ZSpar mast sheave

[Mike O'Toole]

I just took down my Zspar mast for the first time in five years. Everything looked good except I found that the small sheave that the main halyard runs thru had not been turning for some time and the plastic material(actually Delrin)was worn thru clear to the 3/8'' SS pin. Am thinking about replacing the plastic part with a slightly larger aluminum sheave. Has anyone seen this problem and solved it this way? Thanks

 

[Bryce]

sheeve

had the problem on the main halyard sheeve on my 410. replaced it with a ball bearing model.BryceS/V spellbinderH410

 

[Steve Dion]

Bryce...

Bryce:I asked about doing that exact thing. I wanted to replace all the main halyard sheaves with bearing sheaves and two or three mfg. recommeded that I NOT do that. They said something to the effect that because of the type of loads that the halyard is under I was better off with a traditional one. Something about flattening of the bearings........How long have you had your bearing sheaves in place?

 

[Bryce]

Steve

This is our second season. the origianl one failed sometime the first season. We're stepping the mast this season, so I'll be able to get a good look at the sheeve while we're on the hard. Guess I'd feel that even if the bearing "flattened" it would need to be substantial before the sheeve stop turning at all. I think I'd rather have this than having the main halyard chaffing on a frozen traditional sheeve. The original sheeve failed in the same manner Mike's did. If there's a problem with the sheeve, when I get the mast down, I'll let you know.BryceS/V SpellbinderH410

 

[George Kornreich]

Had this also

I found the same thing... the delrin sheave flattened almost but not quite down to the hole. We removed this sheave, and my rigger felt that leaving it out was OK because the larger sheave just forward of that in the masthead is a high-load aliminum sheave. I'm not too happy about that, though, as the angle from the headboard of the mainsail to the sheave is not quite vertical... don't know if that's really a problem though. I visited US Spars in Alachua, Florida (the current vendor/distributer for Zspars in the US) to look at the construction of the masthead. Interesting... They said they never made a masthead with two sheaves. Well, I'm here to tell ya that indeed Two sheaves are present in many Hunters, to route the halyard into the proper alignment. You can get a replacement from them... use another aluminum one to replace the delrin sheave. Which I think I will eventually do.