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sel1 December 11th 04 11:55 PM

backing plates
 
Hi all,

I want to put on backing plates for all the stuff attached to the transom
(exhaust ports, swim platform, steering arms etc). Through continually
snugging them, the previous owner has burried a couple of nuts through the
glass! I am really new to all this but the first thing that comes to mind is
reaction between two metals. If I use stainless bolts, could I use aluminum
for backing plates or maybe I should use something else, or maybe I
shouldn't do this at all?

Still asking and not able to answer much yet.

Thanks, Steve




Calif Bill December 12th 04 12:22 AM

Use some stainless backing plates and Nyloc nuts.

"sel1" wrote in message
...
Hi all,

I want to put on backing plates for all the stuff attached to the transom
(exhaust ports, swim platform, steering arms etc). Through continually
snugging them, the previous owner has burried a couple of nuts through the
glass! I am really new to all this but the first thing that comes to mind

is
reaction between two metals. If I use stainless bolts, could I use

aluminum
for backing plates or maybe I should use something else, or maybe I
shouldn't do this at all?

Still asking and not able to answer much yet.

Thanks, Steve






K. Smith December 12th 04 01:00 AM

sel1 wrote:
Hi all,

I want to put on backing plates for all the stuff attached to the transom
(exhaust ports, swim platform, steering arms etc). Through continually
snugging them, the previous owner has burried a couple of nuts through the
glass! I am really new to all this but the first thing that comes to mind is
reaction between two metals. If I use stainless bolts, could I use aluminum
for backing plates or maybe I should use something else, or maybe I
shouldn't do this at all?

Still asking and not able to answer much yet.

Thanks, Steve




To do it properly takes a little time but doesn't cost a single cent
more as in;

(i) Aluminium is OK say;
(a) 1/4"
(b) Size/shape of the backing is up to you, usually the available space
will dictate the shape size etc, the rule is; if it looks right it
probably is:-)
(b) it's not under water as such so dissimilar metals shouldn't be an
issue (even with stainless you'd still need to ensure the same stainless
as the bolts say 316 vs 3xx or it corrodes anyway:-)
(c) aluminium is much easier to work & you can even drill it in situ
from the outside if you have a tricky nook or cranny.

(ii) Chamfer just the outer perimeter of the plates away from where
they'll pull against the hull, if you leave a sharp edge it can cut into
the outer glass under load & leave a crack in the flow or gelcoat for
water to get in.

(iii) You should try to seal inside all the through hull holes:
(a) particularly if it's the cored transom
(b) Coat the holes right through with any of the good epoxy fillers, then
(c) push the bolts back in while it's wet, having given the bolt a good
coat of grease first (dipped in candle wax works too).
(d) Once epoxy has gelled you should be able to get your bolts back out
with a spanner, leaving a good protection for the transom core (usually
plywood) & a good fit for the bolt.

(iv) When ready to put it all together again;
(a) use plenty of any of the good sealants, sadly price is a good
indicator so any marine recommended 3M or marine sikaflex (German?? not
sure) is OK.
(b) Clean the hull, parts, holes, bolts etc with solvent so the sealant
can adhere.
(c) Put all the bolts in & tighten the nuts (don't turn the bolts if
you can avoid it, it messes up the sealant) just tight enough to get all
the parts mated & snug, don't over tighten at this stage,
(d) get rid of excess squeezed out sealant with whatever solvent.
(e) Let the whole thing set for a while at least a day but longer is
OK, so the sealant can fully cure.
(f) Now you can tighten it all up, but again make sure someone holds
the bolts so they can't turn & you just tighten the nuts.

It'll be ticketyboo:-)


K

Snafu December 12th 04 05:23 AM

I just saw a nice chart of similar and dissimilar metals last week on the
Jamestown Distributors web site. It's he
http://www.jamestowndistributors.com...compmetals.asp

JD has a lot of hardware and information for boatbuilders and
do-it-yourselfers.

"sel1" wrote in message
...
Hi all,

I want to put on backing plates for all the stuff attached to the transom
(exhaust ports, swim platform, steering arms etc). Through continually
snugging them, the previous owner has burried a couple of nuts through the
glass! I am really new to all this but the first thing that comes to mind

is
reaction between two metals. If I use stainless bolts, could I use

aluminum
for backing plates or maybe I should use something else, or maybe I
shouldn't do this at all?

Still asking and not able to answer much yet.

Thanks, Steve






sel1 December 12th 04 04:03 PM

Thanks so much for the detail K, pretty straight forward. You say aluminum
is OK. As in not the best material?

Most of the work will be above the water line but my swim platform brackets
go below the water line and they are steel angle iron (probably home made).
Any ideas on what kind of support system I could use so that the it doesn't
have to go below water line? Either that or I switch to aluminum angle
pieces and stainless bolts. Aluminum should be OK below water line? Previous
owner didn't even use stainless bolts so they were really tough to get off.

