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Hello from Spain, and question about mast ball and heel

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Javier
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Hello from Spain, and question about mast ball and heel

Post by Javier »

Hello fellow Sprint 15 sailors!
I'm Javier, I bought a second hand Dart 15 last September and sail in Torredembarra, a small town near Barcelona. I'm really happy to be a part of the Sprint/Dart 15 community, although we are one thousand kilometres apart!
I first lowered the mast the other day and noticed that between the ball and the foot of the mast (sorry for my lack of better words) there was a very small and shabby piece of what it looked like fabric. I have looked online about what it could be and learned that hobies have a teflon or plastic shim between the ball and the mast to reduce friction and I assume prevent wear.
In section 6 of the part list, it seems there is a stainless steel plate riveted to the mast heel (D00968) but I found none on my boat. The mast rotates quite easily as it is. Does the stainless steel plate act as a bearing for the mast like the Teflon discs in hobbies? In my humble opinion it would not seem ideal to have friction directly between metals.
Does anyone have any suggestion for this? Maybe buying some Teflon sheet and cutting a disc from it? I have no idea what thickness would work. Or getting the stainless steel plate? Again, it seems odd.
Thank you very much!
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Liam
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Re: Hello from Spain, and question about mast ball and heel

Post by Liam »

Welcome to the forum, Javier.

Our official supplier sells these:

https://www.windsport.co.uk/product/ss- ... -included/

The rivets are here: https://www.windsport.co.uk/product/4890/
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Brian Phipps
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Re: Hello from Spain, and question about mast ball and heel

Post by Brian Phipps »

the s/s plate sits on the top of a round s/s insert located in the top of the mast ball. the insert normally sits approx 1mm above the surface of the mast ball see picture of item 21005.
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WaveyDavey
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Re: Hello from Spain, and question about mast ball and heel

Post by WaveyDavey »

Hi Javier,

To expand a little on what's been said above:

A stainless steel plate (usually rectangular, some were round) should be fixed into the underside of the mast foot (usually by two rivets, some were glued). This plate bears the weight of the mast on to the stainless steel insert "bump" that should protrude 1mm or so from the top of the mast ball. This small contact surface between two very hard wearing metals creates a relatively low friction and long lasting pivot on which the mast can rotate.

If either of the stainless steel parts are badly worn down then they need to be replaced. The plate comes as a spare part on its own as Liam linked above. The mast ball I think only comes as a single item including the insert. I think I once heard of this insert falling out, but normally the insert is fine and only the plate inside the foot that needs replacing from time to time.

If the mast ball or mast foot castings themselves have become badly worn allowing a lot of front-back or side-side movement then its worth replacing them completely as this can hinder smooth mast rotation. Both the second hand Sprint 15s I purchased had this problem causing a loud clonk when powering up after each tack or gybe (a little movement and the occasional noise probably ok).

Links to the parts with pictures below. The part descriptions include details of the rivets you'll need. A good heavy duty rivet gun is essential.

Stainless Steel Plate:
https://www.windsport.co.uk/product/ss- ... -included/

Mast Ball (complete):
(Note: Rivet holes are not pre-drilled because not all boats have the rivets in exactly the same position. I made up a template from card to match the holes in my beam and used that to mark out and drill the mast ball)
https://www.windsport.co.uk/product/mas ... -included/

Mast Foot (complete):
https://www.windsport.co.uk/product/spr ... -included/
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Javier
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Re: Hello from Spain, and question about mast ball and heel

Post by Javier »

Hello David, Brian and Liam,
Thank you very much for your help! I checked again and there were no signs of rivets or holes, but there is a hard paste around the mast heel that is falling off in some places. The mast ball has the stainless steel protrusion and seems to be OK.
I think the mast heel came with the round plate and the hard paste might be old resin used to glue the insert, which also prevented me to see it clearly. Next time I have the chance I’ll clean the heel really well, and assess how much of the plate is still there.

Thank you very much!

Javier
edchris177
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Re: Hello from Spain, and question about mast ball and heel

Post by edchris177 »

Here’s what mine looked like, with original heel plate. It was an easy fix to replace it.
viewtopic.php?f=2&t=5909
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