Best Bedding for Fixed Port Light Rebuild

On Oct 2, 6:16 pm, Marc Auslander <marcsli... DeleteThis @optonline.NOSPAM.net>
wrote:
> I'm rebuilding the Port Light on a Tartan 30. It consists of two
> aluminium bezels and a plexiglass "window". The two bezels are held
> together by barrel nuts and bolts, and overlap the coach sides and the
> plexiglass.
>
> I believe I need to seal the outer bezel to both the plexiglass and
> the outside of the cabin top with some sealant. It looks like the job
> was done with silicone by the factory, 30 years ago.
>
> I've seen some claims that there are good and bad forms of silicone
> for this. Other claims that something like Boatlife is a better
> choice.
>
> Obviously, I want to use something that can be undone if it leaks
> again - no 5200!
>
> Suggestions?
> --

Dow 795.
 >> Stay informed about: Best Bedding for Fixed Port Light Rebuild 

Oh No!
Never Silicone. Silicone is terrible.
SikaFlex 295UV is the right stuff. My Opinion.

> Dow 795.
>
 >> Stay informed about: Best Bedding for Fixed Port Light Rebuild 

"Dan" wrote:
..
> Oh No!
> Never Silicone. Silicone is terrible
..
>> SikaFlex 295UV is the right stuff. My Opinion.
>
> > Dow 795.

What does SikaFlex295 have to do with silicone?

Lew
 >> Stay informed about: Best Bedding for Fixed Port Light Rebuild 

On Oct 9, 1:21 pm, Dan <"dhapp-at-gotsky,com"> wrote:
> Oh No!
> Never Silicone. Silicone is terrible.
> SikaFlex 295UV is the right stuff. My Opinion.


Hey there......

Dow COrning 795 aint your grandpa's silicone seal........... think
"structural" silicone. Really heavy duty industrial hold twin tower
windows in w/o fastners really thick kinda silicone.

get their spec sheet and check the lap strength for diffrent materials
and strech numbers. I used it when I fabricated my 7"x15"x 3/8"
polycarb dead lights. Min DC 795 thickness :1/8". Of course fastned
with ten 316L 1/4"x20 PH MS.



Bob
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Nothing Lew, that;s why it's good. Silicone bad. I hate silicone and
won't use it on a boat. Period!

>What does SikaFlex295 have to do with silicone?
>
>Lew
>
>
 >> Stay informed about: Best Bedding for Fixed Port Light Rebuild 

"Bob" <freya2go.RemoveThis@yahoo.com> wrote in message
news:1192004492.548042.23000@50g2000hsm.googlegroups.com...

> Dow COrning 795 aint your grandpa's silicone seal........... think
> "structural" silicone. Really heavy duty industrial hold twin tower
> windows in w/o fastners really thick kinda silicone.
>
> get their spec sheet and check the lap strength for diffrent materials
> and strech numbers. I used it when I fabricated my 7"x15"x 3/8"
> polycarb dead lights. Min DC 795 thickness :1/8". Of course fastned
> with ten 316L 1/4"x20 PH MS.
>
At the risk of (1) being exposed as a boatbuilding dunce or (2) even worse,
starting a thread as hotly contested as the hypotheteical 40' vertical
saltwater still, the comment about Dow Corning 795 leads me to ask a (naive)
question.

Could this high-strength, high-grab, somewhat flexible adhesive, or one
somewhat similar, be used to build a boat from aluminum panels, somewhat the
way epoxy is used for stitch-and-glue with plywood?

I realize there would have to be a lot of modifications to the construction
process. But is the concept reasonable with today's adhesives? Certainly DC
795 seems to have no trouble bonding to aluminum.

(Dow says 795 is not for use on surfaces continuously under water, so that
would be a problem for anything except trailered boats or dinghy-type uses.
But again, I'm just raising the question, not proposing it as a real option.
And there may be other adhesives that would be OK for underwater
applications.)

