I'll be making some stanchion base backing plates for my boat sometime soon,
and was wondering what size/thickness they should be. The boat is 18', GRP,
and there are no backing plates at present (3 stanchions each side). The
bolts come through into the cabin and the plates would bear against the GRP
cabin ceiling.

The plan is to use stainless steel plate, partly for corrosion resistance,
and partly because of the way the stanchion bases were aligned when they
were originally fitted - they aren't all set out such that all through-bolts
are clear of the internal cabin wall (ie, some of the nuts are very close,
such that some plates would have a slot in the outer edge, rather than three
clear holes). I feel that a softer material, such as wood or brass, might
give at the edge and not do the intended job.

What thickness of stainless should I use? 3-4mm sounds good from a
fabrication point of view, but would it be adequate?

The bases are 62mm in diameter (about 2.4") - how wide should the plates be?
I was thinking of a rectangular shape with the long side running fore/aft.
Maybe 3" wide and 6" long.

Given that the cabin ceiling isn't perfectly flat, how should I attain a
good contact over the area of the plates? Would a layer of thin (1-2mm)
rubber help? Or should any packing be solid?

What about rotating those bases that are poorly aligned, so that all three
holes are clear of the inside wall, filling the old holes and drilling new
ones?

Any other ways to approach this? Comments invited.


--
Wally
www.makearatherlonglinkthattakesyounowhere.com
Things are always clearer in the cold, post-upload light.

1/8th inch thick plates will suffice in S/S on your sized vessel. Use a
thick epoxy to "back" the plates onto a curved surface.. slightly tighten
the plate so the uncured epoxy squeezes out and trim the excess. Back-off a
bit on the nuts and allow to cure. Polishing with wax or a light coating of
oil [or some plastic wrap] on the metal will prevent the epoxy from adhering
to it.

CM

"Wally" wrote in message
...
| I'll be making some stanchion base backing plates for my boat sometime
soon,
| and was wondering what size/thickness they should be. The boat is 18',
GRP,
| and there are no backing plates at present (3 stanchions each side). The
| bolts come through into the cabin and the plates would bear against the
GRP
| cabin ceiling.
|
| The plan is to use stainless steel plate, partly for corrosion resistance,
| and partly because of the way the stanchion bases were aligned when they
| were originally fitted - they aren't all set out such that all
through-bolts
| are clear of the internal cabin wall (ie, some of the nuts are very close,
| such that some plates would have a slot in the outer edge, rather than
three
| clear holes). I feel that a softer material, such as wood or brass, might
| give at the edge and not do the intended job.
|
| What thickness of stainless should I use? 3-4mm sounds good from a
| fabrication point of view, but would it be adequate?
|
| The bases are 62mm in diameter (about 2.4") - how wide should the plates
be?
| I was thinking of a rectangular shape with the long side running fore/aft.
| Maybe 3" wide and 6" long.
|
| Given that the cabin ceiling isn't perfectly flat, how should I attain a
| good contact over the area of the plates? Would a layer of thin (1-2mm)
| rubber help? Or should any packing be solid?
|
| What about rotating those bases that are poorly aligned, so that all three
| holes are clear of the inside wall, filling the old holes and drilling new
| ones?
|
| Any other ways to approach this? Comments invited.
|
|
| --
| Wally
| www.makearatherlonglinkthattakesyounowhere.com
| Things are always clearer in the cold, post-upload light.
|
|
|

1/8th inch thick plates will suffice in S/S on your sized vessel. Use a
thick epoxy to "back" the plates onto a curved surface.. slightly tighten
the plate so the uncured epoxy

Care to actually aid the fellow and tell him what kind of epoxy?
Sheesh!

RB

CANDChelp wrote:
1/8th inch thick plates will suffice in S/S on your sized vessel. Use
a thick epoxy to "back" the plates onto a curved surface.. slightly
tighten the plate so the uncured epoxy

Care to actually aid the fellow and tell him what kind of epoxy?

Would a 'marine' epoxy be a suitable material? One with 'thick' written on
the tin? (As opposed to 'thin and runny'.) By 'thick', I take it that Mooron
means something that would be suitable as a filler, given that the idea is
to fill the gap between a flat plate and a slightly curved ceiling.

Anyway, what should I do about the paint/antifoul on the rudder? Paint
first, feather the edge and then antifoul over it, or antifoul first,
feather, and paint over the edge of the antifoul?