To do it properly takes a little time but doesn't cost a single cent
more as in;

(i) Aluminium is OK say;
(a) 1/4"
(b) Size/shape of the backing is up to you, usually the available space
will dictate the shape size etc, the rule is; if it looks right it
probably is:-)
(b) it's not under water as such so dissimilar metals shouldn't be an
issue (even with stainless you'd still need to ensure the same stainless
as the bolts say 316 vs 3xx or it corrodes anyway:-)
(c) aluminium is much easier to work & you can even drill it in situ
from the outside if you have a tricky nook or cranny.

(ii) Chamfer just the outer perimeter of the plates away from where
they'll pull against the hull, if you leave a sharp edge it can cut into
the outer glass under load & leave a crack in the flow or gelcoat for
water to get in.

(iii) You should try to seal inside all the through hull holes:
(a) particularly if it's the cored transom
(b) Coat the holes right through with any of the good epoxy fillers, then
(c) push the bolts back in while it's wet, having given the bolt a good
coat of grease first (dipped in candle wax works too).
(d) Once epoxy has gelled you should be able to get your bolts back out
with a spanner, leaving a good protection for the transom core (usually
plywood) & a good fit for the bolt.

(iv) When ready to put it all together again;
(a) use plenty of any of the good sealants, sadly price is a good
indicator so any marine recommended 3M or marine sikaflex (German?? not
sure) is OK.
(b) Clean the hull, parts, holes, bolts etc with solvent so the sealant
can adhere.
(c) Put all the bolts in & tighten the nuts (don't turn the bolts if
you can avoid it, it messes up the sealant) just tight enough to get all
the parts mated & snug, don't over tighten at this stage,
(d) get rid of excess squeezed out sealant with whatever solvent.
(e) Let the whole thing set for a while at least a day but longer is
OK, so the sealant can fully cure.
(f) Now you can tighten it all up, but again make sure someone holds
the bolts so they can't turn & you just tighten the nuts.

It'll be ticketyboo:-)

K




Don White December 12th 04 04:29 PM


"sel1" wrote in message
...
Thanks so much for the detail K, pretty straight forward. You say aluminum
is OK. As in not the best material?

I tried both 1/8" ss plate and 1/4" aluminum plate this summer. Unless you
have a drill press forget the ss. damn hard to cut or drill. On sume of
the aluminum backing plates, wehere the ss bolts and washes came in touch, I
used cutout plastic washers made of ice cream containers and liquid
electrical tape.



JamesgangNC December 12th 04 06:01 PM

I use those hard 1/2" thick cutting boards with ss fender washers and nylock
nuts. Also I put epoxy between the backing plate and fiberglass. The
cutting board material cuts and drills like wood. Obviously it will never
rot and will not react with the bolts. I put my wake tower on 4 years ago
using them and I sometimes pull 6 people on 2 super screamer tubes from the
tower with no problems.

"sel1" wrote in message
...
Hi all,

I want to put on backing plates for all the stuff attached to the transom
(exhaust ports, swim platform, steering arms etc). Through continually
snugging them, the previous owner has burried a couple of nuts through the
glass! I am really new to all this but the first thing that comes to mind
is
reaction between two metals. If I use stainless bolts, could I use
aluminum
for backing plates or maybe I should use something else, or maybe I
shouldn't do this at all?

Still asking and not able to answer much yet.

Thanks, Steve






Jim December 12th 04 06:25 PM

I'm waiting to see if anyone suggests to look for the reason for the
loose bolts, like rotten plywood core. So far there is a lot of good
info on backing plates.

Out drive boats are usually built with a plywood core in the transom,
because of the loads the transom takes. I doubt you'll find foam.

If you have some rot, there's no choice on the fix. Backing plates
isn't it.
Jim



Snafu December 12th 04 06:30 PM

I like this idea of using a white plastic cutting board for a backing plate.
I'm going to file that one away for myself.

Thanks

"JamesgangNC" wrote in message
nk.net...
I use those hard 1/2" thick cutting boards with ss fender washers and

nylock
nuts. Also I put epoxy between the backing plate and fiberglass. The
cutting board material cuts and drills like wood. Obviously it will never
rot and will not react with the bolts. I put my wake tower on 4 years ago
using them and I sometimes pull 6 people on 2 super screamer tubes from

the
tower with no problems.




Calif Bill December 12th 04 06:38 PM

Use a cutting oil when drilling the SS.

"Don White" wrote in message
...

"sel1" wrote in message
...
Thanks so much for the detail K, pretty straight forward. You say

aluminum
is OK. As in not the best material?

