On Fri, 27 Jul 2012 10:00:18 -0500
Pete Keillor wrote:

big snip
The broken cap screw has yet to yield.

You didn't say how big this is (diameter). If it is big enough I would
recommend drilling it progressively larger until you are in jeopardy of
hitting the threads. That is after giving up on the heat/penetrating
oil attempts. Then I would use a dremel or die grinder to open it up out
to the thread area in a couple places. Should be able to pick out
whatever is left at that point.

--
Leon Fisk
Grand Rapids MI/Zone 5b
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