I just took out a leaking Signet Knotlog through hull and need to put
a new one in the hole with proper bedding. For some reason, the new
fitting has a slightly thinner flange. The original hole was also not
to the tolerances I would have liked to have found. The means that
there will be quite a bit of bedding compound behind the flange.

My plan is to put the fitting in the hole flush with the hole and let
the compound set up before taking up on the nut inside. I could also
put some wax on the fitting, set it in epoxy paste, remove and clean
it, and then do final installation to achieve a thinner gasket of
bedding compound.

Any recommendations on which goop to used if I go the first route and
want something that will take the compression of the nut and hold
together?

Any strong feelings that I should do it in two steps to try and get
the tapered flange hole to tighter tolerances? If this was a piping
through hull where there could be stress on the fitting from the
inside, I would definitely rework the hole but the wire for the speed
sensor isn’t going to put any strain on it.

--

Roger Long

On Sun, 05 Mar 2006 12:09:24 GMT, "Roger Long"
wrote:

I could also
put some wax on the fitting, set it in epoxy paste, remove and clean
it, and then do final installation to achieve a thinner gasket of
bedding compound.

That's the approach I'd be inclined to take but there are some
caveats. It is important not to get epoxy on the threads of the
transducer because that will be difficult to remove, even with wax or
mold release. A layer of masking tape over the threads might do the
trick.

The second issue that I see is picking the right time to remove the
transducer before the epoxy is totally cured. Too soon and the epoxy
will sag, too late and you might not be able to remove the transducer.

What about that epoxy putty that comes in a bar that you kneed
together? They call is swimming pool patch sometimes. I've used it
other places and it seems to cure quite hard as well as not sticking
or sagging.

--

Roger Long



"Wayne.B" wrote in message
...
On Sun, 05 Mar 2006 12:09:24 GMT, "Roger Long"
wrote:

I could also
put some wax on the fitting, set it in epoxy paste, remove and clean
it, and then do final installation to achieve a thinner gasket of
bedding compound.

That's the approach I'd be inclined to take but there are some
caveats. It is important not to get epoxy on the threads of the
transducer because that will be difficult to remove, even with wax
or
mold release. A layer of masking tape over the threads might do the
trick.

The second issue that I see is picking the right time to remove the
transducer before the epoxy is totally cured. Too soon and the
epoxy
will sag, too late and you might not be able to remove the
transducer.

On Sun, 05 Mar 2006 14:48:33 GMT, "Roger Long"
wrote:

What about that epoxy putty that comes in a bar that you kneed
together? They call is swimming pool patch sometimes. I've used it
other places and it seems to cure quite hard as well as not sticking
or sagging.

Good thought, hadn't considered it. Adhesion is probably not as good
as wet resin but it doesn't really need to be in this application.

I'd still protect the threads however.

In article ,
"Roger Long" wrote:

I just took out a leaking Signet Knotlog through hull and need to put
a new one in the hole with proper bedding. For some reason, the new
fitting has a slightly thinner flange. The original hole was also not
to the tolerances I would have liked to have found. The means that
there will be quite a bit of bedding compound behind the flange.

Having "unbedded" a few through hulls on Xan, I would WELCOME the "lack
of tolerance" in the hole. Where there was a thick layer of caulk, the
through-hull had to be cut out. When it was thin, the assembly spun
before I could even get the gate valve off. (They must have used 5200 or
similar.)

I don't recommend using anything "hard" like epoxy, as the hull expands
and contracts slightly over the year due to temperature and moisture
level. Put a plywood backing plate between the nut and hull, and let
some caulk get in there, but don't caulk the nut on.


--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
Xan's Pages: http://members.dca.net/jerelull/X-Main.html
Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/