Drilling a hole in mast compression post - yes or no?

[sr04]

I am trying to find a good route for my radar cable and wondered about using the compression post as an entry into the boat. I could drop the radome cable down the compression post as the mast was fitted and then run the cable along the bilge to the display unit. This would entail drilling a 3/4 inch hole somewhere near the bottom of the post. Is it safe to drill such a hole in the post?
Just seems preferable to a 3/4 inch hole in the deck and across roof linings through cupboards etc.

 

[jerryat]

Guess it depends on the diameter of the compression post. Drilling a hole that size in a 60 mm dia tube would be a lot riskier than one in say, of 100 mm dia.

Not an engineer, so hopefully someone will be along shortly to advise more professionally.

 

[oldsaltoz]

If the post is removed you can lay a stainless tube under it and fill in with Micro fibres and resin so no strength is lost, drilling a hole in base plate should effect it.

An alternative would be to drill the hole close to the base plate and get some more aluminum welded to support the hole.

Avagoodweekend......

 

[sr04]

Its about 3 1/2 inches square

 

[Norman_E]

Is it a wooden post, or steel? The real question is how do other wires from the masthead enter the boat, and can you use the same route?
The problem with routing wires from inside the mast via a hollow compression post is twofold. Firstly a hole through the mast support or entablature is a source of water ingress, as water often gets into masts, and needs to be able to escape onto the deck, not down into the boat via a cable hole. Secondly routing cables that way could give you a problem if you ever need to get at them. by sealing the hole in the entablature against water ingress you make it impossible to pull a cable out for inspection or replacement if it becomes chafed by the in mast halyards. Far better to run the cable out of the mast near the foot, then through the deck via a proper cable gland, or a swan neck fitting.