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Progress with my lathe.

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Ash Small

Wed Jun 17 2015, 08:37PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

I finally lifted the bed of my lathe back onto it's supports today, after being stored in an outbuilding for years and in my drive since last summer. I still need to clean it up, set it all up, bolt on the 'missing bits' (motor, etc).

It was made by Pffeil of London, who produced these during the late 19th century. I believe they went out of business around 1910, so it's well over a hundred years old.

Ash Small

Fri Jun 19 2015, 08:51PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

Well, I've cleaned it up a bit, fitted the intermediate drive shaft, and I thought I should sort out some 'proper' switches this time (in the past it's just been plugged into a switched socket).

The MEM switchbox comes courtesy of Dr Slack, and I think I've left enough room on the 'switchboard' for coolant pump switch, and maybe a light switch as well. Not sure where I got the 'STOP' button from. A skip in a place I used to work, I think, but I've tested it and it works. Maybe I should fit a warning light to indicate when it's been operated? it seems to be wired for it, or maybe it's wired to operate a relay? There doesn't appear to be a current rating on it, but the terminals look good for more amps than the motor will draw. I figure a relay is just one more thing to go wrong.

Next job is to clean up the motor before I re-fit it and wire everything up. I'll be using the old drive belts initially, as I think I need to strip the headstock to replace the secondary belt. I thought it was going to fall apart 25 years ago, but it just seems to keep going. They don't make them like they used to

The only link I've found on the internet on Pfeil lathes is this one, which shows how the original treddle mechanism would have worked, although the lathe shown is a more basic model than mine.

Dr. H.

Sat Jun 20 2015, 04:23AM

Registered Member #931 Joined: Mon Jul 30 2007, 05:25PM
Location: Bulgaria
Posts: 486

Hi Ash,

beautiful machine

I am glad you are taking the time to restore it and not throw it for scrap metal (as many nice machines have that fate these days).

Ash Small wrote ...

Next job is to clean up the motor before I re-fit it and wire everything up. I'll be using the old drive belts initially, as I think I need to strip the headstock to replace the secondary belt. I thought it was going to fall apart 25 years ago, but it just seems to keep going. They don't make them like they used to

Amen to that

I can't understand how it is possible with the progress of new materials and manufacturing techniques to be produced such garbage today....

Cheers and keep us posted.

Ash Small

Sat Jun 20 2015, 09:58PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

You can say that again, this is seriously over-engineered. I've used it almost exclusively for stainless (tried monel a few times too) and I've really abused it. I did crack a casting once on the gearing for the screw feed (change wheels), I've not got to that bit yet

I've decided, as I need to wire up the switches, to re-wire the motor too (see photo). What I can't decide is whether I should use 'armoured cable' (the stuff with the strands of steel around it), and the appropriate earthed glands. It's not a lot more expensive than the normal stuff.

Hazmatt_(The Underdog)

Sun Jun 21 2015, 12:04AM

Registered Member #135 Joined: Sat Feb 11 2006, 12:06AM
Location: Anywhere is fine
Posts: 1735

I'd get a heavier cord on the motor, instead of the Vacuum cleaner cord..hehehe.
And get some proper lugs on the wires there, that guy is a fire hazard.
If you had a 90 degree elbow strain relief exiting the housing you'd be fine.

Sulaiman

Sun Jun 21 2015, 03:05AM

Registered Member #162 Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3141

although i would be inclined towards putting ring crimps, cable supports etc.
my first concern would be the integrity of the insulation of the original wires
which may be (look like) natural rubber, which time, temperature, atmospheric oxygen and OIL tend to degrade.
(plasticised pvc was not invented until 1926, and pvc insulated wires were not in general use until the 1950's)

I would 'megger' at at least 500V the insulation of the wires with respect to the frame.
no point adding excellent external wiring if the internal wiring is 'leaky'

Ash Small

Sun Jun 21 2015, 12:56PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

Thanks for the feedback I've already removed the 'vacuum cleaner lead' (the reason for taking the photo was as a reference when I re-wire it) and managed to screw a metric plastic compression gland into the old imperial thread (it cut it's own thread in the plastic).

