How do you replace turning blocks at the mast base

[All U Get]

Here is a pictures of my Z-Spars Mast Base. Some of the blocks had been replaced at that date, the rest since. Note in the photo from the aft end the slot under the plate. That's where the nut slips in and is captured so when you thread the stud in, it can tighten properly. There is one of those slots in line with each stud hole.

Back on topic. I don't want to remove a stud and then not be able to get the new stud/block to thread back into the nut. I broke one of the blocks. As a temporary fix, I ground off the pin in the stud and attached a replacement block with a shackle and pin (that is the one with the cotter pin in it). Has anyone actually replaced one of these in place without pulling the mast and mast base? I'm not interested in discussing the pros and cons of various block, but want to know how to replace the block without getting myself in a position where I can't get the stud back in or end up twisting off the stud.[/QUOTE]

I'm proud of you man. If all these engineers can build stuff we can't break sailing would be more fun (ie. make stuff removable). All those blocks look like Medusa so I'd use a mirror when working around it. If you need a small grinder with a metal wheel I should be down that way in a few months.

All U Get

 

[smokey73]

I've got a Dremel and it works great. That is how I cut off the stud pin on the one I replaced. Thanks anyway though. Where are you coming down from?

 

[JRacer]

Thanks Racer. That's the info I needed! Thanks to all the others who commented too. This site is always my "go to" place for advice and info. Sorry if I was a little "short" on my earlier response but its still good to get opinions on what might be upgrades that I can consider when I'm doing work. I think I'll stick with the original block style if I can find them. I've got a temporary fix in place and will order the new blocks.

Put a call in to US Spars. I've found their rigger, Matthias Klemm, to be very helpful on issues with upgrading parts on my rigging. I'm sure they can get you the right replacements.

 

[All U Get]

I've got a Dremel and it works great. That is how I cut off the stud pin on the one I replaced. Thanks anyway though. Where are you coming down from?

Sailing from Maine if the storms go away.

All U Get

 

[kloudie1]

I would be tempted to only replace the sheave itself.. by grinding one end off the axel pin and removing it then carefully measure the sheave wheel and buy a new proper sized stainless bolt/locknut for the axel. Buy several to replace the others..
https://shop.sailboatowners.com/search.php?brand=sailboat&kw=Sheave

 

[smokey73]

I would be tempted to only replace the sheave itself.. by grinding one end off the axel pin and removing it then carefully measure the sheave wheel and buy a new proper sized stainless bolt/locknut for the axel. Buy several to replace the others..
https://shop.sailboatowners.com/search.php?brand=sailboat&kw=Sheave

I'm looking at that option too.

 

[Ron20324]

I wondered where those blocks came from....
I had been looking for a block like that with a threaded stud, and couldn't find a source.
.

They are 36$ on the B parts site.