AndyID

In Ireland a yellow line at the curb means no parking. Two yellow lines means no parking at all. Three yellow lines means no parking at all, at all.

If you are buying a kettle in a hard water area, always buy it on defurred terms. (Shamelessly pinched from "Around the Horn)

Yikes! I was speaking in jest about the value of my Bert Weedon's "Play In A Day" on Ebay. I found mine in the downstairs cupboard. Original price 4/6 (four shillings an sixpence). The copyright date is MCMLVII which, if I remember my Roman numerals correctly, is 1957. Someone on Ebay in the UK is asking 20.25 quid for one with the same cover artwork except it shows an original price of five bob.

Wasn't there a BR slogan about having it getting away for a day?

Better get my posterior in gear and get the place cleaned up. I'm picking Lorna up at the airport in four hours (takes an hour to get there). She's been gone for over a month, first in Scotland arranging a nursing home for her mum (now 94), then visiting our daughter in NJ. Aaarrrrgh! Where did I leave the hoover?

I wonder why they originally designed it with gears and coupling rods between the two inner axles? There was probably concern about all that torque ending up at one gear and stripping it. The coupling roads were likely an attempt to ensure that would not happen. Unfortunately, it also created a new set of problems. Despite the fact that the thing was a flop, it's actually a very clever concept.

I tried to warn you

If Lorna hasn't tossed it, I think I still have one of his books. Must be worth a fortune on Ebay by now.

I once shared a hotel lift in Birmingham with Kate Bush My uncle in Campbeltown had a smallholding that was adjacent to Paul McCartney's place. I think Uncle George talked to him a couple of times, but I'm pretty sure he had no idea who he was talking to! Pete, I think I noticed you are or were in NJ. We lived in Wyckoff. I worked in Montvale, and I could see President Nixon driving past my office. After that I commuted to a job in Manhattan - Train from Allendale to Hoboken, then PATH to the WTC. That was until the PATH station was demolished by a bomb in 93.

Sorry to hear that Stewart. Presumably it's one of those front loaders. Life in the US has a couple of advantages (along with many disadvantages) but one of the great things is that you can get a good old-fangled "top loader" washing machine. They are usually built like brick sheethouses, last for ever, and wash the clothes much faster than the front loader variety. Problem is most houses in the UK don't include a place to put something like that. Ironically the fashionable trend in the US is now to buy front loaders! The manufacturers claim they are "more efficient" and "use less water", but as they also cost considerably more I strongly suspect the marketing departments have much more to do with this than the engineering departments. The even funnier thing is that they sell expensive matching plinths to sit the things on so you don't need to bend down to load and empty them.

Two ladies meeting for coffee. One from Kelvinside, Glasgow, the other from Morningside, Edinburgh. Kelvinside Lady: "Och, our rates are just terrible! Do you have big rates in Morningside?" Morningside Lady: "Heavens no! There are no rates in Morningside. Maybe a few small maice, but no rates."

As long as the worms have the same "hand" and there are the same number of gears in both boxes, the boxes can face in either direction.

Many years ago my dad's Vauxhall blew its cylinder-head gasket while we were in northern France heading back to the Channel ferry. There wasn't much chance of getting it fixed quickly in France, so we limped back to Boulogne and caught a ferry to Dover. On arrival, my dad asked the customs officer for the name of the Vauxhall dealer in Dover. The officer told us it was "Seven Alters garage". Could we find the place? No! Eventually, we stopped and asked a local where it was. "Never heard of it" he said. "What kind of car is it? Oh, a Vauxhall! You want Southern Autos garage."

I should add that with the mechanical advantage with this mechanical arrangement, it's virtually impossible for the load to "back drive" the servo.

Yes, I completely agree. Have you tried increasing the rotation to achieve almost 180 degrees of rotation? It seems to work with the sample I have tried, but I'm not sure how consistent it will be. I'm concerned that I am pushing the servo electronics into rather non-linear response areas. It's certainly beyond the spec (such as it is!)

Hi Stubby, It's a bit difficult to explain why it will bind. Probably calls for a diagram, but I'll try it in words: Take the simplest case of four wheels with only one coupling rod on one side. All will be well as long as the axis of the rod is not in line with the axes of the axles (here be Vikings!). When the rod is in line with the axis of the axles (that's the same as the rod being half-way between its high and low travel) there is nothing to maintain the wheels at the same angle of rotation. In fact, it's actually possible for the wheels to start rotating in opposite directions! They won't rotate very far before they tend to lock up. Best, Andy EDIT: I forgot to mention that because the coupling rods are offset by 90 degrees (a quarter turn) one of them is always able to maintain the correct relationship between the axles even when the other one cannot.

If I understand correctly, you are considering coupling four wheels one side and not using a synchronizing gear? If so, I don't think that will work. You would have to couple all wheels on both sides to prevent the mechanism from locking.

Exactly. To a great many Americans, Gibson's portrayal of William Wallace in Braveheart is seen in just the same terms as Starwars movies. The real story may never be known, but I'm willing to bet it was very complicated.

As I am Scottish it's obvious that I am a close relative of Mel Gibson. The US is a very strange place. In many respects it is still locked in 19th century thinking. But I really don't want to turn this into a political thread.

I should have mentioned - please see my blog for information on using servos in a model railway environment.

Hi Simon, Yes it would work with a standard servos, although I thought the throw adjustment by adjusting the pulse widths was supposed to be a "feature" (don't tell anyone, but personally, I think it's just a PITA!) I had thought of putting the printed bits on Ebay (without the servo) as a sort of kit, but I'm not sure about the economics. The 3D printer is not terribly fast, and, like any machine, it needs a "minder", so I might end up having to charge far too much. Mass production might also be an option, but that means starting a real business, and I feel disinclined to try that again Then there's the shipping cost. I'm on US Pacific time. Do you have a 3D printer, or do you know anyone that does? I could send you the files and you could make the bits locally. The design still needs a little refining. I tried to use the screw supplied with the servo to attach the eccentric, but I'd like to see a longer screw there so I can beef-up the eccentric in that area and put a washer under the screw-head. Also, as I mentioned already, exactly how the banjo attaches to the piano-wire is a bit of a mystery, but that should not be hard to solve. Best A

But wouldn't that imply it has a circular aperture? This thing is elongated. (Not that it really matters! Banjo works for me )

Could be worse - you could be in North Dakota! We're not even in the same time-zone as Boise. Idaho is almost two different states. I find the weather here to be very agreeable. As you say, the Pacific moderates it a lot. We are at 2000 feet - it is warm enough to swim in the lake in the summer, but not so hot that we need A/C in the house. Winters are cold enough to produce just enough snow to make it beautiful, but not so much that it becomes a pain in the neck!

Hi Ian, We've had hardly any snow here (N. Idaho) too, and it's been quite mild. There seems to be a common misconception by some people in the UK (OK, OK, I said "some") that we live in the frozen northern wastelands. I'm less that 100 miles south of the border with Canada, but I'm at the same latitude as Zurich!

This is the version with 3D printed parts. The throw is adjusted by sliding the eccentric that sits in grooves on the top of the cam. I still need modify the thing the that looks like a tennis racquet so that I can attach a piece of piano wire to poke through the baseboard. The axis of the wire will intersect the fulcrum screw at the "handle" end. I should have used a tripod to take these pics, but I can't remember where I put it!