surface rust

[Harry Bloomfield]

so I could just attach t to a 12v car battery ? don't want to blow the garage of the side of the house, that's the type of stuff the wife gets her knickers in a knot over.

You could, but the battery would be discharged - the charger connected would be charging, whilst the electrolysis was taking place. By itself, a modern charger will not output any voltage unless it first 'sees' a correct polarity voltage connected across it.

 

[Deleted member 174758]

... not really sure what the bits are for, not sure if they are for the milling head or the lathe, some have mortise tapers others round - exciting days ahead

They look like reamers (hence the square shank ends - they are held in tap handles), so not milling tools at all. They are the one type tool you don't want to get rusty, or change the size of by using abrasives on them

 

[Burnerman]

Hand held reamers they are, but you can get a Jacobs chuck for your tailstock if it’s there which will hold them.
The rotating, or Lunzer, centre looks like a Morse 2 taper but I’ve no idea how to get inside to change the bearing as they seem to be pressed together.
What make is the machine, and is it on a steel cabinet?
John

 

[Munroast]

You could, but the battery would be discharged - the charger connected would be charging, whilst the electrolysis was taking place. By itself, a modern charger will not output any voltage unless it first 'sees' a correct polarity voltage connected across it.

Would have to be very careful the plates didn't touch ! suppose I could bung a fuse in, would a 5 or 13 amp plug fuse do?

 

[Munroast]

Hand held reamers they are, but you can get a Jacobs chuck for your tailstock if it’s there which will hold them.
The rotating, or Lunzer, centre looks like a Morse 2 taper but I’ve no idea how to get inside to change the bearing as they seem to be pressed together.
What make is the machine, and is it on a steel cabinet?
John

yes it looks like morse2, looks like it would fit the woodworking lathe.

Machine is a welco lathe with milling machine, and it is on its own steel cabinet, its heavy, the specs suggest 35 stone! we dismantelled it as best we could and it still took three of us to lift the bed and motor off the cabinet

They look like reamers (hence the square shank ends - they are held in tap handles), so not milling tools at all. They are the one type tool you don't want to get rusty, or change the size of by using abrasives on them

hmmm, just been looking up what reamers do and the fact that they are all imperial probably means they won't be much use. Never mind I will still clean em up and put them on a shelf, if nothing else they will make my new engineering department look impressive - LOL

 

[Harry Bloomfield]

Would have to be very careful the plates didn't touch ! suppose I could bung a fuse in, would a 5 or 13 amp plug fuse do?

Good point! Either would do, but when I did it I used an old 12v car headlamp bulb in the feed. Then if it shorts, the lamp just lights up full bright, rather than blow a fuse.

The ground electrode needs to be as large as possible and to as near as possible surround the item all the way round - so a metal tank is best if possible.

 

[Harry Bloomfield]

hmmm, just been looking up what reamers do and the fact that they are all imperial probably means they won't be much use. Never mind I will still clean em up and put them on a shelf, if nothing else they will make my new engineering department look impressive - LOL

No experience of this, but I wonder if the reamers could be reground to metric sizes, should you need one?

 

[Munroast]

I had a go with the Live Centre. it worked well, better than I thought.
Got my hands on a traditional battery charger and think it was giving about 2 amps

Left it switched on for about 3 hours when I was out on the bike. The whole thing got fairly hot 40+ degrees. started to melt some of the plastic container!. And I got a hell of a fright when I disconnected it, quite a loud bang, (not as loud as a gun but that sort of sharp bang) I thing a spark when I removed the positive terminal must have ignited the hydrogen ?
thanks @JohnD for the idea

here is a before and after

the bearing is still to be pressed back in, obviously I didnt cook this bit

the bearing is an interesting configuration, two deep groove Ball Bearings with a thrust bearing between them, can't get the thrust bearing to turn, may be it just comes into action when under load? the outmost bearing is a little rough, don't fancy taking it to bits so might just leave it.

the outer bearings would have to rotate on the shaft for the thrust to work, but the outer bearings seem to be an interference fit on the shaft so would never turn - any ideas?

 

[Munroast]

@Harry Bloomfield
what are the two different scales on this battery charger. On the electrosi it started offat about 1.5 and went up to 3 on the bottomscale.

I know what watt amps is but why the diff readings ?
elf-rms & dc-arithm

 

[Burnerman]

I had a go with the Live Centre. it worked well, better than I thought.
Got my hands on a traditional battery charger and think it was giving about 2 amps

Left it switched on for about 3 hours when I was out on the bike. The whole thing got fairly hot 40+ degrees. started to melt some of the plastic container!. And I got a hell of a fright when I disconnected it, quite a loud bang, (not as loud as a gun but that sort of sharp bang) I thing a spark when I removed the positive terminal must have ignited the hydrogen ?
thanks @JohnD for the idea

here is a before and after

the bearing is still to be pressed back in, obviously I didnt cook this bit

the bearing is an interesting configuration, two deep groove Ball Bearings with a thrust bearing between them, can't get the thrust bearing to turn, may be it just comes into action when under load? the outmost bearing is a little rough, don't fancy taking it to bits so might just leave it.

the outer bearings would have to rotate on the shaft for the thrust to work, but the outer bearings seem to be an interference fit on the shaft so would never turn - any ideas?

That is a fabulous result!
I haven’t had one of these apart, but for sure an end thrust bearing would be needed.
John

 

[JohnD]

I had a go with the Live Centre. it worked well, better than I thought.
Got my hands on a traditional battery charger and think it was giving about 2 amps

Left it switched on for about 3 hours when I was out on the bike. The whole thing got fairly hot 40+ degrees. started to melt some of the plastic container!. And I got a hell of a fright when I disconnected it, quite a loud bang, (not as loud as a gun but that sort of sharp bang) I thing a spark when I removed the positive terminal must have ignited the hydrogen ?
thanks @JohnD for the idea

here is a before and after

Very clean result, and with no abrasion, you have not lost any detail.

You can polish it up with light oil or paraffin and a green scourer if you want

Next time, switch off the power at the wall before touching the connections, to avoid a spark.

It's possible to clean out cavities by inserting a probe, but it mustn't touch the workpiece

 

[Harry Bloomfield]

@Harry Bloomfield
what are the two different scales on this battery charger. On the electrosi it started offat about 1.5 and went up to 3 on the bottomscale.

Always disconnect at the source end first (battery and/or battery charger), to avoid sparks igniting the gas!

The two scales could either that the charger offers an high and low charge rate, or maybe two different battery charge voltages - 6v and 12v.

 

[StephenOak]

Surely the two scales are just the AC input and the DC output.

Because AC varies sinusoidally half the readings are negative, hence if you take the mean of the value you always get zero. So instead you square all the values (which makes all the negative values positive), take the mean then take the square root of that. Hence RMS for root of mean of squares.

For DC you just take the arithmetic mean.

My guess is that the elf is an old term for elv, extra low voltage, e.g.12V. Household 240V is low voltage in electrical speak. The 'push' that causes electricity to flow is known as electromotive force or emf , which is measured in volts.

 

[Harry Bloomfield]

Surely the two scales are just the AC input and the DC output.

On taking a second look at the photo, my guess was probably wrong, so your explanation would seem to be correct.

By AC input, I assume you mean output from the transformer and input to the rectifier? Why would anyone need or want to know that?

It is just the manufacturer, trying to make a simple battery charger look more clever and technical than it really is. Black paint on a dial is cheap.

 

[StephenOak]

By AC input, I assume you mean output from the transformer and input to the rectifier?

Yes.

Why would anyone need or want to know that?

Doesn't the load go down when the battery is nearly charged? If so this will show that.