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Rather than using my best guess I need help from a knowledgeable designer.
I'm building a 50 percent larger version of Elmer's #2 Twin Vertical Wobbler. This may not really be relevant to my question other than it made some math checking necessary to upscale the jig I'll be using.
The question is about the original dimensions used on the drill jig to locate the single port holes on the cylinders and the two holes on the adjacent side of the Column.
The top end of the jig is pushed against a (1/8) .125 pin used in the crankshaft hole, and the center line distance on the jig to the outer contact edge is (13/64) .2031. This adds up to a crank center line distance of .2656.
On Elmer's drawing of the crank disc the center line distance between the crank shaft and the crank pin is shown as (1/4) .250.
Is this .0656 discrepancy just a minor glitch caused by the use of fractions,? or is this over lapping scenario a necessary part of normal port design on oscillating cylinder engines,? Or is there a flaw in my math?
Sorry, that was three questions! ;D
-MB
I'm building a 50 percent larger version of Elmer's #2 Twin Vertical Wobbler. This may not really be relevant to my question other than it made some math checking necessary to upscale the jig I'll be using.
The question is about the original dimensions used on the drill jig to locate the single port holes on the cylinders and the two holes on the adjacent side of the Column.
The top end of the jig is pushed against a (1/8) .125 pin used in the crankshaft hole, and the center line distance on the jig to the outer contact edge is (13/64) .2031. This adds up to a crank center line distance of .2656.
On Elmer's drawing of the crank disc the center line distance between the crank shaft and the crank pin is shown as (1/4) .250.
Is this .0656 discrepancy just a minor glitch caused by the use of fractions,? or is this over lapping scenario a necessary part of normal port design on oscillating cylinder engines,? Or is there a flaw in my math?
Sorry, that was three questions! ;D
-MB