Interesting. Do you remember where it was published?

/Martin

The online copy was published by madforsailing.com. I lost the link when they went from free to subscription.

The surprise in the British study was that plain bearing blocks had lower initial friction than ball bearing blocks The theory was the plastic balls formed a temporary flat spot under static loads and required extra force until the ball bearings assmed a more rounded shape.

I am a madforsailing.com subscriber and I have searched their web with little luck. I find an old (late 2001) debate on this and some of it may be interpreted as referring to a published test, a test I simply can't find. I will write them and ask.

/Martin

well done Martin

your study post of the week in sailing anarchy

http://www.sailinganarchy.com/index_page1.php

think you won a t-shirt

I don't know about you, but I have ball bearing blocks for two reasons :

-1- the run smoother when very little load is placed on them, at least that is what I think; this is attractive for the light wind days.

-2- They don't jam up as easily with sand and salt. I have a few slide bearing blocks on my boat (no ball bearing) and indeed they do easily jam up with dirt and salt and are harder to get unstuck.

Wouter

Oops

/Martin

-1- is my experience too, even when in my 'lab' but the recorded numbers tell me a somewhat different story.

-2- Salt and sand are non-issues where I live and sail these days. When still in my native Gothenburg, salt was a problem and it really payed off to rinse (all types of) blocks and lines.

/Martin