RE: [bolger] TOPAZ SEA TRIAL
Way to go Brad. Sounds absolutely delightful!
Les
-----Original Message-----
From: bradford raby [mailto:sailormon@...]
Sent: Monday, June 12, 2000 7:53 AM
To:bolger@egroups.com
Subject: [bolger] TOPAZ SEA TRIAL
This update to Les, Tim, Chuck,P and S as well as any who have an interest
in performance under power.
After adjusting the RPM of the engine yesterday we took her for a ride.
The inside cluttered with parts and tools. I took along a couple of
neighbors in their 70's plus my wife. The first couple of miles are on a
river with some stumps and shallows to be avoided which leads from my home
to a long series of lakes to the north. As the river twists and turns we
kept the speed down and got to try her at hull speed first. None of the
instruments were connected at this point so I can only estimate speed.
However the minimum at idle with the 75 seems to be about 4-5 knots. A
fast idles really gets it going at 7-9. Of note is the lack of wake. The
river was smooth after our passage.
Once out on the open water, we gradually increased speed and without going
on a plane there was still a minimum of wake but a great increase in speed.
Going from displacement to a plane seemed to occur without a transition.
In other words you had to look out to determine if in fact you were there,
this without full throttle. Pushing the throttle foreword really got
exciting as the boat was going down wind and it got into a speed range I
could not estimate and I would not hold it to the highest RPM as we were
really cooking then. I backed it off to about 3/4 and felt we were
skipping over the small waves. My passengers could feel the bottom
impacting all the way back.
I think the speed is going to exceed that predicted by the designer and
could have been done with a 50 hp, at least a plane. Only speculating of
course.
For traveling longer distances, my wife and I are more content to go at
fast hull speeds which the Topaz really does well.
As to the cut out, it does as I predicted. It really does relieve some of
the turbulence which would have occurred inside the constriction of the
hull. At higher speeds, there is still considerable splashing within this
area, but restricted to aft of the motor. My friend suggested cutting the
rest of the hull below water up to the transom. My feeling is that this
curving in contributes to the lack of wake and efficiency of the hull and
needs to be there. If the minor splashing were a problem, an easy fix
could be made. Putting up a ninety degree wall on the back of the transom
which blended into the curved part of the hull on each side would work
well. I will try this with some scrap foam out of curiosity. I found that
turning needed to be planned, Being a long hull with a deep cutwater makes
the boat pivot at the nose. I am used to pivoting in the middle because of
my keel. I suppose this is the nature of this type of boat and is no
problem as long as a person is aware of it. My overall impression is that
this is going to be one hell of a fun boat. The bow rides high and light
and should take waves comfortably. It track straight and does not wander
even with hands off the wheel. She is fast if you want that. At slow
speeds, the comfort is great. Best of all is the elegance of getting
there. My passengers were sitting down and enjoying the view, both from
the foredeck and the settees. From a macho point of view, it will be fun
going slow and still keeping up with the fast guys now and then. Brad
------------------------------------------------------------------------
Buy Long Distance with your GROUP and SAVE!!!
http://click.egroups.com/1/4123/10/_/3457/_/960814726/
------------------------------------------------------------------------
Les
-----Original Message-----
From: bradford raby [mailto:sailormon@...]
Sent: Monday, June 12, 2000 7:53 AM
To:bolger@egroups.com
Subject: [bolger] TOPAZ SEA TRIAL
This update to Les, Tim, Chuck,P and S as well as any who have an interest
in performance under power.
After adjusting the RPM of the engine yesterday we took her for a ride.
The inside cluttered with parts and tools. I took along a couple of
neighbors in their 70's plus my wife. The first couple of miles are on a
river with some stumps and shallows to be avoided which leads from my home
to a long series of lakes to the north. As the river twists and turns we
kept the speed down and got to try her at hull speed first. None of the
instruments were connected at this point so I can only estimate speed.
However the minimum at idle with the 75 seems to be about 4-5 knots. A
fast idles really gets it going at 7-9. Of note is the lack of wake. The
river was smooth after our passage.
Once out on the open water, we gradually increased speed and without going
on a plane there was still a minimum of wake but a great increase in speed.
Going from displacement to a plane seemed to occur without a transition.
In other words you had to look out to determine if in fact you were there,
this without full throttle. Pushing the throttle foreword really got
exciting as the boat was going down wind and it got into a speed range I
could not estimate and I would not hold it to the highest RPM as we were
really cooking then. I backed it off to about 3/4 and felt we were
skipping over the small waves. My passengers could feel the bottom
impacting all the way back.
I think the speed is going to exceed that predicted by the designer and
could have been done with a 50 hp, at least a plane. Only speculating of
course.
For traveling longer distances, my wife and I are more content to go at
fast hull speeds which the Topaz really does well.
As to the cut out, it does as I predicted. It really does relieve some of
the turbulence which would have occurred inside the constriction of the
hull. At higher speeds, there is still considerable splashing within this
area, but restricted to aft of the motor. My friend suggested cutting the
rest of the hull below water up to the transom. My feeling is that this
curving in contributes to the lack of wake and efficiency of the hull and
needs to be there. If the minor splashing were a problem, an easy fix
could be made. Putting up a ninety degree wall on the back of the transom
which blended into the curved part of the hull on each side would work
well. I will try this with some scrap foam out of curiosity. I found that
turning needed to be planned, Being a long hull with a deep cutwater makes
the boat pivot at the nose. I am used to pivoting in the middle because of
my keel. I suppose this is the nature of this type of boat and is no
problem as long as a person is aware of it. My overall impression is that
this is going to be one hell of a fun boat. The bow rides high and light
and should take waves comfortably. It track straight and does not wander
even with hands off the wheel. She is fast if you want that. At slow
speeds, the comfort is great. Best of all is the elegance of getting
there. My passengers were sitting down and enjoying the view, both from
the foredeck and the settees. From a macho point of view, it will be fun
going slow and still keeping up with the fast guys now and then. Brad
------------------------------------------------------------------------
Buy Long Distance with your GROUP and SAVE!!!
http://click.egroups.com/1/4123/10/_/3457/_/960814726/
------------------------------------------------------------------------
This update to Les, Tim, Chuck,P and S as well as any who have an interest
in performance under power.
