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Sept. 30, 2006
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  • Separate Hydrogen and Oxygen from Water Through Electrolysis

    An interesting article - thank you - though the comments are possibly more entertaining albeit for the wrong reasons :)I would go along with suggestion of replacing the table salt with something else - and providing folks are careful, would suggest caustic soda while caustic (really?) is the best choice as other than sodium, it contains nothing more than oxygen and hydrogen.Unless it acts purely as a catalyst and just "hangs around", I am guessing that baking soda may be adding carbon in the form of CO2 to the gas produced.I may be wrong on that, but certainly sodium hydroxide will NOT contribute ANYTHING as a contaminate.As for the HHO generators, I find valid points on both sides, in the first case, clearly generating the gas from an engine>alternator>battery power source is not going to yield more energy that is consumed in making it - so really not a fuel, more an inefficient conversion of one type of chemical energy into another - BUT I do believe it MAY be beneficial particularly on older cars.The more out of sorts the engine is, the more I am guessing a whiff of something extremely volatile may be of benefit - even if the amount of gas added is totally insignificant from a "fuel" point of view, possibly it does assist in enabling a more efficient burn of the vapourised petrol. This could improve performance and economy while reducing emissions.In much the same way that OLDER engines often seem to do rather well on LPG though a more moder efficient engine doesn't seem to yield a similar benefit (in both cases of course, LPG has a lower BTU than petrol but in older cars, results often seem to be better than optimal - which is almost certainly down to the fact that the old engine was struggling to burn the petrol/gasoline air mixture as efficiently as it was suppoed to - the lpg however provided an "easy more efficient combustion".)So, I suspect an HHO generator may be of benefit on an older, tired engine with poor / fouled injectors etc or during VERY cold temperatures where the conventional fuel really is not being burned as well as it should be - the HHO gas may simply assist slightly in the volatility - as well as enabling the engine to run VERY slighlty leaner by adding a stochiometric mix to one which is normally kept rich. The more gas added, the closer to a stochiometric mixture, the leaner the burn. (I would expect a decrease in CO but an increase possibly in Nx ?)In much the same way, that TINY amounts of acetone in a new car seem to do NOTHING at all of use (as you might expect as it has a lower BTU than regulalr petrol (gasoline) - yet in an old car, can sometimes make for a cleaner burn - nothing magical I suspect other than simply lowering the flashpoint slightly and making the fuel marginally more volatile?Quite happy to be challenged on the above but you don't need to tell me how many reciepts you have for education (sorry, I mean degrees), just make a fair and reasoned point, I am keen to learn when I am wrong - but I have learned just as much from people who make "happy mistakes" and go "oh wow, that's interesting", than the people who aim never to make mistakes.

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  • guymark commented on Natalina's instructable Build a Soundproof Wall8 months ago
    Build a Soundproof Wall

    Helpful and it sounds (pun not intended) as though it worked rather well.I also found something out a long time ago when dividing up a downstairs sitting room into two smaller bedrooms. The original partition wall was nothing more than a 2' x 2' frame with plasterboard glued and screwed both sides and stuffed with loft insulation. It was quite possible to have a conversation from one room to the next without even raising the voice. In fairness I knew this was only the "start" but I was still disappointed at how badly it worked. It DID make a difference simply caulking around the edges though.With a limited budget but some re-thinking and the old carpet to remove I had the idea of using the old carpet to cover BOTH sides of the plasterboard wall. Mostly solvent based glue but some nails to hold things in place while the glue set.Already a MASSIVE reduction in audio.Next stage was to cover the carpet with strips of "tile batten" - I guess about 1" x ½" wood every 18 inches or so. Marks were made on ceiling, floor and walls to work out where the battening went. Battening fixed through carpet into original 2" x 2" frameNow, added final sheets of plasterboard each side by glueing and screwing to the batten and once again thoroughly sealing all edges with gloop (just used gripfill)Very cheap, fireproof (carpet sandwiched between non-flammable material) and very effective. LOUD TV in one room nothing more than a feint muffle in the other room.The partition wall is a sandwich of:-plasterboard:old carpet:plasterboard:rockwool:plasterboard, old carpet & plasterboard

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  • guymark commented on icinnamon's instructable Magnetic Stirrer w/ Hotplate for <$308 months ago
    Magnetic Stirrer w/ Hotplate for <$30

    The idea overall is a fair one but there are a few points which need to be mentioned, some already made by others.1. You need to connect the middle tag of the potentiometer (to either side) otherwise it will have no effect at all.2. Ideally, you might want to make (or buy, they are dirt cheap - £2 or so) a little motor controller from an auction site. The reason is that the motor will then have full torque even at very low revs. A potentiometer for this is not really ideal especially if the medium being stirred is perhaps a bit "thicker" than water - so requiring lower speed and full torque.3. Don't wire the LED in series with anything other than perhaps a 560 Ohm - to 1K resistor. Wired as shown will result in the LED becoming a DED (Dark emitting Diode).4. Don't use hot melt unless you will never be running more than about 50C - it softens quite easily. Araldite is not bad - and silicone is also resilient to high temp.5. For even a fairly modest peltier unit (that is at least big enough to be potentially useful), you are going to want at LEAST 5A at 9V. Personally I would suggest a motor, controller and power supply for 10A at 12V (fairly cheap on an auction site though certainly not $5)6. You need to heatsink the bottom of the peltier junction - otherwise within the space of a few seconds, the entire module will just keep getting hotter as it has no ability to "pump the heat away". A nice big heatsink is required - which then means a new layout is needed with regards tot he stirrer system.One possibility is to use four peltier junctions, each heatsinked and then have a small gap between them, such that the motor shaft can come up through the middle of them all. Either way, without a heatsink, this will not work for more than a few seconds on "cooling mode". Heating mode will work ok though as the entire assembly will just keep getting hotter.In short, a good idea but not one to construct yourself unless you can understand each of the points above. If you just construct "as shown" you will see a very brief flash from the LED and a stalled motor - or one barely running at all equivalent to slowest possible speed setting).So FAB idea for an instructible, but does need a little polishing to make it work.

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