I've not seen my Megger for a decade or so. I assume you are referring to the internal motor wiring, Sulaiman. I'm tempted, at present, to just disturb the internal wiring as little as possible, and make sure the motor is well earthed. I don't want to strip the motor at the moment and replace internal wires, etc. Maybe I'll look for a cheap DMM with 'insulation testing' function? (I will strip the motor if the consensus here is that I should, there are probably some bits of swarf inside anyway)

My current plan is to open up the gland hole to take a 20mm brass gland, and fit some 2.5mm steel re-inforced armoured cable (is it known as 'SWA'?). I also plan to run some four cored armoured cable to the STOP button. It has two switches inside, one that switches 'off' and one that switches 'on' when the button is operated. I plan to use the one that switches 'on' to operate a warning light......Hang on a minute, I only need three core, one 'positive feed', one to the motor, and one to the warning light. .....That will save buying four core as well.

Hazmatt_(The Underdog)

Sun Jun 21 2015, 04:22PM

Registered Member #135 Joined: Sat Feb 11 2006, 12:06AM
Location: Anywhere is fine
Posts: 1735

Is it possible to wire in a reverse switch on that motor? Or do you have a reverse gear on the lathe already?

I have a motor that came with my Atlas and somebody wired in a reverse switch, but I think you have to have access to the field winding... I could check into it when I have some time.

hen918

Sun Jun 21 2015, 07:21PM

Registered Member #11591 Joined: Wed Mar 20 2013, 08:20PM
Location: UK
Posts: 556

Ash, FYI the extra contacts on Emergency stop buttons are usually used to tell a PLC or other controller that the E-stop is in, but could be used for anything within its current rating. SWA stands for Steel Wire Armoured, however I would go for "SY" cable which is a similar braided, flexible cable designed for just such machines.

Ash Small

Sun Jun 21 2015, 07:38PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

Hazmatt_(The Underdog) wrote ...

Is it possible to wire in a reverse switch on that motor? Or do you have a reverse gear on the lathe already?

I have a motor that came with my Atlas and somebody wired in a reverse switch, but I think you have to have access to the field winding... I could check into it when I have some time.

I can reverse the leadscrew using the change wheels. I can't see any reason why I'd need to reverse the chuck rotation, except possibly when using a tailstock die holder, but I usually rotate it by hand when using taps and dies.

EDIT: You do want to reverse the drive if you are cutting a thread in more than one pass, as it enables you to keep the tool synchronised with the thread, so it should be worth implementing a reverse switch if it's simple to do.

EDIT: I've just been reading up on AC motors, and I'm none the wiser really, there are so many different types. If it's a 'universal motor' I'd expect the rotor and stator windings to be in series, but this motor seems to have two parallel windings (or two sets of windings). I suppose I'd have to open it up and post photo's if I want to ascertain what type of motor it is.

Does this tell us anything?

It seems to draw more current than a current Brook Compton capacitor start motor of the same power. 2.3 A comparesd to 1.75A.

A current capacitor run motor draws 1.3A. All motors rotate at the same (nominal)1500RPM. (actual around 1420-1430)

I'm guessing from this that it's probably capacitor start, but I'm only guessing at the moment.

EDIT: Found this, from 1957, which seems to have my motor on it:

From what I've read, Mine was produced somewhere between 1961, when BS 2048 came in, and 1967, when the company name changed to Brook Victor.

EDIT: I think I found what I needed to know. A1, A2 is the main winding, Z1,Z2 is the start winding, and, if reversed, should reverse the direction of the motor.

It's not obvious which wires are which, though. It will require a bit more investigation tomorrow.

I guess I'm not quite ready to buy the cable, glands and switches yet. I'll have to do a diagram, it's getting more complicated all the time, but I may have a look inside the motor tomorrow.

EDIT: Found this as well

EDIT: This link was useful, looks like the red wires are Z1 and Z2.

It has a centrifugal switch inside for the start winding.

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