Jones & Shipman 540 Surface Grinder

[Smouser]

That looks good. I had a really filthy motor once (made yours look clean) and ending up washing it in a bucket of water. Took 2 or 3 weeks to dry out enough to pass the insulation resistance test.

I like the way you have wrapped the windings with sleeving. The last time I did a similar job I used high temperature plastic cable ties, but I think your solution is better. I also sprayed conformal coating over the whole lot to set it solid.

Thanks.

I have read somewhere that people used varnish to set it all solid. Conformal spray coating seems much easier.
On the previous motor, I didn't use any varnish or a conformal coating to set it all solid, just kept it as it was. That motor is still going strong.

This motor is still to be tested, maybe later tonight.

 

[fizzy]

Thanks.

I have read somewhere that people used varnish to set it all solid. Conformal spray coating seems much easier.
On the previous motor, I didn't use any varnish or a conformal coating to set it all solid, justi kept it as it was. That motor is still going strong.

This motor is still to be tested, maybe later tonight.

I have an ancient motor on a Jones and Shipman 1920s camel back drill that will need similar treatment. Outside is filthy I bet the inside is the same.

 

[Brad93]

I'll have to check with the machine on monday but your table playing up is unlikely to be the trip dogs, it's the park/trip lever on the right hand side.

 

[Brad93]

They recommend running the hydraulic motor for a couple of minutes before operating the table for the pressure to build up and get enough oil on the ways.

They ways are not hydrostatic, but yes tool and die men would turn off the oil when hitting final critical dimension,

check oil is flowing down to the Z axis ways (saddle forwards and backwards), you should see oil running out of the ends after 5 minutes or so.

 

[fizzy]

I'll have to check with the machine on monday but your table playing up is unlikely to be the trip dogs, it's the park/trip lever on the right hand side.

It moves one way fine. The other way it barely moves an inch and stops. Push down on the trip lever its fine. Bit of a chore to do that every stroke!

 

[Smouser]

It moves one way fine. The other way it barely moves an inch and stops. Push down on the trip lever its fine. Bit of a chore to do that every stroke!

Sorry, you machine is scrap.
I will collect it for parts next week.

Same as @Brad93's TV2 mill. Will collect that next week too.

 

[Brad93]

It moves one way fine. The other way it barely moves an inch and stops. Push down on the trip lever its fine. Bit of a chore to do that every stroke!

have you got 32 oil in it?

And have you checked you're getting oil to the ways by pulling the table? The rams are tiny and not that strong.

When i first got the machine and me and pete were testing it this was the issue.

Once i changed oil and got all the ways cleaned through etc, and operated the trip properly it worked perfect.

 

[Brad93]

Sorry, you machine is scrap.
I will collect it for parts next week.

Same as @Brad93's TV2 mill. Will collect that next week too.

That is going in the scrap at this rate

No one wants projects anymore

 

[Smouser]

That is going in the scrap at this rate

No one wants projects anymore

Nooo, I want it. Don't scrap it!

I can make one good one out of the two!

 

[Pawcu]

Nooo, I want it. Don't scrap it!

I can make one good one out of the two!

How do you even have space in that garage of yours? xD
You're soon going to start putting the milling machine in the kitchen as well :P

 

[Hopefuldave]

That looks good. I had a really filthy motor once (made yours look clean) and ending up washing it in a bucket of water. Took 2 or 3 weeks to dry out enough to pass the insulation resistance test.

I like the way you have wrapped the windings with sleeving. The last time I did a similar job I used high temperature plastic cable ties, but I think your solution is better. I also sprayed conformal coating over the whole lot to set it solid.

Drying out can be speeded up a fair bit by applying a low voltage to the motor's windings - did the Holbrook's by attaching an *old school transformer* battery charger to gently warm it up, did the same with the crusty Oxford welder when turning it into a 240-415 step-up for the phase converter, and a few misc motors that have had damp at them.

 

[Seadog]

Stick it in the oven. Ive done that before

 

[Smouser]

Last night I temporarily connected the motor to the VFD and entered the necessary motor parameters into the VFD.

The first run of the motor was UNSUCCESSFUL.
It was pulling excessive amps (around 7A) and the motor was turning very slow and jerky (it almost looked like a stepper motor).

I immediately realised I messed up somewhere.
The most likely problem was that I somehow misslabelled the wires.

A DELTA connection should look like this:

I previously identified the three windings correctly and used different wire colours for each winding's ends (Red, Blue, Black). However, one (or more) of the windings' ends were incorrectly marked up.
As an example, I might have marked the new cables I installed like this:
U1 as U2 and U2 as U1 which will not work as the wiring would not be like the 'triangle' in the image above.

I removed the incorrect individual cable markings and looked for some information on how to identify the start/end of windings in a three-phase motor with unmarked/unknown winding ends.

I came across this method

Seems simple enough.

For a low-voltage AC power supply, I used a doorbell transformer that I had in my electric crate.

It can either provide 12v ac or 24v ac. I connected two cables to the 24V outlet.

I decided to use A, B and C (instead of U, V and W) for the different windings and the wires would then be marked up as A1, A2, B1, B2, C1 and C2.

The Red wires = Winding A
The Blue wires = Winding B
The Black wires = Winding C


Armed with instructions and my multimeter, I set up the test.

