Member postings for john halfpenny

Isn't that a coping saw frame - different animal entirely

Lots of older vans and large cars had LH threads on the UK nearside. Rolls Royce are brass, and easily stripped with an air gun, as favoured by tyre fitters. The general explanation is that rotational panting of a steel wheel centre applied a differential torque to the conical seat of the nut, which would unscrew a RH thread on the nearside; the larger the wheel, the greater the potential problem. Now we have spigot mountings with flat faced nuts, so no need for LH threads.

It can be bought mail order.

SOD , I interested to know how water is absorbed through a sealed cap -seriously.

As it happens, I used some 30 year old meths in a Mamod this week. It was slow to catch light, but raised steam ok. It was in a sealed plastic bottle, and I assumed some higher fractions had migrated, though the blue colour was fine.

Not easy because heat will also tend to expand and lengthen the spokes, which will tend to tighten the hub on the shaft. Quick heat on the hub, a bigger puller with more arms, and a big hammer.

Edited By john halfpenny on 06/03/2021 16:31:13

I think you are right Nigel.

I'm with Chris as well. In my apprenticeship I was taught the prejudices of my instructor and the approved methods of my employer (aka prejudices of the chief engineer). Most of these were excellent practices which I espouse to this day, but some held me back until I understood that other good and safe methods were available, even those which I would at one time decry as being dreadful short cuts and bound to lead to poor results.

Duncan's point is well made, though I hardly have need to move the flexible arm much. I've added an earth to the arm of my lamps.

Julian, being new to machine work, perhaps you don't realise that you can choose the relative speed of the power feed by selecting the appropriate pair of gears. Several combinations will work, and all are correct according to, for example, the material being machined and the depth of cut.

Here's the sewing machine lamp I mentioned above. Two for about £15.

LED sewing machine lamp, strong magnetic base and flexible arm. I've just bought two from ebay, and very pleased.

MIMS - the Monthly Index of Medical Specialities, if I recall correctly

One very cold morning I was instructed to hit the starter on an ancient double deck Leyland, and not release until told. The owner operator soaked rag in easy start, lit it with his fag, and threw it into the air intake. The engine clattered into life one cylinder at a time over nearly a minute. I was only then instructed to let go. A life lesson.

For those in the UK, Private Eye has a very sensible and widely praised commentary based on the science - unfortunately publication is only fortnightly. In retrospect it has been remarkably accurate, as well as effectively demolishing the various myths and political distortions.

Edited By john halfpenny on 15/02/2021 09:16:37

Thank you for your comments. I have a few things to think about.

I don't have any metric collets, and the cost of getting them for one chuck would seem to get a full set of ER. I also like the idea of holding round stock in the lathe, which has an MT3 spindle bore.

I couldn't find a clear direction from searching previous threads, so here goes. I have imperial Clarkson/MT3 and Osborn/R8 for my machines, which suit my collection of threaded cutters. I now expect to buy new cutters which will probably be plain shank metric. I am inclined to change to good quality ER metric, probably from ARC, with two new milling chucks, or perhaps just an MT3 with an R8 adapter for the mill. This will give me a wider range of gripping diameters, and I'll also add a couple of ER collets to suit my existing imperial cutters. I think ER will also give more versatility and allow me to use fixture blocks and the like.

Is there any good reason not to change, and to partially fund by selling the Clarkson and Osborn?

The suggestion of a Prius would be for electric power- assistance by way of a replacement steering column - we use Corsa or MGF in the UK for all sorts of classics. The LR will require a rebuilt steering box in any event, and I would stick with OE spec. There are plenty of classics that have had a box to rack conversion engineered, but this LR is not among them afaik.

Edited By john halfpenny on 31/01/2021 18:58:35

Stuart, you will also need to reposition the key which prevents the barrel rotating. Simply drill through the casting to the bore, and make a small hole on the opposite side to suit the key stub. The axial position is not critical, and you can see where I have plugged the hole with a button oiler. A second new oiler lubricates adjacent the handwheel, the originals being now redundant.