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Everything posted by Craig Sawyers
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The only thing I could mention is something I'm a bit anal about. The capacitor charging current from the bridge diodes is pulse like. The current drawn from the capacitors is pretty smooth. So it is always a good idea to isolate them in the tracking - in other words that the diodes connect individually to the capacitor terminals, and the output connections also connect separately to the capacitor terminals. Otherwise the pulsing current flow from the diodes flows in part of the output tracks and can introduce unnecessary PSU noise. Similar things can be done on the ground side as well to prevent the same pulsed currents from getting into the output grounds - this used to be called the "Calrec rectangle" after its adoption by the microphone company.
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Just length and number of teeth per inch. For fine dovetailing you want something with an 8" blade, filed rip tooth since cutting dovetails is a ripping rather than a cross-cutting operation; most cheapo saws bewilderingly come filed crosscut. For small stuff like jewellery boxes you really want 20 teeth per inch. For larger stuff like dresser drawers I'd go as high as 15 teeth per inch - but getting that started in the cut takes a bit of practice. The nicest handles are open or "pistol grip" rather than closed. Steer clear of the so-called "gents" saw, which has a round handle and has no good control as a result. There are several sources for really fine dovetail saws. I use Dovetail Saw - Pax Range from Thomas Flinn & Co Saw and Hand Tools Manufacturers Lie Nielsen are also good, and Rob Cosman has made his own (although it is punishingly expensive). I used the Cosman at a woodwork demo last year, and it really is stunning. Some saws are what is called "progressive pitch" where the teeth are very fine near the tip, and get coarser towards the handle to overcome the starting problem (Flinn Garlick and Lie Nielsen do these too). Rob's has two discrete pitches - 22tpi at the tip to get started and then 15tpi for the remainder. His theory is that you really want a coarse pitch to do the cut, since the faster you cut the more accurate it tends to be. Most fine makers ensure that there is only a few thou of set to the teeth - you want a minimum clearance just to prevent the blade from binding and no more. Too much set and the blade can wander in the cut. Then there is the entirely opposite approach of using a japanese style saw. These are used on the pull stroke and take a bit of practice to get used to. Super-fine kerf, so could be worth a bash for jewellery box joints. You want the Ikedame, which is the dovetail variety. A whole lot cheaper than traditional western pattern back saws. I use both types depending on the work. I also use the Hassunme crosscut and ripcut saws for cutting panels (although I last used them for trimming the bottom off our bedroom doors when we recently had a new carpet fitted!).
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My dentist is good at extractions - extracting money from my wallet in unholy amounts that is. Drives around in a huge BMW land cruiser and lives near Henley-on-Thames in a high-end village called Christmas Common.
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That is great news! Truly great news.
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Follow the method set out by Rob Cosman. Apart from being a fine hand tool craftsman, he has got blisteringly fast demos on YouTube doing a through dovetail joint in two minutes, and half lap dovetails in seven minutes. Google his name - you'll quickly get the drift. Buy his various DVD's - covers tuning and sharpening your dovetail back saw etc etc. Use his method of using hockey tape to bind your coping saw which gives it a whole lot better grip in your hand. With true deference to grawk, a dovetail jig gives really boring joints with wide roots to the tails. They have to be wide because of stength of the router bits. And you have yet another woodworking operation accompanied to the scream of a router. With a finely tuned saw you can produce tails limited only by the width of your saw kerf. I've got nowt against routers and power tools - I have two big and chunky deWalt half inch chuck ones and a lightweight Bosch, plus bandsaw and planer/thicknesser. But there is nothing more satisfying than doing a finely hand crafted dovetail or mortice and tenon joint without power tools. Because I'm a bit of a hand tool freak, I have an expanding collection of back saws. Most recent addition arrived today - a Diston apple wood handled dovetail back saw made sometime between 1896 and 1917 (from the rivet design). Once I joint it and resharpen it rip tooth it will be a fine and practical saw.
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To lighten things up a little - sheep have the same problem. The Australian sheep farmers have a term for Vicky's cat problem - they call the adherent material "dingle berries". Thinking of sheep, do a Tou Tube search for "Family Guy Sheep Shearing" for perhaps the most twisted take on shearing a sheep out there.
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So much trouble and sadness on the list at the moment. My heart goes out to all.
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You've got to be kidding me. Is yours a particularly hairy-butted breed?
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That figures, Reks
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It is a sobering fact that the only reason we are here is as a direct result that our forebears survived whatever life threw at them - famine, pestilence, persecution, war etc, going back over the centuries.
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Pretty much.
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I can't tell you how lucky I am that I did not understand a single word of why you lost 400 dollars. Flop, pushes, turn, rags, slow - it is fortunately complete gibberish to me. But the reason that I exist comes down to gambling. My grandfather was is WW1, and a great gambler on 3-card brag. On his way back to the front, he was on a winning streak and got back two days late. In the meantime, his company had gone over the top and was wiped out to a man - so Arthur was the sole survivor. Put on graves duty as punishement (ie recovering decomposing body parts from no-man's-land).
