Member postings for Manofkent

I suppose you vould try a Centec 2B if one came up. Mine was certainly a single phase machine.

Could I make 2 other observations:

I eventually bought a 3 phase mill - a viceroy universal mill. Its a brilliant thing. Built like a tank. Originally I built a rotary phase converter with an old transformer, a motor and some capacitors to run it. This was as much easier than I had expected.

Nowadays I run it from a VMC. Just brilliant and so easy.

I also got a CNC mill eventually. I really wouldnt be without it now. Making a valve gear for my 3.1/2 gauge schools loco was so easy!

So my humble advice - give CNC and 3 ph a try. They have revolutionised my workshop.

All the best

John

I

Something similar happened on my Emco VMC cnc mill.

After days of checking the software and electronics it turned out one of the axis connections to the stepper motor pulley had worked loose. It was still engaging but intermittently.

Also had a similar problem once when the leadscrew nut became a little loose on the slide.

Both mechanical issues and relatively easily fixed.

Mach3 is excellent, but it only counts steps, not actual locations!

John

Starting the new year by recomissioning my Harrison toolkmakers lathe which has patiently sat in the workshop for the last 15 months.

It has what I think is a Bison 3 jaw chuck. It is 6" dia.

The chuck jaws have bolt on jaws, which are badly worn.

Ideally I would like to get new jaws, but new soft/hard jaws would also be an option.

The bison jaws (not the bolt ons) are stamped "3500".

Does this mean any jaws stamped 3500 will fit - ie does this refer to the scroll teeth and other dimensions?

Some suppliers seem to sell 3500/3200 jaws. Are these the same?

Sorry for the daft questions, but I do hope someone can just reassure me.

Many thanks and Happy New Year

John

I know some model engineers use Loctite 542 on water gauge fittings

If it is a cnc belt have a look at cnc4you webpages. There is a lot of info, they sell belts and pulleys.

John

I have the Boxford ACL which I think was the toolroom equivalent of the TCL.

I have converted it to Mach3.

It is a good, strong and accurate lathe, and mach3 is easy to use (machturn is the specific one for lathes).

There were no real issues with the conversion, just make sure you can override the position sensors when they are active otherwise you cant get the saddle/crosslide back into programmable positions!

John

This happens a lot on my lathe (an ml10 coincidentally).

The chuck has to be pretty well exactly aligned to screw on.

I put a squared blank in the tailstock, and gently hold this against the chuck jaws , then the chuck will screw on.

The blank is about 1" dia. I guess you could just use a flat bit of metal to the same effect.

Worth a try

John

I take the nipple off, and squirt oil in the pulley when using the back gear. I did start with grease, but the pulley got very hot. If it is a long job do it often, as Clive says.

John

Thanks Bill.

I had not heard of Horley. Great find.

John

Hi all.

Can anyone point me in the direction of a supplier for castings for the SR mogul loco Ashford in 5" gauge please.

Designed I think by Martin Evans - Reeves used to supply them but no longer list it.

Many thanks

John

I am reading this thread with great interest, although the maths is a bit over my head!

The OP does raise a good question - are we settling for model boiler designs that could be improved.

Many if our clubs are after all model and experimental engineers!

Thanks Steve. I will be setting my vfd up on my cnc lathe soon, and this is most helpful.

John

Nigel

Many thanks for all this information which is very helpful.

It reminded me that my Harrison L5 lathe (now long gone) was powered by a 1.1kw motor and was plenty powerful enough - so a 1.5 kw will give me power to spare.

Now I just have to work out how to fit the motor in the lathe...

Thanks once again

John

Hi Nigel.

My ACL is now a Mach3 lathe. But when I got it the internal wiring had been well messed up - I think it had had a swarf conveyor fitted at some time, and then removed without care!

I still use one relay per Z and X axis limit switch as in the original - and these wired in series.

Here is a picture of the Motor plate.

The Parker SSD drive has blown quite a few resistors and a capacitor - not for the first time either.

So I was wondering - I can gat a replacement for about £350, or go AC with a VFD as discussed above.

Any advice gratefully received.

John

Thanks for your helpful replies.

Nigel - yes it is a Boxford ACL - although the rest of the cnc is now Mach3 .

Steve - amazing YouTube clip. Thanks.

I use the lathe (and my cnc mill) for small runs of parts and for one off designs. Neither machine is worked on an industrial scale.

I tend to run the X and Y axis quite slowly - because I prefer it that way and feel a little more in control.

I recently had some blind holes to tap (M8) and a spindle speed of 150 rpm was comfortable, but could be a little faster I guess.

Nigel - the spindle motor is an SEM one and weighs a ton. The issue really is whether to repair the DC drive boards or start again. The motor itself is old but OK.

John

Thanks Old Mart.

So I looked at some suitable drives on the inverter drive supermarket (that's a great resource by the way - thanks).

A suitable Parker drive says it varies down to 0.5hz which would in theory be about 70 rpm. Is it right to assume the motor power would be pretty well degraded at that level?. I guess there would be other issues such as heat.

Has anyone run a motor at 200 rpm ish from a VFD? , and if so how was it.

Thanks

John

I have a large Boxford CNC lathe. The spindle is driven by a massive DC motor.

The motor is showing its age, and I am looking at upgrade options.

One option is to replace it with an AC motor and VFD - but I have no experience with VFDs.

I have 3 phase power available, so would only need the drive for speed control.

My question please - what range of viable motor speeds can I expect through a VFD please? What are your experiences?

For the technical I would probably use a 4 pole 2hp motor.

Many thanks

John

Jack

On my ML10 the leadscrew will continue to rotate when the dog clutch is disengaged, but can be stopped by hand if needed. It does not have the power to take a cut with the saddle - to do this needs the dog clutch engaged.

One tip - with the dog clutch engaged and saddle disengaged you can still move the saddle automatically by holding the saddle move handle. Useful when making short cuts.

John

Ian

I have the same AEW Viceroy mill in my workshop.

It is a Brilliant mill.

I have run it from a static converter. The one I used was a really old 5hp model a bit over the top but no harm done. It worked really well. A static converter generates 2 phases, and uses the mill motor to generate the third. You just have to be sure not to wire the control switches to the third phase as they won't work. I did this, but simply just swapped the wires from the converter until it did.

This arrangement worked fine on my mill.

Now I run it from a rotary converter. This is only because I now have a cnc lathe, and it needs proper 3 phases as it does not directly drive a 3 phase motor..

This powers both the mill and the lathe perfectly well and I built it myself.

Hope this helps.

John

Hi Weary

Of course we must keep 2 meters apart.

What I meant was that it only takes a lovely new loco to appear, or a technical problem with an engine, for willing hands to gather round and forget the 2 meter requirement!

This aspect can be hard to police.

John