OEM Shroud Turnbuckles and Replacement Caps

[Fred]

My Cat28 MKii uses the (discontinued) OEM shroud turnbuckles as shown below. There is limited space inside the chrome sleeve. How are people preventing these from coming loose. Cotter pins (small)? Split rings (small)? Stainless wire? If they are being wired, is it sufficient just to install a stainless wire through the small holes in the threaded parts on the shroud and T-bolt?

Also... As I was missing several of the discontinued plastic caps on the cover sleeves, my enterprising, 15 year old, grandson has designed and 3D printed a dozen replacement parts for me. They are identical to the OEM part and appear to fit well so I'm excited to see how well they stand up to real-world use. The resin he used is UV curable so I expect that they should be resistant to degradation due to sunlight. The second picture below shows a sample of the 3D printed replacement part.

 

[Ward H]

After finding a couple of cotter rings laying on the deck due to having worked themselves loose, they are now banned from my boat.
I only use cotter pins on my rigging and life line turnbuckles.

Grandson did a great job on the sleeve ends.

 

[Calif. Ted]

Recently replaced mine for open turnbuckles, I could never get anything but pins to fit in them. I've had them for decades on 2 boats, they SEEM like a good idea but in practice, not so much. They were made by Garhauer, try calling them if you haven't, I used to get them direct from them. I just remembered I might have a couple old ones in spare parts.
I just picked the attached off their website, they have different sizes.
https://www.garhauermarine.com/shop...mast-boom-blocks-hardware/turnbuckle-tb-4bsc/

 

[Fred]

Recently replaced mine for open turnbuckles, I could never get anything but pins to fit in them. I've had them for decades on 2 boats, they SEEM like a good idea but in practice, not so much. They were made by Garhauer, try calling them if you haven't, I used to get them direct from them. I just remembered I might have a couple old ones in spare parts.
I just picked the attached off their website, they have different sizes.
https://www.garhauermarine.com/shop...mast-boom-blocks-hardware/turnbuckle-tb-4bsc/

Thanks! I spoke to Garhauer. They offered to custom make them for $15/set (plus shipping). I'm hoping that the 3D printed ones work out well.

 

[Fred]

The person at Garhauer insisted that the two sleeve caps in the “set” were different. I have carefully inspected all the caps on my boat and they all appear to be identical.