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Help Support HMEM:

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    Electronic glo-plug ignition?

    Elektor electronics magazine had a special glow plug regulator that could deal with "flooded" glow plugs. Just a simple circuit with a power transistor and op-amp that monitored the PTC characteristics of the glow plug. It was powered by the 12v battery of the starter box.
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    4 cylinder/4 stroke mystery engine

    For 20cc 4 cylinder a small 5 cc engine carburetor should be enough. You only draw 1 cylinder at a time
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    Chrysler Hemi 1/4 scale

    I think that is used to calculate compression ratio by measuring the chamber's volume.
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    Stanley Style Steamer

    Check this out. The boiler is at the end
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    What the heck?

    I run 50 Hz 4 pole motors to 120 Hz all the time. 3~ 230 motors can be run with a 400 V VFD with the correct parameters. The power will increase linearly up to 86.6 Hz when the motor is supplied with 400 V and then stay constant until 120 Hz. Never had a problem this way with motors up to 2,2...
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    Oil sight glass

    You can make 2 small rectangular frames in thin aluminium, 4 holes in the corners and sandwich a rectangular window in polycarbonate. On the case yoy need 4 threaded holes to screw on the aluminium/ polycarbonate/ aluminium sandwich and a hole for the oil to get through on the bottom and the...
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    Popular Mechanics 1963 engine

    The little engine has a nice sound. A small capacitor will stop the flickering of the led but something about the sound and flicker makes it look cool👍
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    Popular Mechanics 1963 engine

    At $3,25 a month rate in 1959, you can't complain what they charge nowadays for broadband:D
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    Popular Mechanics 1963 engine

    Thanks. This one is not at the regular PM archive. Just found a neat metal bender for the shop in page 171👍
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    Popular Mechanics 1963 engine

    Funny, I thought the same thing. I've read many copies of the PM magazine of the time but I can't find the May 1964 issue online. This is the month I was born.
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    O-ring for piston ring

    You could try a X ring
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    tube pump

    A small planetary style speed reducer will enhance the visual effect and will insure the pump works correctly at a slower speed.
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    Used Computer Hard Drive Parts

    Every now and then, some sensitive data devices are destroyed in one of our shredders at our recycling plant. They come with some security guys and film and wait until everything comes out in little pieces. This is not very good for the smaller shredders because the pieces of magnets stick...
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    Used Computer Hard Drive Parts

    To remove the magnets, I clamp the assembly in the vise with one jaw on side of the magnet (facing down) and the other on the plate and tighten slowly. It usually slides off. There are usually 2 little dimples on the holding plate to center the magnet.
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    A 220v question

    Old washing machine programmers used small synchronous motors with this problem. There one way is just a small spring wound around the shaft with one end tied up. If the shaft rolls in the wrong direction the spring tightens and blocks the shaft.
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    Arduino Rotary Table for Dummies

    To program a quick stop, you can use the button press to change the "target" value to the current running value adding some extra steps to cope with safe deceleration. In this way, you can stop without losing position.
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    tachometer, the easy way

    For a quick rpm sensor you can use a small dc motor as generator. A potenciometer to calibrate and a voltmeter is all you need. Dc motors generate a voltage proportional to speed
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    Steam Engine Factory Layout

    Nice engine. I can't see clear but it seems that the crank should be offset by 90º and not by 180º to start without help.
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    Cutting an outer ring.

    The direct translation for the Portuguese word broca craneana "hole saw" is skull saw. :D
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    Pressure gauge??

    It's still a pressure gauge indicating atmospheric pressure at the moment :p