BWY stainless mast cap 26x

[TheLandlady]

Has anyone ever installed one of these stainless steel caps from blue water yachts on their ? I bought one thinking it was an obvious upgrade to put an anchor light on top, but I have been stumped trying to figure out the best way to drill holes in the tabs that also line up with holes I’d have to drill in the tip of the mast. I have a drill press I could use for the cap and could probably eye it up on the mast with a handheld, or even possibly set it up so the end of the mast points into the shop and sits on the press as well, but looking for tips and want it to be done right. Was thinking maybe I could mark the tab locations on the exterior (top) surface of the cap with a sharpie, then just tape it in place and drill mast and cap at the same time?

After I figure that out, what’s the best way to attach it? Rivets? Thru bolted? Tapped for machine screws?

[FittsFly]

I've possibly wanted to install mast light also someday. Could you post photo of mast cap? Might have some ideas for attachment

[OverEasy]

Hi TheLandLady!

Typically ne would temporarily mount in place (like with tape) then match drill in place and secure (with tapped holes for quality #10 hex head stainless steel machine screws & split lock washers) one tab at a time. (That way nothing shifts position between making holes)
- The hex head machine screws makes it easier to service in the future.
- The screw length should allow about 3 threads to be exposed in the interior side.
- The split lock washer will keep it in place but a drop of non-hardening Locktite is good too.
- Personally I’d avoid using any sheet metal screws or self tapping screws as they will have sharp edges and may fret or nick any electrical wires. Sheet metal screws tend to not hold or grip well over time or repeated use.
- Personally I’d also avoid the use of any “star” or “serrated” washers as they are ‘one-shot’ use items and tend to be much lower quality stainless steel which will tend to rust.

I wouldn’t worry too much about appearances as it’s gonna be 15 feet up in the air.
By far the vast majority of people will never ever notice …..
If someone ever does just give’em a good Bronx cheer for me!
Having a cap plate you put in place yer self will put ya head and shoulders above most folks!

Best Regards,
Over Easy

[Russ]

Stainless steel cap sounds nice. The 26M has this cheap plastic thingy that is very fragile. My anchor light is mounted on it, but I fear it can break off easily.

What about dissimilar metals? Is that an issue? Probably not as there are other SS hardware on the mast.

[OverEasy]

Hi Russ!

Yes you are correct. I mis-spoke.
Thank you for the reminder.

Stainless Steel with aluminum will develop galvanic corrosion with the aluminum eventually weakening.
The challenge is that when fastening to aluminum one has a limited field of choice…
Plain steel will corrode when in contact with aluminum as well… and leave rust stains.
Galvanized steel is marginally better and will rust as well if the coating is compromised.
Finding strong aluminum bolts is a real challenge.

To be honest the optimal solution would be to use aluminum pop rivets but one would need to drill the heads off and punch in through the core. Aluminum to aluminum is the ideal.

It’s the balance to deal with the practicalities where using a stainless steel is a functional solution.
Keeping the joint dry will minimize corrosion.
The top of the mast tends to be a relatively dry locale.

Here is a link to a prior post for a chart on dissimilar metals and corrosion potential.
https://macgregorsailors.com/forum/view ... ls#p364899


Best Regards,
Over Easy

[TheLandlady]

Hi TheLandLady!

Typically ne would temporarily mount in place (like with tape) then match drill in place and secure (with tapped holes for quality #10 hex head stainless steel machine screws & split lock washers) one tab at a time. (That way nothing shifts position between making holes)
- The hex head machine screws makes it easier to service in the future.
- The screw length should allow about 3 threads to be exposed in the interior side.
- The split lock washer will keep it in place but a drop of non-hardening Locktite is good too.
- Personally I’d avoid using any sheet metal screws or self tapping screws as they will have sharp edges and may fret or nick any electrical wires. Sheet metal screws tend to not hold or grip well over time or repeated use.
- Personally I’d also avoid the use of any “star” or “serrated” washers as they are ‘one-shot’ use items and tend to be much lower quality stainless steel which will tend to rust.

I wouldn’t worry too much about appearances as it’s gonna be 15 feet up in the air.
By far the vast majority of people will never ever notice …..
If someone ever does just give’em a good Bronx cheer for me!
Having a cap plate you put in place yer self will put ya head and shoulders above most folks!

Best Regards,
Over Easy

Thanks for the info, I was actually raising the mast today and took a look at the top from a ladder. It already has holes drilled for the chicken head retaining bolt that would fall exactly where the tabs on the ss cap would sit. I think I’d just need to remove the chicken head, tape the cap in place and mark the tabs thru the holes with an ink pen. Punch a starting point for the bit and clamp it in a vice and the drill press should have no problem. But, the mast is already up, so… next year! If I actually plan to spend the night on a hook this season, which I don’t really foresee, I’ll put a light up on the jib halyard, maybe Jerry rig some sort of Gaff or spar to hold it up above the top for 360° viewing. I found an old Davis 3300 with a cut wire for $20 at Bacon in Annapolis, which would be ideal for such a contraption I think.