In the above photo, I connected power to one side of winding A and also power to one side of winding B.
I also connected the other end of winding A to winding B (with the vice grip).

I then measured the voltage on winding C. As you can see I got 5.3v induced voltage on winding C.
Therefore, I could mark the red wire which received power as A1 and the Blue wire which received power as B2 as per the instructions.
Because I knew which wire was A1 and B2, I could then also mark up A2 and B1.

I repeated the test by swapping winding B with winding C and then measured the induced voltage on winding B this time.
I had the cables the wrong way around on Winding C and only got 0.3v (which I assume you take as no voltage as per the instructions) of induced voltage on winding B.

Once I swapped the two ends of winding C I once again got about 5.3v induced voltage on winding B.
Now I could mark those cables up as C1 and C2.

From here I just connected the motor to DELTA as you normally would which in my case became:

A1 + C2
B1 + A2
C1 + B2

Time to test the motor again.

The 1956 motor is running again!!


Because I am an idiot and did not mark up the wires properly, I also learned how to identify unmarked winding ends on a three-phase motor.

I then tried to get the motor back into the machine. I could not do it with brute strength. That old motor is heavy and trying to get it into position in the casting of the machine proved to be too much.
I got a piece of wood I could use as a lever to support the motor and then managed to connect the anti-vibration mounts to the machine and motor again.

 

[6ply]

@Smouser That's interesting - I wasn't aware of that (or any other) method for determining whether a winding was reversed. I might give that a go sometime as I'm overrun with motors.

Did you consider how much current two windings (in series) would pull when doing the testing with a 24 VAC supply? I presume the inductive reactance would be very low so you could use the sum resistance.

 

[Smouser]

@Smouser That's interesting - I wasn't aware of that (or any other) method for determining whether a winding was reversed. I might give that a go sometime as I'm overrun with motors.

I was not aware of a method to find reversed windings either. I had to find a method because of stupidity/necessity

Did you consider how much current two windings (in series) would pull when doing the testing with a 24 VAC supply? I presume the inductive reactance would be very low so you could use the sum resistance.

I did not. Maybe.....

 

[6ply]

I was not aware of a method to find reversed windings either. I had to find a method because of stupidity/necessity



I did not. Maybe.....

I'm guessing each winding has a DC resistance of about 6 ohms or similar. So maybe, just maybe, you had a current of around 2A. Possibly on the limit of your transformer? I'm quite happy to be corrected.

 

[Smouser]

I finally got to play with the SG again today.

With the machine standing for months there were two places oil leaked from.

The first leak was at the worm box.
I filled it up in February but it leaked so much, when I removed the drain plug, nothing came out.

I took the cover off and was greeted with this.

The thing was full of grease. The usual - if somebody see a nipple they assume it is grease and pump it full

A photo of the box mostly wiped clean.

I finished cleaning that and then turned my attention to the seal.

Visually it looked fine, but it obviously leaked very badly.

I made a new one from Flexoid.

The next leak was also at the back of the machine.

It was the same story, original seal looked ok but it was not.

Made a new one and installed it.

The head lost a bit of oil too since February and I saw it was leaking oil from the sight glass.

The original cork seal was not doing its job anymore.

I didn't have cork so I used some rubber type material for a seal and used a little RTV for good measure.

 

[Smouser]

I now have a wheel balancing jig and wanted to balance the grinding wheel.

I took the wheel off the grinder.

Only to realise I need a tapered arbor to balance the wheel

The wheel went back on and I quickly dressed it.

My second ever piece I tried to grind.

Before.

After

The finish is not great. It feels perfectly flat but it does not look very good.

I am hoping I will be able to cure that finish once the wheel is balanced.

 

[Brad93]

I now have a wheel balancing jig and wanted to balance the grinding wheel.

View attachment 476189

I took the wheel off the grinder.

View attachment 476190

View attachment 476191

Only to realise I need a tapered arbor to balance the wheel

The wheel went back on and I quickly dressed it.

My second ever piece I tried to grind.

Before.

View attachment 476192

View attachment 476193

After

View attachment 476194

View attachment 476195

View attachment 476196

The finish is not great. It feels perfectly flat but it does not look very good.

I am hoping I will be able to cure that finish once the wheel is balanced.

That's not from balancing alone. Thats the wheel hopping.

Either feed is wrong, too fast for material to be removed or wrong wheel for material type.

Or your head bearings, belt or motor mounts are bad

 

[Smouser]

That's not from balancing alone. Thats the wheel hopping.

Either feed is wrong, too fast for material to be removed or wrong wheel for material type.

Or your head bearings, belt or motor mounts are bad

Thanks @Brad93

I have zero experience with surface grinders, so every tip, possible solution, and improvement is a help.

I guess I will have to eliminate one thing at a time to determine the cause.

Is there a rough guide on how much material to remove per pass or does it vary too greatly between materials to give a 'ballpark' figure?

First, I need a pesky balancing arbor/mandrel for the wheel. They are about £125 new
Maybe I can make one but it will be hard because I don't have an existing one to copy.

I also see most wheel flanges have three weights to balance the wheel. Mine only has two

Photo of a new flange with three weights.

New ones are about £165.