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The sort of neutral bored look of a bloke driving a car in a queue of traffic. Off camera, clearly.
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Did I mention that I saw James May in a traffic queue in our town recently (Abingdon UK)? A rather fine Rolls Royce, which is entirely consistent with May's penchant for Rollers.
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Totally beyond credibility. Experiment: I wired up a Fluke 8060A on ohms range with a Fluke 87V on micro-amps range. I could not get a reading on the 87V try as I might. The 8060A indicated a resistance in the mega-ohm range (1 to 10M), even pushing the tips into painful pointy contact with my fingers. I then took a 9V battery, and wired it via the 87V to my tongue (the traditional old fogey way of testing a 9V battery by feeling the tingle. Welcome to my world.). The tongue is about as wet and electrically conductive as it gets. I measure 12uA from a 9V battery on the tip of my tongue with the connections separated by a few millimetres. To get anything approaching the ten *milliamps* needed to give you heart problems would need you to stick a nail through the palm of each hand. I was not prepared to take the first steps in self crucifixion to test that out. But I could not get within three orders of magnitude of a problem current of that even on my tongue. So let's move on to the *real* problem of keeping you all breathing when dealing with dangerous voltages like 500V or 1000V - where the potential gradient across the skin can punch through and set up a real kick-ass current flow from a grunty power supply like the kgsshv one.
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Yeesh. Sounds a bit like a carbon dioxide TEA (Transverly Excited Atmospheric pressure) laser that I built back in the 70's. Machined all the bits myself, and it was a real lethal set up. The capacitor bank was two metal plates with screw clamps holding hockey puck HT ceramic capacitors. Around 10nF total at 20kV. 2 Joules storage and completely lethal - just out on the bench. Early 20's then and immortal, you realise. Found out about dielectric recovery the hard way. Discharged the bank, unscrewed it and put it on the bench. Ten minutes later, picked it up (in one hand, luckily) and it had partially recharged itself. Got a hell of a belt. After that I left a shorting link in place when it was not in use to prevent a recurrence.
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For sure. The stored energy in a car battery is huge, and its current capability huge - easily 400 to 1000A without breaking sweat when you start your car, each day, every day. The stored energy in a 60Ah battery is 60 x 3600 x 12 = 2.6MJ - about three hand grenade's worth. Hence my flippant comment on vapourising your head. But that does not mean that they are dangerous from an electrical shock point of view under normal circumstances. The skin-skin resistance is typically in the tens to hundreds of k-ohms, so currents from a 12V source are tiny and no problem. The internal resistance of the human body however is around 500 ohms (ie not counting the skin). So if you pierced the skin deeply on opposite hands with electrodes to get direct electrical access to the internal wet stuff, and connected them on a car battery you could in principle drive 24mA through your heart, which is enough to give you a really serious problem. You'd have to try pretty damned hard though, and have real determination to do this. And you'd deserve what you got. There are many and various ways to kill yourself with a car, but electrocution with the battery is not high on the list of causes of vehicular mortality. But a DMM? With <1mA output current? No way. A much surer way to exit this mortal coil is to lose track of where your hands are when working on an big and ugly electrostatic headphone amp. Or the internals of an old generation tubed Tektronix scope, or the inside of a tubed power amp for speakers....
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Agreed. If it were possibly to kill yourself with a 9V battery, there would be hazard warnings all over such batteries and they would come with shrouded terminals. Imagine the lethality of a 12V car battery! That would drive enough current through you to vapourise your head instantly
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Indeed - the combination of high DC voltage (around 1000V from + to - rails) and high current (many tens of mA) is quite lethal if between one hand and the opposite, or one hand to the opposite foot when the current runs across the chest. Across a single hand, say from palm to finger, it is bloody uncomfortable and gives quite a fright (experience of years of fiddling with tubed gear). So for anyone that is new to dealing with this sort of thing PLEASE read up (as suggested above) about the techniques of building and testing such gear safely, or at least non-lethally. And don't work on it when tired - that is when most dangerous errors happen.
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I just use regular dried yeast in my Panasonic. Works fine (provided the yeast is not too old; I had an old pack I tried to use up first off before buying new stuff). I can't make the extra large loaf size because it rises so much it hits the inside of the lid, so now only make the large size setting. I now get through a pack of yeast every two weeks - so now there is no expiry problem.
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Ha! You too, eh? Sort of think you only do once - the resulting stunted warty high density loaf was a true thing to behold.
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Deep enough to be a visual irritation. The damned domestic plant watering can had been put on the shelf (um - not by me) with the metal sprinkler rose sticking out. It was that that got me. Suppose I ought to be thankful that I was wearing specs - would sure have made a mess of my corneas.
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These to replace the ones you stood on? I put a scratch clear across my new pair yesterday, so I'm royally pissed off.