Why are my conduit holes through the stern beam asymmetric?

It’s Australia Day, 222 years of our new culture in a very ancient land, and thank you to our old people who have looked after it for probably 200 times longer than that.

…and now, as I am feeling good, I have posed a couple of questions with this post.

I have finally worked out where the single best spot is located, to bring into the engine compartment, every control and source required for the engine’s operation. All these pipes and control cables will be individually chaff protected and will pass through a large conduit that itself passes through the stern beam. This reinforcing maintains the strength of the fore and aft webs and with the conduit ensures the buoyancy void within the beam.

Below – Routed trench through one laminate and core of the rear web part of the stern beam.

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Below two images – rebating the edge core of the future hole.

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Below – The finished rebating of the edge core.

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Below – Wet out of the balsa with a medium viscosity mix of silica, epoxy resin and a touch of micro-balloons.

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Below – 2 X 450mm of tapered 100mm x 1000gsm unidirectional glass wet out and rolled up into a rope.

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Below two images – inserting the glass “rope” into the circular trench.

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Below – The “rope” pushed out into the rebated edge, ensuring there are minimal voids.

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Below – A thick silica, epoxy and micro-balloons mix as an angled dam to hold the runny mixture and uni “rope” in place.

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Below – Two photos, one from each engine compartment looking at the back web.

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Below – Here, after curing, I used the same routing set to repeat the cut, this time, through the lower laminate. I was cutting away my template guide so had to be very careful at the end and leave a little, then sand with power file.

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Below – Close up of one reinforced hole just cut out. Two down, four more to go.

BTW apart from my title question, what is the diameter of the hole?

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