--
Wally
www.makearatherlonglinkthattakesyounowhere.com
Things are always clearer in the cold, post-upload light.

"Wally" wrote in message

| Anyway, what should I do about the paint/antifoul on the rudder? Paint
| first, feather the edge and then antifoul over it, or antifoul first,
| feather, and paint over the edge of the antifoul?

Since I'm not experienced with the type of paints you are using... that
would be difficult to advise on Wally. Generally I would try feather, paint
and antifoul... in that order. How thick is the paint or it's application
that would suggest the requirement for feathering? Maybe several layers of
thin, diluted applications onto a feathered surface will get the required
results.

CM

Capt. Mooron wrote:
"Wally" wrote in message

Since I'm not experienced with the type of paints you are using...
that would be difficult to advise on Wally. Generally I would try
feather, paint and antifoul... in that order. How thick is the paint
or it's application that would suggest the requirement for
feathering? Maybe several layers of thin, diluted applications onto a
feathered surface will get the required results.

It's not so much the feathering that's the question (I reckon three coats of
each), but whether I should paint to a little below the waterline first,
then antifoul on top, or antifoul a little above the waterline first, then
paint. I reckon paint first, then antifoul, but thought it would be wise to
ask.

I don't think there's a problem with the anti-foul going on top of the
paint, although I could try a little test first - I had originally just
sanded the old paint smooth to prep for priming, but, when I went to wash
the dust off by wiping down with thinners proper to the primer, I found that
the old paint was softening (so I took it back to the wood).


--
Wally
www.makearatherlonglinkthattakesyounowhere.com
Things are always clearer in the cold, post-upload light.

Old rule of painting... never apply a lacquer paint over an oil paint. The
opposite is just fine. If the thinner will thin both of the types of
paint... don't prep with thinner... use alcohol. Generally if the antifoul
is ablative it must go over the paint.

CM

"Wally" wrote in message
...
| Capt. Mooron wrote:
| "Wally" wrote in message
|
| Since I'm not experienced with the type of paints you are using...
| that would be difficult to advise on Wally. Generally I would try
| feather, paint and antifoul... in that order. How thick is the paint
| or it's application that would suggest the requirement for
| feathering? Maybe several layers of thin, diluted applications onto a
| feathered surface will get the required results.
|
| It's not so much the feathering that's the question (I reckon three coats
of
| each), but whether I should paint to a little below the waterline first,
| then antifoul on top, or antifoul a little above the waterline first, then
| paint. I reckon paint first, then antifoul, but thought it would be wise
to
| ask.
|
| I don't think there's a problem with the anti-foul going on top of the
| paint, although I could try a little test first - I had originally just
| sanded the old paint smooth to prep for priming, but, when I went to wash
| the dust off by wiping down with thinners proper to the primer, I found
that
| the old paint was softening (so I took it back to the wood).
|
|
| --
| Wally
| www.makearatherlonglinkthattakesyounowhere.com
| Things are always clearer in the cold, post-upload light.
|
|
|

Would a 'marine' epoxy be a suitable material? One with 'thick' written on
the tin? (As opposed to 'thin and runny'.)

Good god.

RB

Use West System epoxy, they sell it in two parts, an epoxy and the hardener.
They sell different types of epoxy for different applications, don't know
offhand which epoxy you need. They also sell thickener, you can make the
epoxy whatever consistency you like, from runny to thicker than peanut
butter. Don't be put off by the cost, the stuff has a fairly long shelf
life, you've indicated that you have at least one other use for it on this
particular project, filling the holes. Don't buy the kits in the small
pouches buy the small cans.
http://www.westsystem.com/

John Cairns

"Wally" wrote in message
...
Would a 'marine' epoxy be a suitable material? One with 'thick' written
on
the tin? (As opposed to 'thin and runny'.) By 'thick', I take it that
Mooron
means something that would be suitable as a filler, given that the idea is
to fill the gap between a flat plate and a slightly curved ceiling.
--
Wally
www.makearatherlonglinkthattakesyounowhere.com
Things are always clearer in the cold, post-upload light.

CANDChelp wrote:
Would a 'marine' epoxy be a suitable material? One with 'thick'
written on the tin? (As opposed to 'thin and runny'.)

Good god.

Oh, should I get one with an irony constitution?


--
Wally
www.makearatherlonglinkthattakesyounowhere.com
Things are always clearer in the cold, post-upload light.