it would make it a little too fast.


If you want a reversing NVR switch for it, Chester UK do one in their catalogue that would be ideal, and it is less than 20 squid. But if reversing, you must be aware that the chuck could unscrew itself under certain conditions.

For variable speed, you would be looking at a much more expensive setup, and it might not be a cost effective upgrade for such an old lathe. But the choice is there if you want to do it.

Bogs

[John Hill]

Ian, your "old/new/free lathe" gets a good write up.

I suppose that as the motor is not part of the lathe you could use whatever would do the job and there are a few possibilities.

The most simple single phase motor would be the easiest way to go although you may have to mess around with pulley sizes to get the speed within the range desired.  I presume 1/2 HP or less would be more than adequate for that lathe.  Just about any single phase motor with a start capacitor can be made reversable by someone who knows what he is doing and some will even have the required terminals ready to be connected to a suitable switch.  As far as I know single phase motors are quite unsuitable for variable speed.


Variable speed for larger machines can be easily done using a VFD ('variable frequency drive') and a three phase motor.  At least in this country 3 phase motors are more expensive new but are almost junk items when used.   A VFD is unfortunately expensive and would be the most costly part of a 3 phase VFD conversion.  Note that (if I understand correctly) a VFD to run a small 3 phase motor does not itself require 3 phase power.  A VFD gives variable speed and reversing and may also give features such as stow starting and panic stops.  I believe this is the deluxe answer for you.

A DC motor is another way of getting variable speed  but they require a PWM (pulse width modulated) or other speed control and of course a DC supply.  I bet they are expensive new but they are sometimes available cheap having been salvaged from things like treadmills.  I presume all DC motors are reversable.

PWM speed controllers are also used with 'universal' motors.  Universal because they work with both AC and DC and are easily recognised because they have brushes.  This is the kind of motor to be found in power tools such as drills, routers and all those other things that are now coming from China and cost no more than a night at the movies.  Vacuum cleaners and old Hoovermatic washing machines have the same type of motor.  One would think these would be easily reversable but when ever I have tried it the smoke has escaped although of course some are manufactured with reversing circuits (drills etc).  One might think a universal motor and a PWM speed controller would be ideal but the biggest drawback is the usually extremely high speeds and of course the screaming noise that goes with them.


For most people the choice is a single phase motor which will be single speed and may be reversable or a three phase motor with a variable frequency drive which will be variable speed and reversable but much more expensive.

[andyf]

Hi PeeWee,
As to variable speed motors, one option (assuming you aren't blessed with 3-phase in the garage, and don't want to shell out £££ on generating it from single phase) might be to try to locate a motor from a discarded treadmill/running machine. Apparently these can be found littering kerbsides in the US, but are rarer here. My faulty treadmill came from Fleabay £13.51 on Fleabay and was only 3 miles away from me. These are permanent magnet DC motors, which will run in reverse, and allegedly 1.5 or 2HP, but in reality rather less. It's usually the control electronics which have let the captive smoke out, though on mine the problem was much simpler and took 10 mins to diagnose and fix. But the preset speeds from the controller were less than ideal, so I lashed out £73 for a US made KB electronics control board from STM in Winsford, which works the motor just fine on a breadboard set-up. That's as far as my project has got at present.

So you might haunt Fleabay for a non-working treadmill, then get a control board to suit its motor. Let me know if  you follow this route, and would like any help on choosing the right KB controller to suit it.

Note added having read John Hill's post: The KB controller does the rectifying itself - you connect it to the mains with a 13A plug, and pulse-width modulated DC comes out.

Andy

[John Rudd]

I replacd the motor on my Chester 9*20 with a variable speed drive system from Drives Direct.

They advertise on fleabay and do packages...

I got a Teco FM50 and a suitable 3/4 horse motor for around £150....

As for the conversion, I've never looked back, well worth the money I spent...

(Wanna buy a relatively new but used 3/4 hp motor? )

[NickG]

I got mine for the harrison from axminster http://www.axminster.co.uk/product-Axminster-240V-Electric-Motors-29787.htm

I initially tried a 2 pole one to double up my speeds but it ran rough and didn't have the torque even though it had a lot of power. So got a 4 pole standard speed and it's really good so far. think I got a 2hp one as they say you should go up a bit if replacing 3 phase.

They are capacitor start capacitor run to give a high torque.

Nick

[PeeWee]

Thank you all for the information.

If i was to decide that getting the lathe striped and cleaned along with the new motor etc was going too far for its quaility (about to have it checked out)what would you sugest in the place, ie a C3 from say ARC or sonmthing?

Ian

[John Rudd]

Peewee,

Suggesting another lathe for you in book depends on how much you want to spend and what features you want....

Chester are doing a DV11S I think as an ex demo model for just over £1K at the moment...May be out of your price range? (If I had the money I'd buy it.. )