Member postings for matt_ml7

I have rediscovered in a box what I assume was a car boot purchase some years back. I've found one image online of the same - a grinding and polishing head by J. F. Turner. Spindle is 1/2", 6" from base.

I've given it an initial clean up, removed rust from the pigtail and filed its threads smooth again.

I have a few old single phase motors available - a 1/2 and a couple at 3/4 HP, though yet to find any of the pulley wheels that came off them. I'm considering 6" or 4.5" wheels.

I wonder if anyone reading this has mounted similar or knows where I might find any examples or plans. Appreciate a simple motor mount is not particularly difficult to construct, but nice to see others. Any suggestions re: motor, wheel diameter and spindle speed would also be appreciated.

Edit: rather than necessarily being bench-mounted, I'm also considering a wall-mounted unit to keep the floor clear.

Edited By matt_ml7 on 10/02/2018 20:42:28

Thanks for the nudge, good point.

No, wires are all held clear of moving parts, I can poke a finger in to depress and release the plate and then twiddle the spindle a few degrees back and forward. I think I'm comfortable with it.

Thanks, Emgee.

Reassembled, motor starts and runs fine. Confirm there is a dry-sounding rub when the centrifugal switch closes again before stopping, but sounds like a clean running motor.

Thanks for the comments, all.

Matt.

Start winding measures 9.2 ohm's, switch checks out ok too. Bearings feel very smooth.

I can only really clean the contacts, tidy it up and reassemble.

If it was a break and I've shorted it by moving something, I doubt the resistance would read so well...? Also, it sounded dry/squeaky - I don't believe it's the bearings given how they feel, perhaps the centrifugal plate against the pad of the switch? I could put a drop of silicone spray on it or something.

Thanks, John.

Yeah, that would be nice. I did look into it for my wood lathe a few years ago but never got round to it. Money's tight and I was gifted the lathe, so short term I'm hoping to use one of the single phase motors I've got.

Edited By matt_ml7 on 06/02/2018 22:17:30

It's a half that was on it. Is there a disadvantage to 3/4 - too much motor? I'm not sure exactly what I've got to replace it - have to have a look...

As I have to remove the motor to install another, I will certainly open it up and take a look.

Thanks, as I expected to be fair but wouldn't it be nice to find something yet...

Thanks, Emgee/Neil.

I am told the motor may have been a replacement at some point. Without further disassembly, there is a spring switch along the inner edge of the connection board, in very good condition - the fixed end tests ok to S (yellow). Testing conductivity between there and the spring arm using pressure on the probe to open and close, it looks like it tests ok. It's closed at rest, and very clean looking.

So unless there is more than one electrically significant moving part, it must be the winding that's gone.

Hi,

I have a lathe with an electrical issue that I'm trying to diagnose. It's a Crompton 370W single phase motor. The owner's son in law told me there was water ingress at the sockets on the wall and last time the lathe was used there had been a pop/flash - I don't know where it was.

Initial checks:

• spindle turns freely - sounds a bit dry.
• plug fuse (5A) - ok.
• connectivity from plug to switch housing - ok
• switch housing - some damp internally, dried out
• overload cutout was tripped, now reset - ok
• locking mushroom Isolator, one terminal badly corroded, return spring fallen out - now repaired - ok

I tried powering it up, the motor hummed for a second or two then blew the 5A fuse. I replaced the fuse, tried again spinning the motor shaft by hand just before powering - same, hummed for a second or two then blew the 5A fuse. In hindsight, I might have performed the checks below before powering it up.

I unplugged and removed the cover plate on the back and noted the wiring:

• motor BLUE --- Z2 --- supply NEUTRAL
• motor YELLOW --- S
• motor BLACK --- U2
• motor RED --- U1 --- supply LIVE

Additionally:

• link wire U1 --- S
• link wire U2 --- Z2

The label on the inside of the cover plate:

• BLUE --- Z2 --- START
• YELLOW --- S --- START
• BLACK --- U2 --- RUN
• RED --- U1 --- RUN

So I assume U1/U2 is the primary winding, S/Z2 the start winding. There are no capacitors.

I removed the supply LIVE and NEUTRAL wires and both link wires.

• U1/U2 measures approximately 5 Ohms.
• S/Z2 measures as an open circuit.

My limited knowledge suggests the wiring is correct and either the start winding has burned out, or the centrifugal switch is in a failure state.

Can anyone help? Do I disassemble to inspect the switch and measure start winding resistance beyond it?

(I overhauled a similar motor a number of years ago and have a couple more sitting, so subject to shaft diameter for the pulley wheel, I may have a spare.)

Thanks, Pete.

Ah, thanks Andrew.

The item below was attached to the lathe bed casting, just to the right of the left-hand lead screw mount - it carried the switch box, I assume installed by the previous owner.

The part itself cannot be seen in the next picture, but here's the install location:

I don't know if he drilled and tapped the holes in the base himself, or if this is simply how the gearbox usually mounts. I've been unable to find any images online that answer this.

Can anyone help?

Well said - they said it was well looked after. Unknown how long he had - it may have been obtained when his employer closed, or not. I am very fortunate to have received this.

There are no broken teeth - the topslide micrometer dial is bent so it will need to be flattened - I'll clean up the bed and cross/topslide ways. The counter shaft is dry, main spindle is not awful, leadscrew is beautifully smooth.

Nevertheless a good list of things to do before powering. Electrics known to be faulty due to water ingress at the sockets.

A fair point. It was used a lot to turn wood, so there's a lot of oily sawdust both on the surface and in the cavities. Most of that should clean off readily.

Earlier, I realised I could do with it running to make a tool to press the Jacob's chucks apart.

Cheers, Neil.

4-jaw came off with hand-pressure on the belts and a spanner to a large hex nut in the jaws.

It stands out like a sore thumb, doesn't it - embarrassed I even took the photo like that.

Thanks, Don. Great stuff!

Useful lubrication and inspection charts in the Yahoo group, as well as the scan of the manual.

I've contacted the previous owner in case we have missed any small parts. It would be a shame for anything to be separated at this stage.

Thanks, Neil/David!

Thanks, John. I've got two books to hand - The "M.E." Lathe Manual by Westbury (1951) and How to run a lathe by O'Brian (1942/2013), neither specific to the ML7 though.

Yes. It's hard to imagine anything but a full tear-down at which point everything gets cleaned and re-protected. I'll put your comment up on the wall.

Hi, all.

I collected a Myford ML7 today along with a number of accessories. Serial number suggests 1952-53. I've been recommended this forum as somewhere I might seek help if needed.

I've never used a metal lathe before, though I've spent many (many) hours watching videos of both casting and machining. I made a conscious decision a few years ago not to go looking for one, but this week one came to me. The gentleman owner passed away last year and on a mutual friend's recommendation, his daughter has very generously gifted it to me.

I own a few older machines already - a Pacera drill press I use regularly, a Milford wood lathe a Wilkinson cabinet saw both currently in storage. It's mainly wood I've worked with - just a hobby but relatively well equipped. The unexpected additional of the metalworking lathe to the workshop is wonderful.

Due to its current condition, it'll be a while before it's ready to run, but restoration is half the fun!

Any pointers towards particularly helpful resources would be appreciated.

Best wishes,

Matt.