I tried both 1/8" ss plate and 1/4" aluminum plate this summer. Unless

you
have a drill press forget the ss. damn hard to cut or drill. On sume

of
the aluminum backing plates, wehere the ss bolts and washes came in touch,

I
used cutout plastic washers made of ice cream containers and liquid
electrical tape.





sel1 December 12th 04 06:46 PM

One would suspect rot, but I just had the boat surveyed and the only spot in
question was where the steering arms came through the transom - some
delamination. Once I took out the steering arms, sure enough the wood is a
bit pulpy. Previous owner left pratically desintegrated boots as they were,
for obviously a very long time. Albeit above the water line, it was pretty
wet in there. Might have to replace wood in that area. In the spot where the
bolts appeared to be sunk in was around the exhaust ports, which I have
removed and the wood looks pretty good actually, but I'm just a beginner
:o).

I guess I'll have the other areas checked out again in the spring.


"Jim" wrote in message
ink.net...
I'm waiting to see if anyone suggests to look for the reason for the
loose bolts, like rotten plywood core. So far there is a lot of good
info on backing plates.

Out drive boats are usually built with a plywood core in the transom,
because of the loads the transom takes. I doubt you'll find foam.

If you have some rot, there's no choice on the fix. Backing plates
isn't it.
Jim





Short Wave Sportfishing December 12th 04 06:47 PM

On Sun, 12 Dec 2004 18:01:09 GMT, "JamesgangNC"
wrote:

I use those hard 1/2" thick cutting boards with ss fender washers and nylock
nuts. Also I put epoxy between the backing plate and fiberglass. The
cutting board material cuts and drills like wood.


It's called Starboard. There is also a variant out there, but I can't
remember the name.

Obviously it will never
rot and will not react with the bolts. I put my wake tower on 4 years ago
using them and I sometimes pull 6 people on 2 super screamer tubes from the
tower with no problems.


Pardon my ignorance, but what is a wake board?

Later,

Tom

Short Wave Sportfishing December 12th 04 08:11 PM

On Sun, 12 Dec 2004 13:46:12 -0500, "sel1"
wrote:

One would suspect rot, but I just had the boat surveyed and the only spot in
question was where the steering arms came through the transom - some
delamination. Once I took out the steering arms, sure enough the wood is a
bit pulpy. Previous owner left pratically desintegrated boots as they were,
for obviously a very long time. Albeit above the water line, it was pretty
wet in there. Might have to replace wood in that area. In the spot where the
bolts appeared to be sunk in was around the exhaust ports, which I have
removed and the wood looks pretty good actually, but I'm just a beginner
:o).

I guess I'll have the other areas checked out again in the spring.


What sometimes happens is that the bolts get over torqued compressing
the wood and, essentially, destroying any adhesive properties of the
glue used on the veneer layers of the plywood. Once the glue bond is
broken and the wood cells compressed (destroying them), the whole
thing becomes suspect.

You can sometimes salvage the wood with epoxy, but that's not common
in large scale dry or wet rot. You can guarantee that if the holes
are a "little" pulpy, the whole thing is compromised. Repairs can be
made by cutting out the rot and replacing with a epoxy, a plug and
fiberglass if the area isn't too large. If the rot is extensive, then
it's time to replace it all.

Go to a local dollar store and buy a small rubber hammer for a buck
and thump the entire transom. Any "dead' sounding thumps (and you
will know the difference once you do it) is where the wood is shot.

On my Ranger, as well as the Contender, I use Starboard if I'm
installing something that requires a backing plate. With a little
patience, you can make Starboard do just about what you want to do
and if you have any engineering experience, it's perfect for
customizing.

Good luck.

Later,

Tom

Snafu December 12th 04 10:24 PM

"Short Wave Sportfishing" wrote in message
...
On Sun, 12 Dec 2004 18:01:09 GMT, "JamesgangNC"
wrote:

I use those hard 1/2" thick cutting boards with ss fender washers and

nylock
nuts. Also I put epoxy between the backing plate and fiberglass. The
cutting board material cuts and drills like wood.


It's called Starboard. There is also a variant out there, but I can't
remember the name.

Obviously it will never
rot and will not react with the bolts. I put my wake tower on 4 years

ago
using them and I sometimes pull 6 people on 2 super screamer tubes from

the
tower with no problems.


Pardon my ignorance, but what is a wake board?

Later,

Tom


As a snowboard is to snow skis, a wakeboard is to water skis.

http://www.sunrizedigitalmedia.com/B...2%29%20076.htm

:^)



Snafu December 12th 04 10:26 PM


"Harry Krause" wrote in message
...
Snafu wrote:
I like this idea of using a white plastic cutting board for a backing

plate.
I'm going to file that one away for myself.

Thanks



Boston Whaler used (and may still use) plastic backing plates for
hardware on its older Montauk series. If you go with the cutting board
approach, make sure you use BIG round flat washers to spread out the load.


Yup, I would definitely used stainless fender washers and stainless nylock
nuts as JamesGang suggested.



