Shamrock 30 mast corrosion

[Stu_shamrock]

Hi all,

I just bought a 1976 golden shamrock 30. The mast has seen better days; it has already been sleeved, and has pretty bad corrosion at the step.

I’m planning to replace it, but struggling to identify the correct size and profile. Happy to use a more modern profile but want to make sure it’s correctly spec’d for the boat. I traced half (see pic below), oval and approximately 165x110mm. The length measurement is accurate, but the width could be 110-120 as I just flipped over the half tracing to complete the picture… I read somewhere online that this boat came with a kemp mast, but not sure if this is correct or not. Also the mast step looks kind of odd - was this standard for Shamrock’s or a dodgy fix because the mast was cut?

Any help much appreciated in

1) identifying which mast I have,
2) which modern profile / manufacturer can I replace it with?
3) mast step is standard or because of cut mast?

thanks,

Stuart

[Stu_shamrock]

And here’s the traced profile. 165x110 approx dimensions. Any guess which manufacturer?

[Dsanduril]

Here is a Kemp document that lists their spar sections (second page):

https://moodyowners.org/wp/princess-...5130422014.pdf

Looks like they have a 170/115 that might be your section?

If that doesn't work go through each spar manufacturer at the RigRite site and check against their sections (it can be a fair amount of legwork).

https://rigrite.com/A-Main/spar_M.ph...Spar%20Section

[Stu_shamrock]

Originally Posted by Dsanduril

Here is a Kemp document that lists their spar sections (second page):

https://moodyowners.org/wp/princess-...5130422014.pdf

Looks like they have a 170/115 that might be your section?

If that doesn't work go through each spar manufacturer at the RigRite site and check against their sections (it can be a fair amount of legwork).

https://rigrite.com/A-Main/spar_M.ph...Spar%20Section

Hi Dsanduril,

Yes the 170/115 is close. I’m confident the 165 length measurement is accurate, so I trawled through all the manufactuer mast profiiles on rigrite and found an oval shaped Kenyon cruising mast profile 4365 (see pic below) that is also close, 6.5” x 4..3”. Not sure though if Kenyon would have been a possible / likely supplier choice for a Shamrock in 1976(?).

So, I guess now I’m just trying to get the correct specs for the original mast, in order to choose a modern new replacement.

Any ideas where I might also look for a used mast & boom, say 5 years old that would be correctly spec’s for the boat?

[Spot]

Stu, all the best for finding a new or used mast.
It's hard to measure a shape like that. You could try some cardboard templates or blowing up a photocopy of the section to full scale and making a cutout to test fit.
Fitting the existing sail slugs, goosenecks, and other old mast hardware seems important unless those are on the chopping block too. I think the Selden and Kemp you mentioned are the same slugs.
Are you going to return the mast foot/base to something more standard?

[Stu_shamrock]

Originally Posted by Spot

Stu, all the best for finding a new or used mast.
It's hard to measure a shape like that. You could try some cardboard templates or blowing up a photocopy of the section to full scale and making a cutout to test fit.
Fitting the existing sail slugs, goosenecks, and other old mast hardware seems important unless those are on the chopping block too. I think the Selden and Kemp you mentioned are the same slugs.
Are you going to return the mast foot/base to something more standard?

Hi Spot, I’ve since seen a pic of another Golden Shamrock with the same weird step, so I guess it’s standard from the factory.

If it doesn’t break the bank, I’m happy to change out the gooseneck and slides etc - it’s all pretty ancient. Just want to make sure that I get the correct replacement for the mast. Would also like to replace all the standing rigging with dyneema (except the forestay for the furler)