Alex
 >> Stay informed about: Best Bedding for Fixed Port Light Rebuild 

"Alex" wrote:

> At the risk of (1) being exposed as a boatbuilding dunce or (2) even
> worse, starting a thread as hotly contested as the hypotheteical 40'
> vertical saltwater still, the comment about Dow Corning 795 leads me to
> ask a (naive) question.
>
> Could this high-strength, high-grab, somewhat flexible adhesive, or one
> somewhat similar, be used to build a boat from aluminum panels, somewhat
> the way epoxy is used for stitch-and-glue with plywood?
>
> I realize there would have to be a lot of modifications to the
> construction process. But is the concept reasonable with today's
> adhesives? Certainly DC 795 seems to have no trouble bonding to aluminum.
>
> (Dow says 795 is not for use on surfaces continuously under water, so that
> would be a problem for anything except trailered boats or dinghy-type
> uses. But again, I'm just raising the question, not proposing it as a real
> option. And there may be other adhesives that would be OK for underwater
> applications.)


You might want to contact SikaFlex tech service (Metro Detroit) and ask some
of these questions.

Lew
 >> Stay informed about: Best Bedding for Fixed Port Light Rebuild 

On Fri, 12 Oct 2007 20:39:24 -0700, "Lew Hodgett"
<lewhodgett.RemoveThis@earthlink.net> wrote:

>
>"Alex" wrote:
>
>> At the risk of (1) being exposed as a boatbuilding dunce or (2) even
>> worse, starting a thread as hotly contested as the hypotheteical 40'
>> vertical saltwater still, the comment about Dow Corning 795 leads me to
>> ask a (naive) question.
>>
>> Could this high-strength, high-grab, somewhat flexible adhesive, or one
>> somewhat similar, be used to build a boat from aluminum panels, somewhat
>> the way epoxy is used for stitch-and-glue with plywood?
>>
>> I realize there would have to be a lot of modifications to the
>> construction process. But is the concept reasonable with today's
>> adhesives? Certainly DC 795 seems to have no trouble bonding to aluminum.
>>
>> (Dow says 795 is not for use on surfaces continuously under water, so that
>> would be a problem for anything except trailered boats or dinghy-type
>> uses. But again, I'm just raising the question, not proposing it as a real
>> option. And there may be other adhesives that would be OK for underwater
>> applications.)
>
>
>You might want to contact SikaFlex tech service (Metro Detroit) and ask some
>of these questions.
>
>Lew


Years ago I read an article about a British engineering student who
built a race car as his "Theses". He wanted the body to fail
progressively and ended up gluing the aluminum body panels together
using an adhesive made by locktite. You might have a look at their
literature.


Bruce in Bangkok
(brucepaigeATgmailDOTcom)
 >> Stay informed about: Best Bedding for Fixed Port Light Rebuild 

brucedpaige.RemoveThis@gmail.com wrote:

> On Fri, 12 Oct 2007 20:39:24 -0700, "Lew Hodgett"
> <lewhodgett.RemoveThis@earthlink.net> wrote:
>
>
>>"Alex" wrote:
>>
>>
>>>At the risk of (1) being exposed as a boatbuilding dunce or (2) even
>>>worse, starting a thread as hotly contested as the hypotheteical 40'
>>>vertical saltwater still, the comment about Dow Corning 795 leads me to
>>>ask a (naive) question.
>>>
>>>Could this high-strength, high-grab, somewhat flexible adhesive, or one
>>>somewhat similar, be used to build a boat from aluminum panels, somewhat
>>>the way epoxy is used for stitch-and-glue with plywood?
>>>
>>>I realize there would have to be a lot of modifications to the
>>>construction process. But is the concept reasonable with today's
>>>adhesives? Certainly DC 795 seems to have no trouble bonding to aluminum.
>>>
>>>(Dow says 795 is not for use on surfaces continuously under water, so that
>>>would be a problem for anything except trailered boats or dinghy-type
>>>uses. But again, I'm just raising the question, not proposing it as a real
>>>option. And there may be other adhesives that would be OK for underwater
>>>applications.)
>>
>>
>>You might want to contact SikaFlex tech service (Metro Detroit) and ask some
>>of these questions.
>>
>>Lew
>
>
>
> Years ago I read an article about a British engineering student who
> built a race car as his "Theses". He wanted the body to fail
> progressively and ended up gluing the aluminum body panels together
> using an adhesive made by locktite. You might have a look at their
> literature.
>
>
> Bruce in Bangkok
> (brucepaigeATgmailDOTcom)


Loctite (now owned by another company)U-05FL 2 part urethane.. Great
bond to aluminum (with proper prep).

