Plain bearing vs ball bearing blocks

pcoe

New member
39
1
Virginia
I am in the process of replacing my old blocks with new along with new lines. 

All my old blocks appear to be plain bearing type. I read that you should not change out all your blocks with ball bearings or roller bearings blocks, as they tend to potentially flatten the ball or roller under high static loads. I am not sure if this is accurate or would anyone notice over time.

But if it is, does that mean that your halyard mast base blocks would need to be plain bearing type and mainsheet and boom vang should be ball bearing blocks?

Outhaul and cunningham plain blocks? 

Any thoughts?

 

Zonker

Super Anarchist
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It is true. 

Mast halyard blocks - plain bearing

Mainsheet - roller/ball

Vang - I'd say unless you play it a lot, plain bearing. They tend to be loaded up and left alone for some time

Same with outhaul/cunningham. Really depends on how much tweaking you do.

And also size of boat matters too. Bigger boats tend to start to get more plain bearing blocks except the really racy ones.

 

SloopJonB

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Every ball bearing application I've had on my boats has been a pain in the ass for no discernible benefit except traveller cars.

The latest is a bunch of Harken cam cleats - jillions of tiny little balls in 4 layers on the cam pivots, lots of which had flattened or crumbled.

And for what? If ever there was a place for a plain bearing that's it.

I would avoid them wherever possible.

 

Parma

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Wait a minute! You mean there is a difference between blocks??!! When did that happen?!

 

Mark K

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I am in the process of replacing my old blocks with new along with new lines. 

All my old blocks appear to be plain bearing type. I read that you should not change out all your blocks with ball bearings or roller bearings blocks, as they tend to potentially flatten the ball or roller under high static loads. I am not sure if this is accurate or would anyone notice over time.

But if it is, does that mean that your halyard mast base blocks would need to be plain bearing type and mainsheet and boom vang should be ball bearing blocks?

Outhaul and cunningham plain blocks? 

Any thoughts?
Cunningham can be plain because there isn't a heavy load. Vang should be plane because there will be heavy static loads. Outhaul plain for the same reason.

Running rigging is where ball bearings shine. Everywhere else they aren't needed and generally speaking simple is more rugged. I think they put them in cam cleats because a bit of play is good to have there. If they made them tight a bit of salt can make them stick open. Ball bearings can take a bit of off-axis play with out all the wear being concentrated on a single point.   

 

IStream

Super Anarchist
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Okay, I'm going to be the dissenting voice here. On my 50'er I have to be ruthless about eliminating friction in the running rigging. As part of that, I replaced all the turning blocks at the base of the mast with oversized torlon ball bearing Garhauer blocks and it was a huge help. Yes, that even includes the roller furling jib halyard, which doesn't seem to be complaining. I do have to lube them every year but that's a small price to pay (besides the big price I paid for the blocks...). 

 

El Borracho

Verified User
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Pacific Rim
Okay, I'm going to be the dissenting voice here. On my 50'er I have to be ruthless about eliminating friction in the running rigging.
Same here. Ball bearing blocks do take a level of maintenance far beyond what is usual in the sailing sport. And most failing bearings are seen on very old, sun bleached, cracking, etc. blocks and cams. Plain bearings are highly loaded as well. The pin is made as small as possible to help overcome friction. But wear and failure are hidden – apt to go unnoticed. An unmaintained plain bearing is better than a neglected ball bearing. 

 

pcoe

New member
39
1
Virginia
Sounds like plain bearing lbocks should be use at all control lines and halyard base blocks, and mainsheet will have ball bearings for ease of adjustments.

I have read a few articles on reducing friction and seems that they always promote ball or roller bearings so good to know the actual truth. 

Thanks

 

slug zitski

Super Anarchist
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worldwide
I am in the process of replacing my old blocks with new along with new lines. 

All my old blocks appear to be plain bearing type. I read that you should not change out all your blocks with ball bearings or roller bearings blocks, as they tend to potentially flatten the ball or roller under high static loads. I am not sure if this is accurate or would anyone notice over time.

