Member postings for Colin Whittaker

VFDs are (usually) used on induction motors. A single phase induction motor needs a phasing capacitor and a second set of windings. (O.K. a shaded pole motor doesn't but that only gets used on low power applications.) But you don't have a phasing capacitor!

So I think you have a universal motor with commutator and series field windings. A dimmer control should slow things down for you while generating significant RF interference in the locality for anyone still using an AM radio.

I guess you have a high speed wood saw.

Good luck, Colin

Who knows which is the number one greenhouse gas? Methane? Carbon Dioxide? No. It's water vapour and is responsible for around 30 degC of warming. Most of the earth would be uninhabitable without it.

You can therefore argue that burning hydrogen creates the greenhouse gas "water vapour". A truth, but an insignificant truth designed to persuade the scientifically challenged.

I'll get my hat.

I am still driving a TD27 in my 1960 Series 2 SWB land rover. There's no turbo to give problems. The oil is changed every 5000 kms. The air filter accidently lasted 100,000 kms and gave me a noticeable jump in power when I replaced it and adjusted the injection pump to just below the dark smoke on steep hills point. The water pump regularly fails every couple of years and gets replaced by a copy pump as no genuine pumps are available in this country. The amazing thing is the fuel consumption at around 15 km/l or almost 40 mpg! I wish the land rover Series 3 gearbox I'm using was as reliable.

And at almost 100,000 miles I'm still on the same exhaust system as when I bought it second hand although it has needed welding up now and again.

Edited By Colin Whittaker on 28/03/2023 02:12:50

An old school friend of mine, who is determinedly old school, hit a brick wall with telephone banking. When challenged with press 1 for yes and 2 for no he duly rotated the dial on his 1960s phone as instructed but without success!

On the plus side he'll soon have his bus pass and the time needed to physically visit the bank.

Continuity at fish plates. Not something I did today, but I remember (some 40+ years ago) that we used to drill the rail web (twice) by hand before inserting a wire and then hammering a plug in to secure and ensure continuity. But then the track engineers complained we were compromising their rail integrity and we had to switch to a hole less electrical welding/brazing technology.

I use a cheap 400W chinese grinder daily. This model works well for around 3+ years and then I switch to my spare and order a replacement. For coffee making I add some star anise to spice things up. For bread making I grind up flax speeds (not a job for a lightweight motor) and add to the dough.

There are cheaper and lower powered coffee grinders but I've found them to be a false economy.

Take care all.

While working as a standalone limited liability consultant for a few years (after retiring) I had to provide much of the above information on an annual basis despite my claims that nothing had changed from the previous years. The question that tickled me was the request for an organogram of the organisation for which I supplied a picture of yours truly with my job title (I think I was the director). In the end HSBC got too difficult about the US regulatory risk of banking my tiddly company and I became properly retired.

Before anyone says, "Ah but you need two directors for a company!" My company was registered in the Seychelles.

My Professor at University had a consulting company in the UK. His company was similarly small and so to fulfill the requirement for a second director he made his wife one. He said the requirement for the directors to meet at least once a year was generally performed in the bath with a bottle of wine.

My condolences to all the treasurers.

Well I tried, twice, but I couldn't make it work, or maybe I have been twice as generous as I intended.

How about? What about?

Whenever I see these two words I translate them to mean, OK I'm wrong but you have to prove you're not the same.

And the relevance of a historian to CO2's infra red absorption spectra is .......

Think Colin! Wise man and a fool. Mums the word.

My experience living in Thailand is that at low speeds the fans are very quiet until the bearings start to fail. And if you want to play with speed control you could try using a variable frequency inverter drive. But I think a larger diameter fan will probably be quieter and cheaper.

I liked Calvin's Dad's answer, **LINK**

If life imitates art ... then let's ban Hollywood's depiction of unrealistic gun battles where the good guys/girls always hit their target and never get worse than a scratch in return. Impractical? Nobody smokes on films anymore.

They could also mandate lifetime injury insurance for any new gun sale, even if the gun is lost or stolen the insurance provider is still liable.

By the way, having worked all over the world, including the scarier parts of the middle east, the only place I've ever heard a gun being fired was in the car park across the road from my downtown hotel in Houston, Texas.

Edited By Colin Whittaker on 20/07/2022 02:13:14

Edited By Colin Whittaker on 20/07/2022 02:13:42

In the large multinational company of field engineers I used to work for we used to have (about once per year) a 12V battery explode when jump starting, sometimes with fatal results.

Some of the explosions probably came from crossing the leads but others were correctly connected and still exploded presumably because of huge currents circulating between a fully charged battery and a fully discharged battery giving rise to hydrogen gas evolution ignited by a spark from a jumper lead breaking or making a connection.

The solution, which appeared on stickers in every vehicle, was to ensure that the last jumper lead to be connected and the first lead to be disconnected was to a chassis earth. Thus any sparks were hopefully distant enough from any source of hydrogen to keep things (relatively) safe.

I believe that in general the advice not to use the battery negative terminal for charging is just to reinforce best practice for the use of jumper leads.

Ketan,

Thought I'd let you know ...

My son finally chivvied me into stripping down the lathe and replacing the bearings.

The bearings were the sizes you advised.

After reassembling the lathe the headstock shake is reduced but still detectable. This seems to be because there is no way to adjust the preload. I'm now waiting for some bearing shims to arrive.

Thanks again for you assistance.

Colin

An archive that can't be viewed because of obsolete software to view.

No online editions of MEW and ME for months.

And now a reminder that my subscription is expiring!

I've taken that as a reminder to cancel my direct debits.

Ant ideas for a replacement home engineering subscription?

In sorrow, Colin

I can see copies of the Model Engineers' Workshop I'm missing on Pocket Mags but none here. Am I doing something wrong or has the MEW a new online home?

Thanks, Colin

sorry 20cm is 8" give or take, I asked for 8 inches.

Edited By Colin Whittaker on 09/04/2022 04:23:54

I went to my local wood shop in Phuket Thailand.

I'd like some 2cm thick planks says I. She pulls out a ruler squints and says OK 3/4 of an inch.

Right thinks I that makes my 20cm wide plank 6 inches. By 6 inches wide says I.

Out with the ruler again and she says that's 20cm.

I give her a funny look and say 2.5m long? Success!

It's a weird mish mash of length units out here. But the hard wood is very cheap and very pretty when stained/varnished.

Colin

Follow up from killing the noise ...

The black foam tiles arrived and were glued in place. Result? The noise got worse!

So with the help of my son I removed all the panels and finally gained a view of the compressor and its rubber shock mounting feet.

The one on the left is obviously the before and the one on the right the after. The after was purchased in Phuket town where a set of 3 cost approx. 2 GBP.

With three new feet the air conditioner is much quieter, probably as quiet as when it was installed 7 years ago.

Now, this is the tropics and the air conditioner has been working hard with a compressor that gets unpleasantly hot to the touch but does 7 years seem like a reasonable life for a rubber shock mounting? It is less than I would have expected.

An engineer told me before he died

as learned at the UK's foremost engineering university in the late 70's

Edited By Colin Whittaker on 24/02/2022 06:52:54