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    60 degree Vee Twin 1.6cc

    It was discussed earlier about the pumping imbalance because the leading cylinder is already flowing before the trailing cylinder ports are open and that at this point the piston velocity is already near its highest. And that this was maybe offset with a small port on the leading cylinder. But...
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    Square holes ?

    Yup, just an application of solids of constant width.. Shapes and Solids of Constant Width - Numberphile: http://youtu.be/cUCSSJwO3GU How to Drill a Square Hole: http://youtu.be/L5AzbDJ7KYI
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    60 degree Vee Twin 1.6cc

    Some of what is said above is correct to the best of the ability to test but isn't the whole story. For one the calculation the delta in rpm cubed shows the change in power output is technically correct. This should be about the change in power exerted to the propeller. However this only proves...
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    Formula 1 RC 1/3 with V8 engine

    ahh, so you have made some alterations.. with the stroke and displacement up that much and by making the ports to match recommended flow speed then you avoided the things i was talking about. if it was 100% to scale you'd rev too high. this will be fun to see come together.
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    Formula 1 RC 1/3 with V8 engine

    gues i was mistaken. i didn't realize the stroke would be that short... seems whenever i see a cutaway of these things the rod look short and leaned over pretty hard but perhaps what i've seen hasn't been accurate or i've seen engines from another open wheel series and assumed it was f1.. 2.5:1...
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    Formula 1 RC 1/3 with V8 engine

    it's a scaled down engine that revs to 20,000 rpm in full size. the ports are gigantic. the biggest thing holdings it back will be valve stability and and timing events. put some ducati style desmodramics on that thing as and see how fast it turns... about the rod:stroke ratio, when it comes...
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    Formula 1 RC 1/3 with V8 engine

    if you map volume over time or volume to crank angle the only difference is rod:stroke. bore:stroke has zero effect on expansion volume vs crank angle. it's also note worthy that the difference rod:stroke makes is surprisingly small. 1.5:1 is very similar to 1.75:1 but when you push the extremes...
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    Formula 1 RC 1/3 with V8 engine

    one thing that happens with small scale is th rev range increases. Galileo was the first to notice the cube square law as it applied to animals but it applies to mechanical engineering. with 1/3 scale you may be increasing the rev range 3 times. your port area to cylinder volume ratios should...
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    Does longer lathe ways have any disadvantage

    there may be long term advantages to american or english machines such as long term parts availability. southbend still stocks some parts from when they got started and has all the old records to know what you need based on your serial number. but i'm sure a chinese lathe of decent size will...
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    Two cycle turbo diesel.

    those tuned pipes are upstream. even if that's what you meant a tuned pipe doesn't work like a common collector header on a 4 stroke that uses velocity and inertia and negative reflections from and increasing pipe diameter to scavenge the cylinder and help it blow down as much as possible, also...
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    60 degree Vee Twin 1.6cc

    agreed that closer angles have less risk of problems. the point of greatest volume under the pistons is when the crank pin is split between the two cylinders, so it's 45 degrees ahead of one cylinder and 45 degrees behind another. when you work it all out the pumping volume is the sine of an...
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    60 degree Vee Twin 1.6cc

    i may just have to build a 90* one with tuned pipes and maybe reed valves to show it can work... i wouldn't think it's the best compromise but there is no reason that it won't work. it may have more misses on one cyl that the other and not be great for a production engine at large scale but i...
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    60 degree Vee Twin 1.6cc

    the pumping loss is only 29.3% for a 90* twin but the phasing is all goofy, the truth though is the lower end pumping has more to do with start and idle than power, if you have a reed rather than timing everything and it can pass through the reed directly to the cylinder at the appropriate time...
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    Scraping and Honing

    yeah scraping works. you need a master flat though... if you have a good sized surface plate you can scrape all the flats you need to then go scrape the ways. aluminum will work but cast iron is mostly what the industry uses when they scrape. you can scrape some steels but steel can be very hard...
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    Machining CZ120 on a light CNC mill/router

    seems fast. i looked up sfpm for brass and i'm thinking 6-10,000 rpm and .5-1.0 cm/sec if i'm doing the metric conversions correctly.. i know engraving is usually done fast, but is that usually done with a 2 flute cutter? ofcoarse i'm looking at it like a milling operation so if th eengraving...
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    Where to find a large thick copper pipe & like sized Magnets?

    http://www.amazon.com/dp/B00123YGCC/?tag=skimlinks_replacement-20 as for metal, aluminum, brass and bronze will also work well. but depending on where you live it might be hard to find a piece of hollow round stock.
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    Can this motor be wired for 110v?

    that sounds like a perfectly reasonable price.. the running amps are probably less than the amps rating. that could be starting current or max load current. i'd hate to think an asyncronous induction motor is 50% efficient, and the actual machine load will ahve something to do with the actual...
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    Electric Motor Wiring?

    on other continents there is 50hz power.. they may also have different voltages. the voltage ratings are in 50hz and 60hz for different regions... the Y indicates star wiring where the coils are connected to a common point which is effectively neutral.. the D is the voltage rating when the...
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    Electric Motor Wiring?

    it doesn't have to be a vfd, but that's the best way to go,,, well most cost effective and versitile, anyway. a passive device may be more reliable. you can create a temporary third leg with a capacitor or inductor (inductors starters may be know as magnetic starters or static phase...
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    Can this motor be wired for 110v?

    absolutely, that is what regulates the speed, but that's unreleated to what i'm saying. hp is rpm*torque(in ft/lb)/5252... so if the power is equal and you half one factor the other must double. i understand that the power consumption and production depends on load and they don't constantly...
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