But if it is, does that mean that your halyard mast base blocks would need to be plain bearing type and mainsheet and boom vang should be ball bearing blocks?

Outhaul and cunningham plain blocks? 

Any thoughts?
Not sure what you mean 

bushing ?

steel needle bearing ?

plastic bearing ?

a bushed bearing lasts a long time but has friction 

grease packed needle bearings are indestructible ,  low friction but require service

plastic  bearing , harken style are low friction but limited life span 

the lewmar range , can’t remember the name , with grease packed needle bearings are good mid price blocks 

cheap bushing blocks that are pressed together , un serviceable , should be avoided 

Pictured are grease packed bearing blocks 

8109C055-561D-471A-9368-96D2D184A4EA.jpeg

8D16CF27-F894-4855-B3A1-7CAA17AFB874.png

E1F644AB-62FA-43E9-B0EB-40F519BEA44A.png

 

Mark K

Super Anarchist
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Okay, I'm going to be the dissenting voice here. On my 50'er I have to be ruthless about eliminating friction in the running rigging. As part of that, I replaced all the turning blocks at the base of the mast with oversized torlon ball bearing Garhauer blocks and it was a huge help. Yes, that even includes the roller furling jib halyard, which doesn't seem to be complaining. I do have to lube them every year but that's a small price to pay (besides the big price I paid for the blocks...). 
 Raises an important point, that big boat loads call for roller bearings in more places than smaller boats do.  

 

P_Wop

Super Anarchist
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Bay Area, CA
FWIW, go for all roller-bearing blocks, but size them one larger than you normally would.  And wash them out and lube annually, when you do your winches.  Or wenches perhaps, as long as you entice them to help.

Exceptions are masthead sheaves, which should be plain bearing as the turn can be up to 180° and they don't move a lot.

Other exceptions are lightly loaded ones, where there will be naked Spectra rendering through them, like vang, outhaul, Cunningham and backstay cascades.  Those can all be low-friction ding-a-ling rings.

YMMV

 
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timz3818

New member
37
21
CA
If the line ever needs to move fast use roller or ball bearings (in mast sheaves exempted).  Also use them in low load parts of cascading control lines so that the cascade plays out more easily.

I'm a fan of Harken's black magic blocks for sheets and halyard turning blocks. They're not cheap, but they have very little friction and last forever. Just replace the roller assembly every decade or two.

 

Go Left

Super Anarchist
4,951
414
Seattle
Okay pretty much everywhere people are advocating plain bearing blocks you can use RopeEye type fittings. Much simpler and weight savings is immense.
The problem with the donuts in lieu of blocks is that for some lines, especially some higher-tech lines, is that the cover doesn't roll over the donut surface smoothly and steadily builds up twist on the standing part of the line.  This isn't much a problem for lines that only move a short distance, but for runners and such they can make for a kinky mess.  In my experience anyway.

We've replaced many of the Antal rings and such on my boat fairly light and powered up 50'er.  There's certainly a place for them, but not a universal fix, by any means.

 

JM1366

Member
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82
Wisconsin
What sort of boat is this? What I would choose for a 40 foot IOR boat is very different from what I'd put on a scow or J/70, for example.

For smaller, lighter boats, ball-bearing blocks are generally by far my preference. Additionally, any time you have cascaded purchase systems, the line that isn't being handled should be slick dyneema. The goal here is to cut down on friction, especially on boats that don't use winches.

You don't want adjustments to sail trim or sail controls to require any more time / crew effort than necessary, because every additional second your crew is fighting to get more vang on is an additional second that their head is in the boat rather than on the race course. If you're daysailing, presumably you're out to "have a good time", in which case cutting down on the effort needed to make sail adjustments is well worth it. 

If your boat weighs as much as a dumptruck, it might be a different story.

 

Overbored

Anarchist
711
59
So. Cal
Replaced the mast head block on the main halyard with a Harken roller bear sheave. reduced the load to raise the main by ten times. I have no use for the cheap plain bearing blocks anywhere on the boat. ball bearing ratchet blocks on the sheets also makes life easier.

 




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