Low transoms and cockpit drains
 

I dont want to cause a ruckus on this obviously touchy topic, but why
are some boats meant to be used offshore have low transoms? Is it bad
design or is there really a reason? On sailboats, so-called "sugar
scoop" transoms are popular on some modern boats with the reasoning
that it enables the cockpit to drain. This requires a seriously high
bridge deck into the cabin and I simply would not trust such a thing
offshore. I will admit my sailboat cockpit drains are too small.
On the subject of cockpit drains for powerboats, should one put more
effort in keeping water out or in draining the cockpit once it is in?
Currently, I have no large drain in my Tolman but am installing the
largest bilge pump I can find (3500 gph). I also have no decking
installed because I want to be able to see my hull and how much water
I have accumulated.

Low transoms and cockpit drains
 

Low transoms and cockpit drains
 

On Aug 17, 4:06 pm, hk wrote:
wrote:
I dont want to cause a ruckus on this obviously touchy topic, but why
are some boats meant to be used offshore have low transoms? Is it bad
design or is there really a reason? On sailboats, so-called "sugar
scoop" transoms are popular on some modern boats with the reasoning
that it enables the cockpit to drain. This requires a seriously high
bridge deck into the cabin and I simply would not trust such a thing
offshore. I will admit my sailboat cockpit drains are too small.
On the subject of cockpit drains for powerboats, should one put more
effort in keeping water out or in draining the cockpit once it is in?
Currently, I have no large drain in my Tolman but am installing the
largest bilge pump I can find (3500 gph). I also have no decking
installed because I want to be able to see my hull and how much water
I have accumulated.

This is really funny. My "low transom" boat has a transom that is 25" at
its lowest point, and 36" outside of the motor notch. The 25" measure is
the standard for most single engine outboard boats that are not strictly
for inshore use.

A better question would be, why would those with boats with 25" transoms
and itty bitty motor wells think that one a large wave filled that well,
the water wouldn't keep coming aboard.

The transom cut-out on my boat will allow a hull partially filled with a
significant amount of water to drain.

Of course, you'd have to see the hull to appreciate its size and height.
SW Tom's 20-something Ranger would fit inside my 21' Parker, and, except
for the center console, would disappear.

Would it be the Size (volume) or height of the drywell that was most
important, I'd expect height to be most important. If ones boat is
filled by a following sea, will it drain fast enough to keep the next
one out?

Low transoms and cockpit drains
 

On Aug 17, 4:06*pm, hk wrote:
wrote:
I dont want to cause a ruckus on this obviously touchy topic, but why
are some boats meant to be used offshore have low transoms? *Is it bad
design or is there really a reason? *On sailboats, so-called "sugar
scoop" transoms are popular on some modern boats with the reasoning
that it enables the cockpit to drain. *This requires a seriously high
bridge deck into the cabin and I simply would not trust such a thing
offshore. *I will admit my sailboat cockpit drains are too small.
On the subject of cockpit drains for powerboats, should one put more
effort in keeping water out or in draining the cockpit once it is in?
Currently, I have no large drain in my Tolman but am installing the
largest bilge pump I can find (3500 gph). *I also have no decking
installed because I want to be able to see my hull and how much water
I have accumulated.

This is really funny. My "low transom" boat has a transom that is 25" at
its lowest point, and 36" outside of the motor notch. The 25" measure is
the standard for most single engine outboard boats that are not strictly
for inshore use.

A better question would be, why would those with boats with 25" transoms
and itty bitty motor wells think that one a large wave filled that well,
the water wouldn't keep coming aboard.

The transom cut-out on my boat will allow a hull partially filled with a
significant amount of water to drain.

Of course, you'd have to see the hull to appreciate its size and height.
SW Tom's 20-something Ranger would fit inside my 21' Parker, and, except
for the center console, would disappear.

Of course! We all know that anything you own, anything you think you
own, any dream of a family (Dr. Dr. wife) any thing you think, is FAR
superior to anything anybody else has, or thinks.

Which by the way, leads me to a point. Remember when you told someone
that you'd take an IQ test with them any time? Remember when I said
I'd LOVE to take you up on that challenge? Ready??

