I think you are right on all of these points. That said I would not use
dowel for the reasons others have mentioned. Epoxy encased wood slivers
would not rot and would make it easier to remove the screws if necessary. If
the hole is completely filled and the screw is centered in the epoxy you
should not need to worry about water getting in.
Using the wood slivers would make the drilling easier if the epoxy is
completely cured. As mentioned before I prefer to drill and insert the
screws when the epoxy is hard but not completely cured.

Graham Stewart
Agile, Rodes 22, 1976
Kingston Ontario

-----Original Message-----
From: Rhodes22-list [mailto:rhodes22-list-bounces at rhodes22.org] On Behalf Of
Chris on LBI
Sent: Tuesday, July 28, 2020 12:35 PM
To: rhodes22-list at rhodes22.org
Subject: Re: [Rhodes22-list] Repair of Spider Cracks at Mast Step Tabernacle

Great points that I had not considered (poor end grain holding ability and
end grain rot). I am a novice when it comes to this sort of boat
maintenance. The feedback raises a few questions for me. First question: If
the mast is stepped and un-stepped properly, it would seem that the force
acting on the screws should always be sheer force, not axial pull force,
right? Second question: Don't I want to make sure that absolutely no water
gets past the head of the screw and under the fiberglass to the core? I
presume that when a new boat is manufactured, the screws are sealed
sufficiently to prevent water infiltration to the wood core. Would the butyl
tape accomplish this? Should examination of the seal around these screws be
a routine part of a springtime inspection of the boat?



-----
Long Beach Island
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Sent from: http://rhodes-22.1065344.n5.nabble.com/