RichG December 12th 04 11:41 PM

Assuming "Starboard" is similar in strength to Corion, or its many
copy-cats.......You may be able pickup free sink cut-outs from a local
kitchen cabinet dealer. A lot of Corion style sinks are molded-in these
days, but some people still prefer the drop-in sink...leaving a Corion
cut-out to be thrown away. RichG TX

--
RichG manager, Carolina Skiff Owners Group on MSN
http://groups.msn.com/CarolinaSkiffOwners
..



Short Wave Sportfishing December 12th 04 11:58 PM

On Sun, 12 Dec 2004 23:41:28 GMT, "RichG"
wrote:

Assuming "Starboard" is similar in strength to Corion, or its many
copy-cats.......You may be able pickup free sink cut-outs from a local
kitchen cabinet dealer. A lot of Corion style sinks are molded-in these
days, but some people still prefer the drop-in sink...leaving a Corion
cut-out to be thrown away. RichG TX


I'm surprised you've never heard of it - it's used on fiberglass boats
for cabinet/storage/baitwell covers/doors and is the stuff used in
electronic boxes.

http://www.kingplastic.com/Products/...ardFamily.aspx

Later,

Tom

sel1 December 13th 04 12:29 AM

Tom,

re your comment on over torquing, the nuts are pretty small (3/8) and I
could easily see that happening but Jim has me thinking more of rot (wet or
dry) than I care to now. The transom is about 12' X 3.5' and the plywood
core is at least 2" thick. Yikes! $$$$


"Short Wave Sportfishing" wrote in message
...
On Sun, 12 Dec 2004 13:46:12 -0500, "sel1"
wrote:

One would suspect rot, but I just had the boat surveyed and the only spot

in
question was where the steering arms came through the transom - some
delamination. Once I took out the steering arms, sure enough the wood is

a
bit pulpy. Previous owner left pratically desintegrated boots as they

were,
for obviously a very long time. Albeit above the water line, it was

pretty
wet in there. Might have to replace wood in that area. In the spot where

the
bolts appeared to be sunk in was around the exhaust ports, which I have
removed and the wood looks pretty good actually, but I'm just a beginner
:o).

I guess I'll have the other areas checked out again in the spring.


What sometimes happens is that the bolts get over torqued compressing
the wood and, essentially, destroying any adhesive properties of the
glue used on the veneer layers of the plywood. Once the glue bond is
broken and the wood cells compressed (destroying them), the whole
thing becomes suspect.

You can sometimes salvage the wood with epoxy, but that's not common
in large scale dry or wet rot. You can guarantee that if the holes
are a "little" pulpy, the whole thing is compromised. Repairs can be
made by cutting out the rot and replacing with a epoxy, a plug and
fiberglass if the area isn't too large. If the rot is extensive, then
it's time to replace it all.

Go to a local dollar store and buy a small rubber hammer for a buck
and thump the entire transom. Any "dead' sounding thumps (and you
will know the difference once you do it) is where the wood is shot.

On my Ranger, as well as the Contender, I use Starboard if I'm
installing something that requires a backing plate. With a little
patience, you can make Starboard do just about what you want to do
and if you have any engineering experience, it's perfect for
customizing.

Good luck.

Later,

Tom




Short Wave Sportfishing December 13th 04 01:01 AM

On Sun, 12 Dec 2004 19:29:12 -0500, "sel1"
wrote:

re your comment on over torquing, the nuts are pretty small (3/8) and I
could easily see that happening but Jim has me thinking more of rot (wet or
dry) than I care to now. The transom is about 12' X 3.5' and the plywood
core is at least 2" thick. Yikes! $$$$


The last time I checked, which was about two months ago, a 4'X8'X1"
sheet of fir marine plywood was right about $160 a sheet.. If you
thump out the suspect area, you may find that the you will be able to
scab in plywood and make the transom as strong as it ever was.

The other way to tell how bad the wood might be is to beg. borrow or
steal a moisture meter and check it that way.

In either case you may not wish to use a backing plate, in particular
if a large area is rotten. It's only going to create more stress on
the transom.

It's a tough one.

Later,

Tom

RichG December 13th 04 04:15 AM

I didn't say I haven't heard of it.

I don't know its density and strength relative to Corion or other molded
plastic flat stock.
--
RichG manager, Carolina Skiff Owners Group on MSN
http://groups.msn.com/CarolinaSkiffOwners
..
************************************************** *****************
"Short Wave Sportfishing" wrote in message
...
On Sun, 12 Dec 2004 23:41:28 GMT, "RichG"

I'm surprised you've never heard of it - it's used on fiberglass boats
for cabinet/storage/baitwell covers/doors and is the stuff used in
electronic boxes.

http://www.kingplastic.com/Products/...ardFamily.aspx

Later,

Tom




K. Smith December 13th 04 07:25 AM

sel1 wrote:
Thanks so much for the detail K, pretty straight forward. You say aluminum
is OK. As in not the best material?


