Member postings for Howard Lewis

Looks like if there is a need to show an image that was in one of the original Albums will need to be copied into the new Gallery.

But it will much simpler, if an image on a PC (or whatever ) can be copied and then pasted into a thread.

Or am I misundetrstanding what will happen in then hopefully nmear future?

Howard

Many record players were supplied with a multi sectored disc, so that the speed (33.3, 45 and 78 rpm ) could be checked and adjusted until at each speed the appropriate circle appeared to be stationary, evn under filament lamp illumination..

On motor vehicles the "Timing Light" is a strobe triggered by the ignition circuit so that the crank pulley appears to be stationary relative to the timing mark, allowing the ignition timing to be adjusted until the mark on the pulley coincided with the mark on the timing pointer. Early ones were neons, but the later mains powered Xenon one gave a much brighter light, making the job easier.

Howard

Strangely, I was recalling the dangers of using wood and aluminium on the same belt sander, when the letter from Canada appeared.

Even using for Steel and Aluminium can be dangerous.

Railways use Thermite, a mixture of finely divided Aluminiium and steel, as a means of welding rails together, because of the tremendous heat generated.

Steel wool will burn if a match is applied. The steel is sufficiently finely divided and there is pleanty of air to provide oxygen for combustion.

It would not be surprising to learn that Alumium swarf will burn quite readily.

Howard

In my experience, even on low ,pressure fluid systems, Banjo Bolts are bad news. There are four possible leakage paths, (One each side of the sealing washer ) whereas the swaged cup/cone system used on most hydraulic brake systems has only one per connection.

That is importanr when dewsaling with the pressures likely to be encountered in Hydraulic brakes.

In my book, such connections are safety critical.

Howard

So, after the changeover, all images, presently in Albums, (Having been copied / retained on our Pcs, etc ) will, need to be inserted into new Albums, if they are to be accessible to anyone wanting to view them?

Howard

Not being damilar with the Bridgeport, I would ,understand it to be as Willaim says, with the belts giving the speeds shown in each row

Since the speeds shown in High Range are double those shown in Low Range, that would seem to result from the speed of the motor doubling.

The plate could have been printed to make this more obvious..

But once certain that this is the arrangement, it should not take long to become accustomed to mikt, and operation of the machine.

Howard

If you are using a Slitting Saw, do NOT use a key.

If anything jams, the saw is likely to split and surround you with flying metal.

Luckily, I was not quite alongside when an Apprentice using a key (Disobeying instructions ) had his saw split. Half of the saw was still rotating on the arbor as the other pieces fell all around, and came down from the roof!

Howard

If you want to cut a gear, for a Myford, use a 20 DP cutter, 14.5 degree Pressure Angle.

Select the cutter for the tooth count that you need Theyb vare available from various sources, new or used.

They are usually marked with the tooth range and the depth of cut.

It seems brutal but you cut to full depth at one pass with a fine feed.

Not a particularly noisy process.

Well worth supporting the arbor with a tailstock

If you don't have a copy, Ivan Law's "Gears and Gear Cutting", No 17 in the Workshop Practice Series, will be great help.

Howard

In my experience Tap and Die Company are a reputable company, selling good material.

Don't think that they are a back street, "knock 'em out cheap" company. FAR from it.

They supply industry, with well known and respected brands, such as Totem.

If their products are good enough for Rolls Royce, they are good enough for me!

I have always been satisfied with the Taps, Dies and boxes bought from them. (I have BSW, BSF, UNF and ME40 boxes on the shelf ) and Perkins Heritage Group have bought from them.

Look at their website to see if they have what you want.

Did you ring the correct number, 020 - 8888 -1865? If amything, I have had problems ending the conversations!

According to the website, they open again at 0900 on Thursday 24th August.

Howard

Not everyone knows the maxim of "if all else fails, read the inmstructions"!

I know of a min lathe ruined by the user taking 3/8" cuts when the manual says that 0.010" for roughing.

WHAT did he expect from a 400 watt powered machine?

Personally, I think 0.010" is a bit cautious, but better safe than sorry.

Howard

Tim,

Almost certainly, we each have a stable containing at least one hobby horse that we ride from time to time.

I certainly have!

Howard

The machine that you select will be determined by several factors.

Space; Budget; and the use to which it will be put.

The budget does need to allow for purchase of things like a good vice, possibly other clamping equipment, tooling, (Cutters, Collet chuck & collets? ) possibly extra measuring equipment, and if you have any ideass of gear cutting, a Dividing Head or Rotary Table, with a matching Tailstock.

Where space is limited, it is not unknown for a milling machine to be placed across a corner of the workshop, so that the table effectively becomes the hypotenuse of a triangle.

In my case the final determining factor was Height.. To save space, on one end, the table handwheel has no handle.

