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I LOVE old aircraft and of course seeing a 1/6 scale P&W thread I had to open it. I lost about 40 minutes of sleep and it was worth every second! This is absolutely amazing Bill! Keep the pics coming
SnailPowered, proud to be a member of MetalworkingFun since Aug 2012.
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10-14-2012, 01:35 AM
(This post was last modified: 10-14-2012, 01:35 AM by bobm4360.)
Because of the connecting rod geometry, the cylinder with the master rod is the only one where the piston TDC is the same as crank TDC. The others lead or lag by a small amount. In P&W 14-cyl engines the master rods are in #6 and #9 cylinders, but ignition timing is set from #1 cylinder. At one time, compensated magnetos to correct ignition timing were optional, but the later engines did not have them. Compensated mags were only used on the 14-cyl engines, the R-1535 and R-1830 series.
Regards,
Bob
bobm4360, proud to be a member of MetalworkingFun since Jul 2012.
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That's it Bob
The big end of the master rod is the only one that follows the true circle of the crank.
The slave rod big ends have a elliptical path, so piston position per degree of crank angle varies.
Brian.
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10-14-2012, 08:13 AM
(This post was last modified: 10-14-2012, 08:14 AM by Highpower.)
(10-14-2012, 02:20 AM)Brian Wrote: The slave rod big ends have a elliptical path, so piston position per degree of crank angle varies.
Brian.
The things you learn on this forum are amazing.
It makes sense,
after the fact of course.
Thanks Brian!
Willie