If you're talking 3/8 bolts 1/4 should be OK but go to 3/8 if you have
reservations; or go to dinner:-).

Most of the work will be above the water line but my swim platform brackets
go below the water line and they are steel angle iron (probably home made).


Is it a trailer boat?? I thought it was a trailer boat but now I'm
wondering if it's a moored for the season type boat??? Getting wet while
being used is OK but if it's permanently in the water then stainless
might be better below the waterline.

Remember the stern drive or OB itself is make of aluminium & put
together with stainless bolts & what nots. They are wet whenever the
boat is in the water, even worse the top of the gearbox is blasted with
very hot exhaust driven salt water when the engine is running (they
always corrode from the inside the outside paint etc is just fluff for
the punters:-)), so your 1/4" plates are not such a worry really.

Any ideas on what kind of support system I could use so that the it doesn't
have to go below water line?


Lots of people have stainless cables, chains or even heavy stainless
rod (me:-)) from the top of the transom to the duck board (swim platform).


Either that or I switch to aluminum angle
pieces and stainless bolts. Aluminum should be OK below water line?


Again only if it's a trailer type boat that comes out of the water most
of the year, a few weeks at a time would be OK but full time???, creates
antifoul problems also because you need the aluminium suitable stuff
which doesn't work too well:-)

I notice below some comments about maybe the transom is rotten?? be
careful here because replacing the transom core is just as you suspect a
big job to do yourself or an expensive one to have done for you. If you
have no other symptoms than those you've detailed & just want to tidy up
a bit then new stainless bolts, properly installed is the go.

Hope you don't mind but I've pasted one of my previous howtos on
transom repairs below; just so you can get some better understanding of
what a really big job it is, most older boats have a low value because
the cost of repairing the transom is not worth the money or owner effort.

All the best.

K


Previous
owner didn't even use stainless bolts so they were really tough to get off.


Paste of transom howto;

I'm making some assumptions (again) but indeed it sounds like the
transom has failed, probably because the core was plywood & over time
has rotted.

It's a big job, but not too complex & even if you choose not to do it,
it might help to know what needs to be done.

The transom from the outside in is, fibreglass, plywood then
another layer of fibreglass. Sounds like the load from the motor has
actually broken the inner & outer skins along with the plywood
obviously. Have a really good look at it & you will see what
has happened, don't be shy about poking/drilling holes to be absolutely
sure it is a rotten transom, it might have hit something & not been
properly repaired, not likely but
be sure.

On the assumption it is the transom, to repair you need to strip all
the machinery off the stern of the boat, motor, steering, wiring, fuel
filters/lines etc. etc. also peel the rubbing/cover rubber off for a few
feet along the hull.

Using a 4in. grinder (wear goggles & dust mask) with a metal cutting
disc;

(i) you'll probably need to remove the outboard well, this will need to
be cut where the deck is bonded onto the hull (don't try to remove any
fastenings just cut them) & unfortunately you'll need to continue the
cuts along each gunwale until level with the forward end of the outboard
well, then across to deck into the inside, now the outboard
well should lift out,

(ii) cut all around the inside of the transom where it joins the hull,
but not too deep, you only want to remove the inner skin, (if the floor
goes all the way back, cut & remove enough out to give yourself plenty
of room)

(iii) now with hammers & chisels remove the transom inner skin (try not
to destroy it too much as you can use it as a template to cut the new
transom core later on), then continue chiseling getting all the old
plywood out, now with a metal grinding disc, completely grind the entire
area until there is no trace of the old wood or it's bonding
agent attached to the transom which you will be leaving in situ, grind
along the hull sides bottom etc for a good distance to give plenty of
fresh cleanly ground area to bond to, also tidy up around the gunwale
where you removed the O/B eng. well & under the well where it bonds to
the gunwale. (keep everything all dry & clean)

(iv) Find your local fibreglass supplier, commercial not a hardware
store or such & get your materials. You will need all that is mentioned
below, except the woven cloth should be heavy, at least 800 gsm, plus
you need a new core for the transom, there are new materials
now that are very strong, bond well, don't rot & are specifically
designed for transoms, your supplier can advise, but if you are stuck
use ply again, you'll need enough to make the core 2 in thick min, you
will also need some bonding agent, (a fair bit actually) use a brand
"probond" but be guided by your supplier.


