Member postings for Howard Lewis

I have no wish to scare newbies, rather to help and encourage them.

But stean under pressure is dangerous. Get a scald from a kettle, at ambient pressure, and you will begin to understand.

If you have seen or heard of pressure vessel failures, you will be careful. (One of my colleagues lost the ends of fingers due to a failure! )

I am no H & S addict, far from it, but we all need to be safe.

Not warning someone, so that they are injured does them no favours, and damages the hobby.

By all means steam the engine, but first ensure that it is safe so to do.

The construction looks be excellent, so just make sure that time in storage has not reduced conditions to where there might be a danger.

It's the gung ho types who eventually finish up in A & E, (If they are lucky ) so don't condone or encourage that sort of behaviour..

Howard

Edited By Howard Lewis on 17/09/2023 16:13:50

Purely an aside, Try finding a Tap for 6.354 mm x 1.27 mm, or 0.907 mm pitch!

Or looking for 0.236 x 25.4 " one!

I'll settle for 1/4 BSW or UNF, or M6

If a machine was originbnally made to Imperial (Or Metric ) dimensions, best to stick to those units.

Yes, Ive come across some hybrids, 3/8 BSF at one end of a stud and 3/8 UNF at the other, or 5/16 BSF bolt with a 5/8 A/F head, but those wouldn't have beeen my choice.

Yes, we quote BA sizes in Imperial, but really are Metric (O BA is 6 x 1, with succeeding sizes decreasing by a factor 0.9 ) The odd ball feature is the 47.5 degree thread form,, but that might be the Thury parentage to differ from both Whitworth, and Metric form

Measuring items in units which were not used originally just makes for complications

Witness film speeds in Russian Gost units rather than Scheiner or ASA

DON'T mention Weston or Hurter and Driffield, or the A/F sizes for Whitworth form fasteners!

Howard

It looks like an American feeder that we have, so likely to be made to Imperial dimensions, rather than Metric dimension..

1/2 BSP is 0.825 (20.955 mm ) OD with a core of 0.734" (18.644 ) and is 14 tpi.

American pipe threads usually differ from BSP by 1 pitch, but in this case both are 14 tpi. but will be 60 degree rather than 55 degree Whit form.

So a wild guess suggests 1/2 NPS as close to your measurements (1/2 NPS is 0.840" (21.36 mm) OD, with a core diameter of 0.747 - 0.759" (18.97 - 19.23 mm  )

Howard

Edited By Howard Lewis on 17/09/2023 14:52:48

When a boiler is first tested by an inspector, it is hydraulicaly tested to 2 X working pressure, so a 120 psi gauge suggests 60 psi as the normal operating pressure.

Subsequent, usually annual, tests pressurise to 1.5 X W P.

The boiler inspector wil also check that the Safety Valve can release stean faster than the boiler can generate it.

Re safety.

A pressure vessel failure can be very injurious. A small boiler may not necessarily be a "widow maker", but it could be!

Even if the metal does not fragment with the danger of shrapnel flying about, the steam contain a LOT of energy.

At 60 psi, the steam temperature will be well above 100 C, probably nearer to something like 170 C.

For every gramme of steam that impinges on you, there will be 70 calories released as the steam cools from 170 to 100 C. But the real damage will the steam condensing to water; each gramme will release 536 calories, as it condenses to water at 100C.

So the quantity of heat released from Steam at 170 C hitting flesh at 37C will be about 670 calories PER gramme

And a gramme is a small unit of weight, so in reality, there would be a much greater weight of steam flying about.

That will be sufficient to strip skin!

So be VERY careful!

First job, in my book, would be a hydraulic test to 1.5 W P, probably 90 psi, (This will require various fittings to be renoved and blanked off ) followed by a steam test to 60 psi, to check the safety valve.

Howard

You have two unread PMs!

Howard

I was going to suggest boring out / reaming both pieces and then Loctiting in a piece of silver steel

Ah! Chicken and egg, you need the lathe operable to machine the two broken pieces!

Possibly someone from the Copventyry Club would help you by doing the boring /reaming?

Howard

Howi

F Y I

BT own EE, Talk Talk and Plus Net.

Just the packages on offer and prices that differ.

Strange that so many had problems after BT introduced an "upgrade"

Howard

I was involved with a 5" Raglan owned by a friend (Made a 4 way toolpost for it to mount on the compound slide )

Was very impressed by it. With a compl,ete set of changewheels and the QCG, it it was an extremely versatile machine. (Also had a set of collets, and a taper tuirning attachment.)

Wish that I'd known about such machines before buying my ML7. But it got me going to bring back memories from being an Apprtentice.

Howard

Since your lap top is new, you won't have the problem that we had when Talk Talk (alias BT ), without warning, withdrew support for Outlook on W7, leaving us without E mail.

Must have happened to lots of people, since it took three weeks to have the problem solved by going for a different E mail system.

Thankfully, the "fixer" managed to change over all E mails and address books.