Low transoms and cockpit drains
 

Low transoms and cockpit drains
 

On Aug 17, 4:20 pm, hk wrote:
wrote:
On Aug 17, 4:06 pm, hk wrote:
wrote:
I dont want to cause a ruckus on this obviously touchy topic, but why
are some boats meant to be used offshore have low transoms? Is it bad
design or is there really a reason? On sailboats, so-called "sugar
scoop" transoms are popular on some modern boats with the reasoning
that it enables the cockpit to drain. This requires a seriously high
bridge deck into the cabin and I simply would not trust such a thing
offshore. I will admit my sailboat cockpit drains are too small.
On the subject of cockpit drains for powerboats, should one put more
effort in keeping water out or in draining the cockpit once it is in?
Currently, I have no large drain in my Tolman but am installing the
largest bilge pump I can find (3500 gph). I also have no decking
installed because I want to be able to see my hull and how much water
I have accumulated.
This is really funny. My "low transom" boat has a transom that is 25" at
its lowest point, and 36" outside of the motor notch. The 25" measure is
the standard for most single engine outboard boats that are not strictly
for inshore use.

A better question would be, why would those with boats with 25" transoms
and itty bitty motor wells think that one a large wave filled that well,
the water wouldn't keep coming aboard.

The transom cut-out on my boat will allow a hull partially filled with a
significant amount of water to drain.

Of course, you'd have to see the hull to appreciate its size and height.
SW Tom's 20-something Ranger would fit inside my 21' Parker, and, except
for the center console, would disappear.

Would it be the Size (volume) or height of the drywell that was most
important, I'd expect height to be most important. If ones boat is
filled by a following sea, will it drain fast enough to keep the next
one out?

Most of the motor wells on smaller outboard boats are not very deep or
wide, and will only hold a couple of gallons of water. Worse, they
usually are built into a rear seat or storage area of some sort that,
once the water goes over it, fills up the boat and prevents it from
flowing back out over the transom. Typically, these boats also have very
small scuppers.

I've been running small outboard boats for more than 50 years, and I
mean small, including some with 12" or 15" transoms. Virtually all my
boating has been in the ocean, Long Island Sound or, these days,
Chesapeake Bay. I have taken waves over the transom over the years,
including repeated waves. I survived and so did the boat. The worst I
have taken, though have been big waves over the bow that half filled the
boat. By gunning the engine, I was able to get most of the water out
almost immediately over the transom.

Wouldnt a large volume dry well be a problem because it would fill
with water and not drain fast enough? In fact, my dry well runs the
full width of the transom and I am considering filling the two ends
with foam if I take her to Bimini. I did increase the scupper
diameter but I think I should have made them even bigger.

Low transoms and cockpit drains
 

On Aug 17, 4:45 pm, wrote:
On Aug 17, 4:20 pm, hk wrote:



wrote:
On Aug 17, 4:06 pm, hk wrote:
wrote:
I dont want to cause a ruckus on this obviously touchy topic, but why
are some boats meant to be used offshore have low transoms? Is it bad
design or is there really a reason? On sailboats, so-called "sugar
scoop" transoms are popular on some modern boats with the reasoning
that it enables the cockpit to drain. This requires a seriously high
bridge deck into the cabin and I simply would not trust such a thing
offshore. I will admit my sailboat cockpit drains are too small.
On the subject of cockpit drains for powerboats, should one put more
effort in keeping water out or in draining the cockpit once it is in?
Currently, I have no large drain in my Tolman but am installing the
largest bilge pump I can find (3500 gph). I also have no decking
installed because I want to be able to see my hull and how much water
I have accumulated.
This is really funny. My "low transom" boat has a transom that is 25" at
its lowest point, and 36" outside of the motor notch. The 25" measure is
the standard for most single engine outboard boats that are not strictly
for inshore use.

A better question would be, why would those with boats with 25" transoms
and itty bitty motor wells think that one a large wave filled that well,
the water wouldn't keep coming aboard.

The transom cut-out on my boat will allow a hull partially filled with a
significant amount of water to drain.

Of course, you'd have to see the hull to appreciate its size and height.
SW Tom's 20-something Ranger would fit inside my 21' Parker, and, except
for the center console, would disappear.

Would it be the Size (volume) or height of the drywell that was most
important, I'd expect height to be most important. If ones boat is
filled by a following sea, will it drain fast enough to keep the next
one out?

Most of the motor wells on smaller outboard boats are not very deep or
wide, and will only hold a couple of gallons of water. Worse, they
usually are built into a rear seat or storage area of some sort that,
once the water goes over it, fills up the boat and prevents it from
flowing back out over the transom. Typically, these boats also have very
small scuppers.