(v) The repair is as follows;
(a) using the old inner transom as a template, cut the new core to the
correct shape,
(b) completely coat the inside of the old outer transom with catalysed
probond & the outer (stern) side of the new transom core, then place the
new core into the boat, drill some holes through where the old engine
mount bolts were & bolt pre-prepared timbers inside & out, to act as a
press to get the new core well bedding in against the old outer
transom & hull perimeter, if it doesn't look right, drill some more
holes & use more bolts/wood or whatever, you only have 15-20 mins & any
extra holes in the transom can be simply repaired later.
(c) after the probond has gone off, a final tidy up with the grinder,
you can glass a new inner transom in, being careful to ensure that each
layer is glassed to the old hull & not just the layer under it. (i.e.
each successive layer travels slightly, say 1.5in. further along the
hull) Inside there is no need to "finish" it off too much.
(d) using probond, as with the transom core, replace the outboard well &
put new fastenings into the deck shelf, where you had to cut across the
deck there will be a gap the thickness of the cutting disc, put some
small nuts & bolts with biggish washers on to align the two edges, under
the deck, put some glass between the bolts, later remove the bolts
(grind them out) & glass over the holes from underneath, this area is
more than cosmetic so don't skimp under the decks.
(e) the only "finishing" needed is the two small cuts across the deck,
the original holes left in the outer transom & any additional holes you
put in the transom to help draw the new core into place.
(f) in your travels if you come across any other rot or problem in the
boat, the repair is much the same & by this time it'll be a doddle for you.

Don't hesitate to ask, the NG or your fibreglass supplier if you have a
problem with what & how it's done, "before" you start:-)


To do it properly takes a little time but doesn't cost a single cent
more as in;

(i) Aluminium is OK say;
(a) 1/4"
(b) Size/shape of the backing is up to you, usually the available space
will dictate the shape size etc, the rule is; if it looks right it
probably is:-)
(b) it's not under water as such so dissimilar metals shouldn't be an
issue (even with stainless you'd still need to ensure the same stainless
as the bolts say 316 vs 3xx or it corrodes anyway:-)
(c) aluminium is much easier to work & you can even drill it in situ
from the outside if you have a tricky nook or cranny.

(ii) Chamfer just the outer perimeter of the plates away from where
they'll pull against the hull, if you leave a sharp edge it can cut into
the outer glass under load & leave a crack in the flow or gelcoat for
water to get in.

(iii) You should try to seal inside all the through hull holes:
(a) particularly if it's the cored transom
(b) Coat the holes right through with any of the good epoxy fillers, then
(c) push the bolts back in while it's wet, having given the bolt a good
coat of grease first (dipped in candle wax works too).
(d) Once epoxy has gelled you should be able to get your bolts back out
with a spanner, leaving a good protection for the transom core (usually
plywood) & a good fit for the bolt.

(iv) When ready to put it all together again;
(a) use plenty of any of the good sealants, sadly price is a good
indicator so any marine recommended 3M or marine sikaflex (German?? not
sure) is OK.
(b) Clean the hull, parts, holes, bolts etc with solvent so the sealant
can adhere.
(c) Put all the bolts in & tighten the nuts (don't turn the bolts if
you can avoid it, it messes up the sealant) just tight enough to get all
the parts mated & snug, don't over tighten at this stage,
(d) get rid of excess squeezed out sealant with whatever solvent.
(e) Let the whole thing set for a while at least a day but longer is
OK, so the sealant can fully cure.
(f) Now you can tighten it all up, but again make sure someone holds
the bolts so they can't turn & you just tighten the nuts.

It'll be ticketyboo:-)

K





Short Wave Sportfishing December 13th 04 11:10 AM

On Mon, 13 Dec 2004 04:15:57 GMT, "RichG"
wrote:

I didn't say I haven't heard of it.

I don't know its density and strength relative to Corion or other molded
plastic flat stock.


It's dense. I have a piece of 1" left over from a friends boat
project. Just for giggles, I sawed off a odd angled corner off and
shot it with a .32 Police Special - stopped the bullet cold.

Won't stop anything bigger though. :)

On both my boats, StarBoard is used in a ton of different places - all
the Ranger hatches are made out of the stuff. I'm a big guy and when
I stand on the front casting platform, no flex, no nothing.

Later,

Tom

Lloyd Sumpter December 13th 04 03:16 PM

On Sun, 12 Dec 2004 19:29:12 -0500, sel1 wrote:

Tom,

re your comment on over torquing, the nuts are pretty small (3/8) and I
could easily see that happening but Jim has me thinking more of rot (wet or
dry) than I care to now. The transom is about 12' X 3.5' and the plywood
core is at least 2" thick. Yikes! $$$$


Yep, any hint of "rot" and the "OhMyGod your transom is Totally Rotten and
Has To Be Replaced!" fearmongers gather like moths to a light.

The Truth is, most older boats have SOME rot or at least punky spots in
the transom. Another Truth is that the transom as to be REALLY REALLY
rotten (ie obvious) before it's dangerous (ie likely for catastrophic
failure).

I'm guessing your transom is fine. Check for cracking around the outboard
mounts or outdrive: if there are no obvious cracks, you're ok.

