I'm with the others. Smaller grommet, possibly cut the bottom end off and route it down from the top. Hopefully, the mast is stepped now? Another way to look at it though is to as another question.When routing control lines down and out of the mast, how big is the exit hole and are there allowances to increase sectional properties at the location? I don't know the answer to that, just throwing it out there. If you do have to drill, the best place to do so is in the middle of side which is the longest face, and as close to the bottom as practical. The middle puts it at what I is called the "neutral axis", assuming that the section is dependent on strength requirements not aerodynamics. There is not real stress at this location. Think of the trusses holding up the roof at Home Repot; all those "holes" created by rick-rack steel angles and they still support enormous loads. At the bottom of the mast, the material is mainly in compression so the bending stress approaches zero.
When I routed my wires up my mast, I strung foam marshmallows along the length, spaced about every foot or so. Now, even in quite a blow, there's nothing ringing down my mast, keeping me awake all night. Where they emerged from the mast, I milked the casing from a short length of StaSet over the cover, It helps with UV and abrasion and looks "wick'd pissah".
Well, I'll go back to dreaming of being close hauled while I stare out over a bleak landscape of 18" of snow, ice covered roads and frozen mud driveway. Think of me with pity if you sail.
Don
