Here is a list of all the postings John MC has made in our forums. Click on a thread name to jump to the thread.
|Thread: Mot grace|
Woohoo I thought when the MOT news was announced, I won't need to get the motorbike MOT'd in May. Then reality kicked, MOT or not, when am I going to use it?
Interesting article in a newspaper recently that suggested the virus has been in the UK for a while, possibly since early January. Got me thinking about how many may have been ill already with C-19 without realising it, and now presumably immune?
Late February I felt a little unwell for a couple of days, lingering dry cough, basically the symptoms of C-19. Could I have already had it?
|Thread: What are you reading?|
Recently finished Sir Miles Thomas's biography, BOAC chairman along with many other jobs, a good read remembering that he has written it himself.
Now reading "John Wilkinson, King of the Ironmasters". Disappointing so far. Nothing to say why he was the "King of the Ironmasters". I'm hoping there will be some explanation later in the book otherwise its going to be a very dull read.
My local radio presenter was, frankly, boasting about his panic buying, 5 of this, 6 of that and so on. Then said most of it will sit in a cupboard, not used or eaten and get thrown away. That had me shouting at the radio!
What was nice though was a young couple who recently moved in to to a nearby house knocking on the door and letting us know if we needed any help in the C-19 crisis, give them a call. I, naturally, offered to reciprocate.
Brought back to earth by Mrs JohnMC, they must think you look old......
|Thread: Solar panel surprise|
I use an "Immersun", think thats how its spelt, to divert power to the immersion heater. Two attempts to get one that worked properly, couldn't set the time on the first one, otherwise its been good.
Tesla's Powerwall, is it worth it?
|Thread: Amadeal Lathe failed - customer service appalling!|
Worn out bearings straight out of the box? A friend bought one of those Clarke combo machines, same sort of problem. Not worn, it was brand new! Problem was adjustment, soon sorted, much easier than the hassle of returning it. The worse thing about this machine was the gearing to get the drive up in to the milling head, noisy, but my friend soon learned to live with it.
|Thread: Speedometer Ratios|
That looks like a chronometric rather than a magnetic instrument, could be wrong. Have a look at Gaggs speedo website, might help.
|Thread: Mystery forging|
Looks like an investment casting to me. Also looks like a Brompton hinge but looking at the picture of the unmachined hinge, they look like sand castings. As for material, my money is on malleable iron.
|Thread: 15/64x48 tap|
Metric? M6 x 0.5 possibly.
|Thread: What a sad day for the British motorcycle industry.|
It is a sad but inevitable that Norton should be finishing again. I think it was the most successful (long lasting?) attempt at resurrecting the name.
I say inevitable because what did the bikes have to offer at the selling price? Plenty of other bikes as good as and often better are available at considerably less cost.
No doubt the Administrators will sell the Norton name. Who will buy it? Seems to me that the name has become tainted by repeated and unsuccessful attempts to resurrect the brand.
I can see the new Brough Superior going the same way, if it does I hope its in an honest way.
Best wishes for the future to employees and customers who have been affected by this sad business.
|Thread: Noisy Lathe Gearbox|
No, its an oil rather than an additive. Just had a look at the Lucas Lube website, I see they no longer use the term "climbing oil", plenty more do, Plusco for instance.
Edited By John MC on 09/02/2020 08:00:05
Don't know if its been mentioned, try some "climbing gear oil" (google Lucas climbing gear oil, other brands available).
I first heard about this type of oil in relation to the new version of the not very good Morgan three wheeler. They have a gear box that turns the drive through 90 degrees. Its often very noisy, climbing oil turns down the volume, a bit, apparently.
|Thread: milling crankshaft on cnc mill using A axis|
During the early 2000's when I was involved in various aspects of engine design I visited a a crankshaft manufacturer in the UK midlands. They specialised in one off and very low volumes, the shafts were typically "car" size. I was surprised to see the method of machining.
The cranks were roughed out from a suitable diameter piece of steel on very heavily built lathes. No top slide, tool post mounted directly on the cross slide in the "front" position. The tool looked like a very substantial parting tool with a screw jack arrangement supporting the tip of the tool. Even with one machine in operation the building seemed to shudder every time the lathe took a cut. I found this very wearing, frankly glad to get out of the building after a few hours of constant noise and vibration!
The roughed out cranks were then transferred to 4 axis CNC machines that finished the cranks prior to heat treatment, grinding, radius rolling and peening/polishing. Watching the speed and ease at which the CNC's worked I asked why not rough out on the CNC as well? Apparently quicker to do it as they were, was the reply. I wonder if they still do.
|Thread: Nalon Viper|
Graham, never bothered with a tapered bore, I've always taken great care to get the bore (and piston) parallel in these small sizes. I think that the amount of taper required in these small cylinders with piston and cylinder made from the same (or very similar) metal is so small that it would be difficult to measure and I don't like the idea of guessing! I've always tried to arrange effective cooling of the cylinder to try and keep it parallel and round. Screwed on or "slip fit" fins doesn't do that.
Tug, I don't understand your point about preloading. Preloading of the bearings is to be avoided in this type of use, your design will, most definitely, preload the bearings when the engine warms up, assuming they are not when cold.
I hone both cylinder and piston using Delapena equipment, one photo show a small cylinder being honed while the other two photos show the external honing equipment, one is with the hone on a truing mandrel. To fit a piston (and contra piston) I turn a length of suitable bar to ~0,002" then hone to size, I make the contra piston quite tight compared with the piston. I've "rebored" many more cylinders for others than I've finished cylinders for myself!
Earlier on in this thread I commented the mounting of the crankshaft bearings being poor so I thought I would have a go at doing the job properly with the Nalon Viper, I've modified the "cooling system as well, the cylinder in the photo is for the Viper. Thats one of the engines I'm building, the other is another diesel of my own design, more or less, again with rolling element crankshaft bearing but with a different arrangement from what I have seen in many years.
Great to see the engine running Graham. I'm presently building two engines, close to completion now. One of them has had two pistons already, I use an external hone to finish a piston and neglected to true the hone before sizing the piston!
I do hope the OP is not thinking I'm suggesting that he is using pump diesel!
The reason I ask is that I'm wondering what the preferred fuel is, its been a while since I bought any. What with the demise of my local model shop, I'm not sure what to buy. to get my latest engine running.
What fuel are you using?
|Thread: Torx Grub Screws?|
The problem I have found with Torx is that the next size down (to the correct size) key almost fits, without care it can easily be mistaken for the correct size key. If the fastener isn't too tight it will undo. If its tight then rounds out the socket nicely. My local BMW motorcycle dealer hates them because of this, they are frequently asked to remove a damaged Torx fastener by owners who are unfamiliar with them.
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