After adjusting the RPM of the engine yesterday we took her for a ride.
The inside cluttered with parts and tools. I took along a couple of
neighbors in their 70's plus my wife. The first couple of miles are on a
river with some stumps and shallows to be avoided which leads from my home
to a long series of lakes to the north. As the river twists and turns we
kept the speed down and got to try her at hull speed first. None of the
instruments were connected at this point so I can only estimate speed.
However the minimum at idle with the 75 seems to be about 4-5 knots. A
fast idles really gets it going at 7-9. Of note is the lack of wake. The
river was smooth after our passage.
Once out on the open water, we gradually increased speed and without going
on a plane there was still a minimum of wake but a great increase in speed.
Going from displacement to a plane seemed to occur without a transition.
In other words you had to look out to determine if in fact you were there,
this without full throttle. Pushing the throttle foreword really got
exciting as the boat was going down wind and it got into a speed range I
could not estimate and I would not hold it to the highest RPM as we were
really cooking then. I backed it off to about 3/4 and felt we were
skipping over the small waves. My passengers could feel the bottom
impacting all the way back.
I think the speed is going to exceed that predicted by the designer and
could have been done with a 50 hp, at least a plane. Only speculating of
course.
For traveling longer distances, my wife and I are more content to go at
fast hull speeds which the Topaz really does well.
As to the cut out, it does as I predicted. It really does relieve some of
the turbulence which would have occurred inside the constriction of the
hull. At higher speeds, there is still considerable splashing within this
area, but restricted to aft of the motor. My friend suggested cutting the
rest of the hull below water up to the transom. My feeling is that this
curving in contributes to the lack of wake and efficiency of the hull and
needs to be there. If the minor splashing were a problem, an easy fix
could be made. Putting up a ninety degree wall on the back of the transom
which blended into the curved part of the hull on each side would work
well. I will try this with some scrap foam out of curiosity. I found that
turning needed to be planned, Being a long hull with a deep cutwater makes
the boat pivot at the nose. I am used to pivoting in the middle because of
my keel. I suppose this is the nature of this type of boat and is no
problem as long as a person is aware of it. My overall impression is that
this is going to be one hell of a fun boat. The bow rides high and light
and should take waves comfortably. It track straight and does not wander
even with hands off the wheel. She is fast if you want that. At slow
speeds, the comfort is great. Best of all is the elegance of getting
there. My passengers were sitting down and enjoying the view, both from
the foredeck and the settees. From a macho point of view, it will be fun
going slow and still keeping up with the fast guys now and then. Brad
in performance under power.
After adjusting the RPM of the engine yesterday we took her for a ride.
The inside cluttered with parts and tools. I took along a couple of
neighbors in their 70's plus my wife. The first couple of miles are on a
river with some stumps and shallows to be avoided which leads from my home
to a long series of lakes to the north. As the river twists and turns we
kept the speed down and got to try her at hull speed first. None of the
instruments were connected at this point so I can only estimate speed.
However the minimum at idle with the 75 seems to be about 4-5 knots. A
fast idles really gets it going at 7-9. Of note is the lack of wake. The
river was smooth after our passage.
Once out on the open water, we gradually increased speed and without going
on a plane there was still a minimum of wake but a great increase in speed.
Going from displacement to a plane seemed to occur without a transition.
In other words you had to look out to determine if in fact you were there,
this without full throttle. Pushing the throttle foreword really got
exciting as the boat was going down wind and it got into a speed range I
could not estimate and I would not hold it to the highest RPM as we were
really cooking then. I backed it off to about 3/4 and felt we were
skipping over the small waves. My passengers could feel the bottom
impacting all the way back.
I think the speed is going to exceed that predicted by the designer and
could have been done with a 50 hp, at least a plane. Only speculating of
course.
For traveling longer distances, my wife and I are more content to go at
fast hull speeds which the Topaz really does well.
As to the cut out, it does as I predicted. It really does relieve some of
the turbulence which would have occurred inside the constriction of the
hull. At higher speeds, there is still considerable splashing within this
area, but restricted to aft of the motor. My friend suggested cutting the
rest of the hull below water up to the transom. My feeling is that this
curving in contributes to the lack of wake and efficiency of the hull and
needs to be there. If the minor splashing were a problem, an easy fix
could be made. Putting up a ninety degree wall on the back of the transom
which blended into the curved part of the hull on each side would work
well. I will try this with some scrap foam out of curiosity. I found that
turning needed to be planned, Being a long hull with a deep cutwater makes
the boat pivot at the nose. I am used to pivoting in the middle because of
my keel. I suppose this is the nature of this type of boat and is no
problem as long as a person is aware of it. My overall impression is that
this is going to be one hell of a fun boat. The bow rides high and light
and should take waves comfortably. It track straight and does not wander
even with hands off the wheel. She is fast if you want that. At slow
speeds, the comfort is great. Best of all is the elegance of getting
there. My passengers were sitting down and enjoying the view, both from
the foredeck and the settees. From a macho point of view, it will be fun
going slow and still keeping up with the fast guys now and then. Brad