As for the overtorqued nuts, you MIGHT want to goop in some penetrating
epoxy like CPES (www.rotdoctor.com), or just "line" the holes with epoxy
to prevent moisure from getting to the wood. Then Back with SS or
Starboard (I don't like backing with aluminum - too soft!)

Lloyd Sumpter
"Far Cove" Catalina 36


Short Wave Sportfishing December 13th 04 05:03 PM

On Mon, 13 Dec 2004 07:16:03 -0800, Lloyd Sumpter
wrote:

On Sun, 12 Dec 2004 19:29:12 -0500, sel1 wrote:

Tom,

re your comment on over torquing, the nuts are pretty small (3/8) and I
could easily see that happening but Jim has me thinking more of rot (wet or
dry) than I care to now. The transom is about 12' X 3.5' and the plywood
core is at least 2" thick. Yikes! $$$$


Yep, any hint of "rot" and the "OhMyGod your transom is Totally Rotten and
Has To Be Replaced!" fearmongers gather like moths to a light.

The Truth is, most older boats have SOME rot or at least punky spots in
the transom. Another Truth is that the transom as to be REALLY REALLY
rotten (ie obvious) before it's dangerous (ie likely for catastrophic
failure).

I'm guessing your transom is fine. Check for cracking around the outboard
mounts or outdrive: if there are no obvious cracks, you're ok.

As for the overtorqued nuts, you MIGHT want to goop in some penetrating
epoxy like CPES (www.rotdoctor.com), or just "line" the holes with epoxy
to prevent moisure from getting to the wood. Then Back with SS or
Starboard (I don't like backing with aluminum - too soft!)


I'm in the "suspect until proven good" category on this one. It also
depends on the type of transom. There's more than just rotten wood to
consider.

I do agree that huge areas of rot are unlikely, but I have seen on
more boats than just one, how water can travel along wood including
plywoods.

However, a good thump test and use of a moisture meter can tell right
quick.

Later,

Tom

sel1 December 14th 04 12:24 AM

Lloyd,

I have outdrives and there is no cracking in the glass at all. Grazing on
other parts of the boat but nothing on the transom.

I can see that this topic is resulting in a hung jury. I will certainly do
as Tom suggests and tap away but I will likely end up being at the mercy of
another surveyor or the "repair man". The original surveyor has passed away
so I can't probe him for details.

Steve

Yep, any hint of "rot" and the "OhMyGod your transom is Totally Rotten and
Has To Be Replaced!" fearmongers gather like moths to a light.

The Truth is, most older boats have SOME rot or at least punky spots in
the transom. Another Truth is that the transom as to be REALLY REALLY
rotten (ie obvious) before it's dangerous (ie likely for catastrophic
failure).

I'm guessing your transom is fine. Check for cracking around the outboard
mounts or outdrive: if there are no obvious cracks, you're ok.

As for the overtorqued nuts, you MIGHT want to goop in some penetrating
epoxy like CPES (www.rotdoctor.com), or just "line" the holes with epoxy
to prevent moisure from getting to the wood. Then Back with SS or
Starboard (I don't like backing with aluminum - too soft!)

Lloyd Sumpter
"Far Cove" Catalina 36




Short Wave Sportfishing December 14th 04 01:07 AM

On Mon, 13 Dec 2004 19:24:59 -0500, "sel1"
wrote:

Lloyd,

I have outdrives and there is no cracking in the glass at all. Grazing on
other parts of the boat but nothing on the transom.

I can see that this topic is resulting in a hung jury. I will certainly do
as Tom suggests and tap away but I will likely end up being at the mercy of
another surveyor or the "repair man". The original surveyor has passed away
so I can't probe him for details.


Out of curiosity, how old is the previous survey? That should give
you a good starting point to do a self-inspection.

Chuck and Loyld make some good points - there are some things that are
not necessarily the death knell for the boat.

In this case, it wouldn't hurt to reassure yourself that there isn't a
problem in that particular area.

Later,

Tom

sel1 December 14th 04 01:07 AM

Is it a trailer boat?? ...

It is a 1969 40' fiberglass hull houseboat (no groans now). You are are
probably wondering if I'm crazy and if it's worth it. I paid 4k for the boat
so there is room for some investment (and I use the word loosely).

Remember the stern drive or OB itself is make of aluminium & put
together with stainless bolts & what nots. They are wet whenever the
boat is in the water, even worse the top of the gearbox is blasted with
very hot exhaust driven salt water when the engine is running (they
always corrode from the inside the outside paint etc is just fluff for
the punters:-)), so your 1/4" plates are not such a worry really.


Good point. I'm thinking aluminum because it is so much easier to work with.

Lots of people have stainless cables, chains or even heavy stainless
rod (me:-)) from the top of the transom to the duck board (swim platform).


I had thought of this but not having been around a lot of boats yet, I have
yet to see one supported this way and thought maybe it wasn't a sound way to
support the platform. I would assume you just bolt angle iron or similar to
the transom along the length of the platform to rest it on (bolted of
course)

Either that or I switch to aluminum angle
pieces and stainless bolts. Aluminum should be OK below water line?