I've been running small outboard boats for more than 50 years, and I
mean small, including some with 12" or 15" transoms. Virtually all my
boating has been in the ocean, Long Island Sound or, these days,
Chesapeake Bay. I have taken waves over the transom over the years,
including repeated waves. I survived and so did the boat. The worst I
have taken, though have been big waves over the bow that half filled the
boat. By gunning the engine, I was able to get most of the water out
almost immediately over the transom.

Wouldnt a large volume dry well be a problem because it would fill
with water and not drain fast enough? In fact, my dry well runs the
full width of the transom and I am considering filling the two ends
with foam if I take her to Bimini. I did increase the scupper
diameter but I think I should have made them even bigger.

I believe that statistics bear me out when it comes to boats sinking
due to waves over the transom. All you have to do is look at BOAT-US
statistics. It seems to happen a lot.

Low transoms and cockpit drains
 

On Sun, 17 Aug 2008 12:06:05 -0700 (PDT),
wrote:

I dont want to cause a ruckus on this obviously touchy topic, but why
are some boats meant to be used offshore have low transoms? Is it bad
design or is there really a reason? On sailboats, so-called "sugar
scoop" transoms are popular on some modern boats with the reasoning
that it enables the cockpit to drain. This requires a seriously high
bridge deck into the cabin and I simply would not trust such a thing
offshore. I will admit my sailboat cockpit drains are too small.
On the subject of cockpit drains for powerboats, should one put more
effort in keeping water out or in draining the cockpit once it is in?
Currently, I have no large drain in my Tolman but am installing the
largest bilge pump I can find (3500 gph). I also have no decking
installed because I want to be able to see my hull and how much water
I have accumulated.

The Tolmans look to be nice boats.
Note the transom on this Jumbo.
http://www.fishyfish.com/bobbruce/index.html
A simple answer to your questions would be to e-mail these diveboat
guys. I'm thinking they take the boat offshore.
I did a little reading about the glue-and-stitch process, and far as I
can tell if properly done such boats are as strong or stronger than
any other method.
Seems to me that the stitch and glue method used to build monocoque
hulls can be incorporated with additional framing either during or
after the hull construction, and some of pics I've seen of Tolmans
seem to show interior framing that probably wasn't in the original
specs.
How much does your Tolman weigh and have you ever checked
gas consumption? If I was a bit younger I would really consider
building one.

--Vic

Low transoms and cockpit drains
 

On Aug 17, 5:00 pm, Vic Smith wrote:
On Sun, 17 Aug 2008 12:06:05 -0700 (PDT),
wrote:

I dont want to cause a ruckus on this obviously touchy topic, but why
are some boats meant to be used offshore have low transoms? Is it bad
design or is there really a reason? On sailboats, so-called "sugar
scoop" transoms are popular on some modern boats with the reasoning
that it enables the cockpit to drain. This requires a seriously high
bridge deck into the cabin and I simply would not trust such a thing
offshore. I will admit my sailboat cockpit drains are too small.
On the subject of cockpit drains for powerboats, should one put more
effort in keeping water out or in draining the cockpit once it is in?
Currently, I have no large drain in my Tolman but am installing the
largest bilge pump I can find (3500 gph). I also have no decking
installed because I want to be able to see my hull and how much water
I have accumulated.

The Tolmans look to be nice boats.
Note the transom on this Jumbo.http://www.fishyfish.com/bobbruce/index.html
A simple answer to your questions would be to e-mail these diveboat
guys. I'm thinking they take the boat offshore.
I did a little reading about the glue-and-stitch process, and far as I
can tell if properly done such boats are as strong or stronger than
any other method.
Seems to me that the stitch and glue method used to build monocoque
hulls can be incorporated with additional framing either during or
after the hull construction, and some of pics I've seen of Tolmans
seem to show interior framing that probably wasn't in the original
specs.
How much does your Tolman weigh and have you ever checked
gas consumption? If I was a bit younger I would really consider
building one.

--Vic

Mine is a 20' Standard so weighs less than the Jumbo. I remember some
controversy when those guys wee building over the severe cut-away
transom for use as a dive boat. My 20' seems to weigh very little but
I am not really sure. SHe does get pushed around by waves but I
cannot compare to anything else except an 8000 lb sailboat. Fuel
economy is roughly 4-4.5 mpg with 6 people aboard using a 90 hp 2cycle
Yamaha. I used the 90 hp rather than the smaller engine Tolman reccs
because I knew I would always have about 5 ppl aboard.

Low transoms and cockpit drains