Seal penetrations in window frames

[skytte]

Hello!

I've removed the oil tank and rerouted some electrical wiring in the house, which is from the 1930s. For the oil tank, there was some kind of vent or similar that went out through a hole about 5 cm in diameter in the window frame of a basement window. They had also run electricity between the floors in the same way, i.e., through holes in the window frames...
Now I have removed this and want to seal these holes. How can I do this in the best way, and what material should I use to fill them in?
Thanks in advance

 

[oskis 123]

Assume it's wooden frames? If it were, I would try to make a piece corresponding to the hole in wood and glue it with polyurethane glue, I think. Make sure the fibers preferably run in the same direction as the frame. At least in the ends that are visible outward.