Member postings for Hopper

Yes, the Roman experience in Britain was in many ways much like the later European experience in Africa, as Conrad's narrator Marlow points out in the opening pages of Heart of Darkness:

Imagine the feelings of a commander of a fine—what d’ye call ’em?—trireme in the Mediterranean, ordered suddenly to the north; run overland across the Gauls in a hurry; put in charge of one of these craft the legionaries—a wonderful lot of handy men they must have been, too—used to build, apparently by the hundred, in a month or two, if we may believe what we read. Imagine him here—the very end of the world, a sea the colour of lead, a sky the colour of smoke, a kind of ship about as rigid as a concertina—and going up this river with stores, or orders, or what you like. Sand-banks, marshes, forests, savages,—precious little to eat fit for a civilized man, nothing but Thames water to drink. No Falernian wine here, no going ashore. Here and there a military camp lost in a wilderness, like a needle in a bundle of hay—cold, fog, tempests, disease, exile, and death—death skulking in the air, in the water, in the bush. They must have been dying like flies here. Oh, yes—he did it. Did it very well, too, no doubt, and without thinking much about it either, except afterwards to brag of what he had gone through in his time, perhaps. They were men enough to face the darkness. And perhaps he was cheered by keeping his eye on a chance of promotion to the fleet at Ravenna by and by, if he had good friends in Rome and survived the awful climate. Or think of a decent young citizen in a toga—perhaps too much dice, you know—coming out here in the train of some prefect, or tax-gatherer, or trader even, to mend his fortunes. Land in a swamp, march through the woods, and in some inland post feel the savagery, the utter savagery, had closed round him—all that mysterious life of the wilderness that stirs in the forest, in the jungles, in the hearts of wild men. There’s no initiation either into such mysteries. He has to live in the midst of the incomprehensible, which is also detestable. And it has a fascination, too, that goes to work upon him. The fascination of the abomination—you know, imagine the growing regrets, the longing to escape, the powerless disgust, the surrender, the hate.”

And if you want more "feel" when drilling from the tailstock, make or buy a small lever-operated sensitive drilling attachment that plugs into the existing tailstock taper. There will be an article and drawings to make one come up in MEW at some point in the not too distant future.

You are limited in the size of "window shakers" to about 3kW. If your workshop is larger, a larger split system might work better. I have a 7.2kW split air-conditioner in my fully insulated 2-car-plus-size tin shed workshop. Used for air con only but would not want to be any smaller in our tropical summers. Much quieter than a window shaker too.

Not with an induction hob, no. Propane torch, yes. (Stuck together thingies, not paint or glue!)

The original engines running on steam had the throttle on the supply line. Steam behaves differently from compressed air in an engine. Biggest difference is the latent heat in the steam that can be used to do work as pressure of the steam drops. From a more practical viewpoint, throttling the exhuast on steam might risk "hydraulicing" the piston in the cylinder with condensed steam that could not escape fast enough. Plus, throttling the supply of steam tended to "wire draw" it as it passed through the small opening in the throttling valve, which tended to help dry the steam out. As it maintained its original temperature (more or less) but left the throttling valve at a lower pressure, it was in fact somewhat superheated.

But for a display model run on air, connecting the governor to throttle the exhaust could be an interesting experiment.

Other uses? Are you able to make bits of steel glow red hot with one of these things?

The traditional way of controlling that spray of small brass chips off an HSS tool is to tear the side out of a cardboard fag packet, pierce a hole in it with a pen and then force it over the toolbit so it makes a small chip guard right next to the cutting tip. Works well.

It;s not the drinking of it that is a problem. It's the blindness and the brain damage that can follow. Ironically, the cure is to drink proper ethanol. It converts the formaldehyde that forms in the metho drinker's stomach into a less harmful chemical, or something. So the emergency room doctor told me on night shift at the hospital where I worked. In the absence of the hospital pharmacist to dispense pure ethanol at 4am, the good doctor had to give the miscreant a big slug of his own best scotch from his office. So we all sat around and had one, just to make sure old mate was OK.

Yes, as LBSC said, you can't scale nature, which would include time. Thinking about it some more, if a full sized engine doing 30rpm is viewed from a far distance so it looks the same size as a model viewed close up, it is still doing 30rpm. So model speed equals full size speed when it comes to rpm.

But linear speed not so much. The rim of the flywheel on the full sized engine will be doing many times the speed in feet per minute than the small model's flywheel rim at the same rpm. And I can't imagine a 5 or 7-1/2" loco doing 60mph and upwards around a typical club track. Its linear speed would seem to be reduced proportionately.