Such is the price of what some regard as progress!

Howard

Does "P;lay with" mean restore, or actuallt use?

How old is "old"?

Drummonds could be over 100 years old, A Myford ML7 could be anything up to 75 years old.

A Myford ML1,2, 3 or 4 will be older than that.

Suitably set up quite useable machines, although, possibly withe exception of the ML7, accessories may be hard to find to equip the machine fully. ML7 geras are almost identical to those on the earlier MLs so can be modified very easily.

The problem might be obtaining Whitworth or BA form hardware. You might find yourself in the "Chicken and egg" situation of needing to get the machine operable to make what is needed!

Capscrews and grubscrews are the most likely to cause a problem. Hexagon nuts, bolts and setscrews should be fairly easy to make.

Some might regard a 20 or 30 year old machine, probably from the Orient, as old, but with so many being badge engineered, spares from other lool alikes, or even later machines, may be available.

Good work can be done on an old machine, once set up and operated, correctly.

OK, they may not be suitable for the high speeds to optimise carbide tips, but HSS is possibly superior to what was available when they first left the factory.

Howard

Over the years, plastic hose fittings have degraded and cracked. All have now been replaced by brass.

Proof that "Buy quality, buy once" is true

We now have a bag of redundant plastic hose fittings.

Maybe the O rings should be recovered, and the rest sent for recycling.

Howard

Supermarkets specify VERY closely to what levels a product should conform.

Even the number of blooms, and their diameter on a pot plant! (We were told this by a supplier of plants to a supermarket.) Consequently a computer controls the lighting and temperature of the greenhouse, to ensure compliance when the plants are taken for delivery.

So the supplier has to deliver a package whichn meets that specificatioin very closely, if they are to continue as a supplier..

Howard

To understand the set up better, read the thread on "Capacitor Selection".

The "Silly Old Duffer" post of 21:27 on 10/09/21023 shows very clearly the wiring circuit.

If you set the motor running, and then switch off, as it slows down you should hear a click.

This is the centrifugal switch remaking contact.

I am not an electrician, but my understanding is that when stationary, the centifugal switch makes contact, bringing the capacitor into circuit.

The start windings are then "live", but being fed via the capacitor, are out of phase with the main running windings.

This results in a torque which starts the rotor moving. As the motor speeds up, the centifugal switch opens taking the start windings out of circuit. The motor than runs on the "slip" between the magnetic field produced by the main eindings, and the field induced in the bars of the rotor.

In a motor that has seen use over a number of years, the capacitor could have failed, or the centifugal switch contacts may be burned and no longer making contact.

Replacing the capacitor (Note the comments about the voltage rating, it needs to be rated well above 250 volts ).

It is possible that no direct replacement centrifugal switch is available. If this is the case, either the existing one has to be repaired in some way (IF this is possible ) or a switch that is available, modified to fit. Again IF this is possible.

If you are unsure about what you are doing, involve someone who really does know\ what they are about.

You should be able to find a company that specialises in motor repairs, local to you.

When swarf got into the mmotor on my Myford, a local company managed to repair the damaged switch quite easily.

230 volts could prove fatal, or cause a fire.

Would it not be easier to make a new clamp nut with say six, tommy bar holes, as a means of speeding the "clamp / unclamp" operation, rather bthan having to make a riser block to get Centre height accrately?

Howard

Cou;ld you run 20:60 instead of 40:60? If you could, the chart on the cover would then deliver the pitches that you want, with the A - B - C settings as per the chart.

As already suggested, it might be that you have a Mk1 gearbox, so what you seek is half of what the set up delivers.

Howard

Post Codes are not infallible, even in towns, iur code covers more thanh one house, so a number is vital.

Out of town, a post code can cover several square miles; the more remote, the larger the area, it seems.

(On one occasion, having set a post code on the sat nav, told me that I had arrived at my destinatioon, on a long straight road with no building in sight for a couple of miles each way!

For six monbths, I worked as a parcels courier, and sometimes the adre3ss was so vague that havinbg traversed a road several times, the only solution was fo to radio the office abd get them to obtain specific details. Often Thye delivery address had been passed several times!

Howard

Hi John,

Welcome.

HUGE stocks of knowledge on here.

As Noel says if you have a query, just ask. One or more will provide a solution (Sometimes conflicting, it has to be said, but you then have a choice )

Howard

+1 for Noel's warning!

The TiN coating is there to reduce friction, as I understand it.

Have not been aware of any major problems on the TiN coated drills that have been sharpened on my Worden with pink grinding wheel. So Milling cutters wqould not seem to be a problem

HTH

Howard

Looks to be older than mine, which is 20+ years old, and a slightly different design.

But as long as it does what is needed!

The bracket for the intermediate pulley is cast iron and can crack if overtightened.. I put lerge washers under the bolt heads to spread the load more.

The RF25 appeared in many colour schemes for a variety of importers.

Rong Fu might even be able to supply the pulley, bearings and bracket, perhaps?

Howard