There is another guy I know of using methacrylate for the same concept.

You have to use rivets to hold the large panels in place until it cures
and to provide shear strength.

At the rate I am building mine, I'll be done in another year or so and
let you know how it works then. So far, it works well. The only issue is
the pot time, but that can be overcome with a bit of planning and some
help from friends.



--
“TANSTAAFL”

____________________________________________________________________________

But - there is a point where criticism, even offered in the guise of
love, moves past the point of correction and to the point of
destruction. It's a subtle line, but it exists.
 >> Stay informed about: Best Bedding for Fixed Port Light Rebuild 

On Sat, 13 Oct 2007 01:03:29 GMT, "Alex"
<tuchasoffentisch.TakeThisOut@_NO_SPAM_gmail.com> wrote:


>Could this high-strength, high-grab, somewhat flexible adhesive, or one
>somewhat similar, be used to build a boat from aluminum panels, somewhat the
>way epoxy is used for stitch-and-glue with plywood?

>Alex
>


There was a light airplane built with glued wing panels - they were
aluminum as I recall which is still flying in some numbers.
So it can be done

Brian W
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On Sat, 13 Oct 2007 01:03:29 GMT, "Alex"
<tuchasoffentisch.RemoveThis@_NO_SPAM_gmail.com> wrote:

>
>"Bob" <freya2go.RemoveThis@yahoo.com> wrote in message
>news:1192004492.548042.23000@50g2000hsm.googlegroups.com...
>
>> Dow COrning 795 aint your grandpa's silicone seal........... think
>> "structural" silicone. Really heavy duty industrial hold twin tower
>> windows in w/o fastners really thick kinda silicone.
>>
>> get their spec sheet and check the lap strength for diffrent materials
>> and strech numbers. I used it when I fabricated my 7"x15"x 3/8"
>> polycarb dead lights. Min DC 795 thickness :1/8". Of course fastned
>> with ten 316L 1/4"x20 PH MS.
>>
>At the risk of (1) being exposed as a boatbuilding dunce or (2) even worse,
>starting a thread as hotly contested as the hypotheteical 40' vertical
>saltwater still, the comment about Dow Corning 795 leads me to ask a (naive)
>question.
>
>Could this high-strength, high-grab, somewhat flexible adhesive, or one
>somewhat similar, be used to build a boat from aluminum panels, somewhat the
>way epoxy is used for stitch-and-glue with plywood?
>
>I realize there would have to be a lot of modifications to the construction
>process. But is the concept reasonable with today's adhesives? Certainly DC
>795 seems to have no trouble bonding to aluminum.
>
>(Dow says 795 is not for use on surfaces continuously under water, so that
>would be a problem for anything except trailered boats or dinghy-type uses.
>But again, I'm just raising the question, not proposing it as a real option.
>And there may be other adhesives that would be OK for underwater
>applications.)
>
>Alex
>
>
That is how I built my airplane floats. Stiched together with blind
rivets and seams sealed with sikaflex 1A construction adhesive.
 >> Stay informed about: Best Bedding for Fixed Port Light Rebuild 

On Oct 12, 6:03 pm, "Alex" <tuchasoffentisch DeleteThis @_NO_SPAM_gmail.com>
wrote:
> "Bob" <freya... DeleteThis @yahoo.com> wrote in message
>

> At the risk of (1) being exposed as a boatbuilding dunce or (2) even worse,
> starting a thread as hotly contested as the hypotheteical 40' vertical
> saltwater still, the comment about Dow Corning 795 leads me to ask a (naive)
> question.
>
> Could this high-strength, high-grab, somewhat flexible adhesive, or one
> somewhat similar, be used to build a boat from aluminum panels, somewhat the
> way epoxy is used for stitch-and-glue with plywood?
> Alex


Good idea..... Years ago I worked at a research oyster hatchery. They
used silicone seal to bond 200 gallon glass tanks. The tanks were set
into a 2"x4" wood frame. But the glass panes were all bonded with
clear silicone seal...... never a failure

I would think 5200 might work for a quick boat. I used it to patch all
the lose rivits and holes in an 18' Grumman canoe that a bunch of
drunk cowboys abused for 10 years.

Bob
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