On Tue, 12 Apr 2005 17:30:08 GMT, engsol
wrote:

On Tue, 12 Apr 2005 14:23:48 GMT, Don W wrote:

Jim Richardson wrote:

What about just using orings? should be easy enough to size, and placing
them on the bolts, before laying the track down (the second time, doing
the drilling one at a time sounds like a good idea to me) Neoprene
orings should survive well, but maybe I am missing something?

I've thought about that as well. It seems to me that using caulk to try to seal
something that moves around even a little bit is a temporary solution at best.
I've now got numerous small leaks in the deck of my boat which showed up only 2-3
years after being re-bedded by the PO. It would be nice to fix these in a way
that didn't need to be redone every few years.

I don't have a solution right now, other than to point to the sealer washers around
the screws on my metal roof. A roof is exposed to terrific heat during the summer and
it gets flexed slightly by the wind, and even hail yet maintains a watertight seal for
decades.

And Wayne: The fact that boats are usually not done that way _can_ be an indication that it
isn't a good idea, but...

Anyone have experience with using a sealer washer to seal around the bolts and screws that
pierce the deck on their boat?

Don W.

Thought provoking topic.
The idea of using O rings may be a good one. I think the key would be the
installation. Just sqeezing the O ring betwen track and deck doesn't (to me)
seem quite the right method, but I can't explain why.

Would counter-boring the hole to a depth of 1/2 the diameter of the O ring to
provide a "seat" for the ring work? If all the componets were sized properly,
I can see the O ring creating pressure on the track, the sides of the hole, and
the bolt, with the deck carrying the load of the track.

Would coating the O ring with a bit of waterproof grease before installation help?

One problem I see with my suggestion....counter-boring the O ring recess
straight....but then, I wonder if a bit of "tilt" would really matter?

I may divide the track in thirds, and test a few things. It's only water grin
Norm B

In engineering usage, the rule of thumb for an o-ring fit with no
slip/rotation required is to machine the sidewalls of the groove to
nominal o-ring thickness, and to machine the depth of the groove to
90% of the o-ring's thickness. This will expand the o-ring material to
occupy half the airspace inside the groove when it is fully compressed

Brian Whatcott Altus, OK