So presumeably, the model loco's axles and wheels could rotate at the same RPM as the full sized prototype, but the wheels being smaller in circumfrence transfer that same RPM into much less linear distance travelled, in the same amount of time. Time being not scalable as per LBSC..

So most videos I have seen of model stationary steam engines whizzing away like crazy on compressed air are in fact way over-revving. They should tick over slowly like the original big 'uns. But, who can resist the temptation to "see how fast she'll go"?

Edited By Hopper on 30/01/2023 04:11:59

Probably the most interesting swarf would be magnesium, when it catches fire.

It would be The Well-Beloved. One of his last, before Jude. So early 1890s.

Which raises the question: How does time and speed scale on a model? If you build a 1:12 model of a beam engine, should the RPM be 1/12th of the original's RPM? Or should it be 12 times the original RPM?

There is a listing for it on the dreaded Wikipedia with quite a bit of intormation: LINK There is a list of "further reading" at the end, including a book specifically about the Isle's several railways.

I love Hardy. Railway travel seems to feature in many of his novels. I guess he was writing at a time when the burgeoning railway network in the rural areas he wrote about meant a newfound affordable mobility for country people that previous generations had not enjoyed. Cutting edge stuff in its day.

EDIT: and there is this LINK

Edited By Hopper on 29/01/2023 10:19:03

Edited By Hopper on 29/01/2023 10:22:51

Or you could reduce the air pressure, or steam pressure as the case may be. A small cheap pressure regulator sold at hardware stores for regular air compressors will supply down to a few PSI, on which model engines will chuff over slowly quite happily. If running on steam from a small boiler, a throttling valve right at where the steam leaves the boiler works well. Dries the steam nicely too.

Or drill a hole and use a self tapping screw.

Very nice bit of work there. And a very handy attachment.

Sometimes you have to use the screwdriver and recharge it several times before it will take a full charge and operate the charge lights.

Usually the three charge light LEDs are one is red, one yellow, one green, indicating, flat, half charged and fully charged respectively. It can take overnight to get a full charge.

So try running the screwdriver and driving screws into a scrap of wood and out again to give the battery a good workout, then leave it on the charger overnight. You might have to do it several times.

Good luck tracking down Voche Pty Ltd. I am sure it is a faceless Chinese middleman company that markets products made by others and has no clue what it is marketing. The name sounds like it is a knock off of Bosch, one of the big names in electric screwdrivers. If it is like most other Chinese goods, the core element will be a standard unit, dressed differently by different companies. So if you search online for something like 3.6 volt screwdriver manual you might find one from another brand that applies to yours too.

I have had a similar go-around recently with a motorcycle voltage regulator from eBay. Made in China. Arrived with no instructions as to which coloured wire connects to which generator terminal and which is the voltage out to the battery and switch etc. Seller completely unable to comprehend the question let alone supply an answer. No idea at all. When I suggested they contact their supplier or technical advisors for intormation, their response was to offer to refund half the cost of purchase and let me keep the regulator. Which I did to avoud the nuisance of going to the post office to send it back. And I found instructions from another supplier online within a few key strokes!

Edited By Hopper on 28/01/2023 12:14:16

Tug, I think you are doing the right thing. There comes a point where these things are better to go to a new home with an enthusiastic new owner who will use them. I recently sold a little Honda 350 Four motorcycle that has been in the family since my late uncle bought it new in 1972. A hard decision to make, but it had been sitting unused in my shed for more than 10 years, slowly deteriorating, and getting in the way all the time. So now a younger bloke has it who is going to get it back to original nick and ride it in club runs etc. I think my old uncle would be happier to see someone using it rather than it just sitting doing nothing. I certainly am. (And I have room to do major projects in my workshop and a pocket full of cash to do it with!)

Thanks Dave, and sorry to hear about the oopsie with your car. I hate it when that happens. (Cost me $400 last time) Painting here is really weird. You can put stuff out in the sun where it gets so hot you can barely hold it with bare hands, but it still takes days for the paint to dry thanks to the high humidity. Even this stuff I ended up putting inside the workshop with the air-conditioner on to knock the humidity down. Then left it over night with no air con but with a fan blowing on it for air movement. Still took days. Small stuff, I have been known to put it in the oven at 150C for an hour or so. Seems to work ok but the paint does not stick to the job as well as when allowing it to dry at slower pace. Ditto hot air gun.

Good result. You can buy stepped pulleys on eBay in standard sizes that could probably be adapted to suit if you wanted.