Again only if it's a trailer type boat that comes out of the water most
of the year, a few weeks at a time would be OK but full time???, creates
antifoul problems also because you need the aluminium suitable stuff
which doesn't work too well:-)

I notice below some comments about maybe the transom is rotten?? be
careful here because replacing the transom core is just as you suspect a
big job to do yourself or an expensive one to have done for you. If you
have no other symptoms than those you've detailed & just want to tidy up
a bit then new stainless bolts, properly installed is the go.


I didn't pay much for the boat but it is old so of course I don't want to
spend my savings all on the transom.

Hope you don't mind but I've pasted one of my previous howtos on
transom repairs below; just so you can get some better understanding of
what a really big job it is, most older boats have a low value because
the cost of repairing the transom is not worth the money or owner effort.


Your how to is much appreciated Kay(?). I also pick up some West System
manuals. I will now just hope the transom core is just mostly wet.

Thanks again




sel1 December 14th 04 01:17 AM

Tom, I just purchased it early fall. If the previous owner had it surveyed
(I never even thought to ask if it was, but it was insured so it must have
been.) that would have been 4 years ago. Do these surveys get registered
anywhere so I could confirm this? The owners were so sure that the boat
would pass with flying colors, they felt bad and they dropped their price by
just over half when I told them what the surveyor said about a wet transom
(and some minor things in comparison), or maybe that was their plan if he
spotted it? Who knows.

"Short Wave Sportfishing" wrote in message
...
On Mon, 13 Dec 2004 19:24:59 -0500, "sel1"
wrote:

Out of curiosity, how old is the previous survey? That should give
you a good starting point to do a self-inspection.

Chuck and Loyld make some good points - there are some things that are
not necessarily the death knell for the boat.

In this case, it wouldn't hurt to reassure yourself that there isn't a
problem in that particular area.

Later,

Tom




K. Smith December 14th 04 08:10 AM

sel1 wrote:
Is it a trailer boat?? ...



It is a 1969 40' fiberglass hull houseboat (no groans now). You are are
probably wondering if I'm crazy and if it's worth it. I paid 4k for the boat
so there is room for some investment (and I use the word loosely).


Cheap enough well done.


Remember the stern drive or OB itself is make of aluminium & put
together with stainless bolts & what nots. They are wet whenever the
boat is in the water, even worse the top of the gearbox is blasted with
very hot exhaust driven salt water when the engine is running (they
always corrode from the inside the outside paint etc is just fluff for
the punters:-)), so your 1/4" plates are not such a worry really.



Good point. I'm thinking aluminum because it is so much easier to work with.


Lots of people have stainless cables, chains or even heavy stainless
rod (me:-)) from the top of the transom to the duck board (swim platform).



I had thought of this but not having been around a lot of boats yet, I have
yet to see one supported this way and thought maybe it wasn't a sound way to
support the platform. I would assume you just bolt angle iron or similar to
the transom along the length of the platform to rest it on (bolted of
course)


Usually you have a hefty timber bolted across the transom where you
want the duck board to go, in this case you can made it go right across
& bolt it on with backing plates etc so it will also toughen up an older
transom a bit anyway.

Then using large stainless (or brass they're out of the water) hinges
you hinge the board to that timber. A couple of padeyes atop the transom
(close to the deck, backing places etc) & the same at the corners of the
duck board. You can pull it up against the stern when you want to get
close in stern first etc.



Either that or I switch to aluminum angle

pieces and stainless bolts. Aluminum should be OK below water line?


Again only if it's a trailer type boat that comes out of the water most
of the year, a few weeks at a time would be OK but full time???, creates
antifoul problems also because you need the aluminium suitable stuff
which doesn't work too well:-)

I notice below some comments about maybe the transom is rotten?? be
careful here because replacing the transom core is just as you suspect a
big job to do yourself or an expensive one to have done for you. If you
have no other symptoms than those you've detailed & just want to tidy up
a bit then new stainless bolts, properly installed is the go.



I didn't pay much for the boat but it is old so of course I don't want to
spend my savings all on the transom.


Don't be too worried about it; as I think it was Lloyd said, not many
older boats wouldn't have a bit of rot here & there. If you see obvious
signs of it flexing about under stress or delamination from the core
then consider some strengthening maybe before you go ripping the transom
to bits.


Hope you don't mind but I've pasted one of my previous howtos on
transom repairs below; just so you can get some better understanding of
what a really big job it is, most older boats have a low value because
the cost of repairing the transom is not worth the money or owner effort.



Your how to is much appreciated Kay(?). I also pick up some West System
manuals. I will now just hope the transom core is just mostly wet.


Enjoy it!!! at that price it's hard not to of course:-)

K

Thanks again





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