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john B. john B. is offline
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Default Square holes in a round bar.

On Thu, 15 Mar 2012 23:52:55 -0400, Ed Huntress
wrote:

On Fri, 16 Mar 2012 10:41:45 +0700, John B.
wrote:

On Thu, 15 Mar 2012 13:43:35 -0500, Tim Wescott
wrote:

http://en.wikipedia.org/wiki/Schnuerle_porting



Set up a fixture to hold the cylinder liner at the angle you want the
port. Drill a hole to the largest diameter that fits your square port
and file to final shape.

If you are persnickety then leave the sleeve bore a few tenths
underside and lap of hone to final diameter after finish filing the
ports.


I'm thinking that he will have a file stroke length of around 6/10 of
an inch...


I don't think he mentioned the engine size but I've done essentially
that with .049, .15 and larger engines with out getting too many scars
on the opposite side of the bore :-)

With good sharp, clean, jewelry files 6/10" is a long stroke. :-)

--
Cheers,

John B.