Peter,

I am assuming you have the IMF mainsail, yes?
I’ve never had one apart; but, I would expect there will be some mechanism and bearings under that plate associated with the IMF.  Is there any empty conduit inside an IMF mast to route wires & coax cable?  If there isn’t some sort of built in conduit inside the mast; then, this project is doomed before you even begin.  So, I would check the butt of the mast to see if there’s a conduit built in to the aluminum extrusion before doing anything at the masthead.

Roger Pihlaja
S/V Dynamic Equilibrium
1978. Sanford, MI

> On May 10, 2025, at 11:52 PM, peter beckerman via Rhodes22-list <rhodes22-list at rhodes22.org> wrote:
>
> Hi All,
>   I’m looking to add an antenna and an anchor light to the top of my mast. There’s a plate riveted to the mast top, and what looks like a little access hatch held on by three screws.  On mine two of the screws are rusted shut.  My question is:  what is this cover?  Can I just drill out the rivets holding the mast top plate and remove that along with the little cover?
>
> Thanks so much for your help
>
> Peter
>
> [ Sent From rhodes22.net ]
>
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