Howard

I would have expected a drain connection to be a BSP thread, but with a machine of oriental origin, might be wrong.

Have you asked Warco?

Like many otheres, use an old deep baking tray under the lathe to catch a lot of the swarf..

Removing the rest from all the strange places that it finds is nore difficult, but and hand brush is useful, as are cheap paint or pastry brushes.

As said, wear heavy duty gloves when handling swarf, to avoid nasty cuts.

Howard

Strobe effects are very real.

Anyone who has used a strobe light will know that depending upon the frequency of the strobe, relative to to the rotating or vibrating item, it can appear to be moving forwards, stationary or moving backwards!.

We used to trigger the strobe with a signal generator, so that when the item appesared to be stationary, we knew the frequency at which it vibrated (often the rersonant frequency. We could then take steps to damp the vibration or to tune things so that the resonance was outside the normal running range. (Not always easy with low frequencies )

My shop has mixed illumination. Fluorescent on the ceiling, LEDs on the Mill, LED and Quartz Halogen on the lathe, and have never been aware of any strobe effects, but that may be because of the mixed lighting.

Certainly, before failing LEDS can flicker. I have put this down to failure of one half of the bridge rectifier circuit., so that it only strikes on one half of the cycle..

A smoothing capacitor will reduce the risk of flicker, as long as the lamp can stand the resulting peak voltage.

Probably just over 33 with a nominal 24 volt supply?

Howard.

Howard

Edited By Howard Lewis on 22/08/2023 08:05:11

Just measured mine. My kit was bought at least 30 years ago, so pre Bridgenorth days.

The plinth for the motor is 3" high

Width 4 15/16"

Lrength 6 15/16" with a 1" wide flange along each side, for the M6 setscrews that pass through into the tappings in the bars that reinforce the base

On mine, the capacitor was a shade too long to fit into the box, so the rear face had to be bored to let the plain end of the capacitor protrude.

HTH

Howard.

The usual clearance should be of the order of 0.002 - 0.003" (0.050-0.076 mm )

The parts should be cleasn, and free of oil or grease.

I used Loctite between the faces of a collet chuck and a fabricated backplate, to hold them oncve the nbtaper hadv been clocked trur and nthe bolts tightened.

When I wanted to separate them, to fit the chuck to a machined cast backplate., they could not be separted.

Really heavy blows with amallet would not shift them, so theyb remain together.

Howard

The Bug was used during the construction of the RHDR, a\nd was eventually rescued from under a pile of rubbish in a Belfast scrapyard.

Returned to Romney, she was restored ans is used occasionally for special trains.

Apparentlyn the LMS Black 5, with Stephenson va\lve gear was a successful loco, but never repeated.

GWR used Stepehenson gear on all its locos, inside the frames, opereating the valves for the outside cylinders, of four cylinder locos via rocking levers.

I think that in one or two instances the gear was set up with crossed rods, and called scissors gear.

Howard

With regard to mindsets, the most frustrating was one found when a Russion delegation came, wanting to sell to us.

I abandoned a meeting on injectors when every question was answered with "We will do whatever the central Committee tell us to do"

Iniciative factor, less than Zero.!

In contrast, our UK amd US suppliers would try anything to give the desired result.. The German supplier tended to stick more closely to procedures, but would eventually produce the desired result, having gone through procedures.

(One of their UK Engineers was told off for knocking on an office door and entering before being bidden so to do! )

Maybe it was just him, but a Polish American Engineer with whom I worked was keen on procedures and box ticking. To get something done in less than a week, going to the shop foreman concerned would often produce the desired result in 24 hours!

Almost of my working life was spent in problem solving, or diagnostics.

Yes, I think that the British are good at "Thinking outside the box", but not as good at putting things into production as the US.

Howard

Since the changewheels on non gearbox Myfords are 20DP, 14.5 PA, it would seem likely that the same would be used for gears on the QCGB models.

If you want to learn more about the calculations, Ivan law's "Gears and Gear Cutting", No 17 in the Workshop Practice Series will be worth reading.

From this you can calculate the OD, and PCD of each gear, which should confirm the cenre distance.

Howartd

CCMT0604 tips in a 6mm boring bar is the method used most of the time, once the hole has been roughed out with a drill. So shallow cuts , 0.005" (0.127mm ) or less

Often stop putting on the cut before finished size, and take spring cuts to creep up on redqauired size.

Can take several spring cuts before ik stops cutting.

Speed is about 500 rpm, with a 0.0025"/rev feed (0.0635mm /rev)

It can make a noise, but the finish is good.

All the above defies the usual advice for carbide tips, but ikt works for me.

If I have a reaner, I use that instead, rather than spending time on spring cuts.

Howard