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Quote from: cnr6400 on November 10, 2020, 04:10:33 AMOne further thought - cutting studs from threaded rod and using scale nuts (smaller hex a/f size than normal machine screw nuts for a given thread) is usually far lower cost than buying hex head screws. Also more typical of what was used for fastenings on the real machines from 1865-1940 ish time period.I'm interested. Where do I find these? thanks
One further thought - cutting studs from threaded rod and using scale nuts (smaller hex a/f size than normal machine screw nuts for a given thread) is usually far lower cost than buying hex head screws. Also more typical of what was used for fastenings on the real machines from 1865-1940 ish time period.
As Chris mentioned, look for "small pattern" nuts. In the Micro Fasteners site, the link below (for stainless nuts) gives a choice between small pattern and regular machine screw nuts. https://www.microfasteners.com/home.php?cat=629Good luck on the shopping. Don't be shy about buying 100 nuts rather than trying to find just a few - you will be surprised how much hardware is used on models of old machinery. Chris Rueby will attest to that! Personally I think 6 or 8 studs and nuts on say a steam engine's steam chest cover looks MUCH better than just 4 studs and nuts, or philips head machine screws. (even though 4 fasteners will probably be strong enough and function OK. )
sounds like either a sticky spot in the revolution (if you turn it by hand can you feel the resistance change somewhere? ) or the timing of the valves is just a bit off, giving it a bit of a gallop as the piston on the near side in the video hits bottom. I like to connect just one cylinder at a time to air pressure and test, it can isolate where the issue is. Possible that one direction on one of the pistons is not getting pressure into it, or the exhaust is not opening soon enough.
Sounds like your shop elves stuffed a potoato in the exhaust pipe then! I had an engine where I had it all assembled, would not run right, then on taking it apart found that one gasket had no hole in the center!