On Fri, 12 Nov 2010 11:21:39 -0500, "Flying Pig"
wrote:

Nice pix.

I'd be worried, however, about all the washers for depth. Not possible to
build in a bend to the tightening arm to bring it flush to the alternator?

It's possible but I'd need to disassemble part of the heat exchanger
to remove the adjusment arm, bend it and reinstall. What I've done
since the pictures were taken is to replace the washer stack with a
solid steel spacer. I've also replaced the original bolt with one
that is longer so that it now projects all the way through the
adjusment tab on the alternator, backed up by a grade 8 steel washer,
lock washer and nut. The whole assembly is extremely rigid with no
hint of vibration or flexing.

On Nov 23, 12:24*am, I am Tosk
wrote:
In article ,
says...







On Fri, 12 Nov 2010 11:21:39 -0500, "Flying Pig"
wrote:

Nice pix.

I'd be worried, however, about all the washers for depth. *Not possible to
build in a bend to the tightening arm to bring it flush to the alternator?

It's possible but I'd need to disassemble part of the heat exchanger
to remove the adjusment arm, bend it and reinstall. *What I've done
since the pictures were taken is to replace the washer stack with a
solid steel spacer. * I've also replaced the original bolt with one
that is longer so that it now projects all the way through the
adjusment tab on the alternator, backed up by a grade 8 steel washer,
lock washer and nut. * The whole assembly is extremely rigid with no
hint of vibration or flexing.

Sounds like a better solution, of course keep an eye on it and I would
carry an extra bolt and spacer, washer, etc... Just in case.

--
Rowdy Mouse Racing - Pain is temporary, Glory is forever!- Hide quoted text -

- Show quoted text -

It's not the bolt that will go. If it fails it will be the tongue on
the alternator case that breaks. I have to agree that it looks like
it would be ok though. A couple bends in the arm would be perfect but
if you have to do a bunch of disassembly to get the arm off I can see
wanting to avoid that. Looks like there is too much other stuff in
there to heat and bend the arm in place.

On Tue, 23 Nov 2010 10:04:30 -0800 (PST), jamesgangnc
wrote:

Looks like there is too much other stuff in
there to heat and bend the arm in place.

Yes and the bends need to be done accurately to ensure that everything
lines up when you're done. It really needs to be in a vice to bend it
properly.

"Wayne.B" wrote in message
news
On Fri, 12 Nov 2010 11:21:39 -0500, "Flying Pig"
wrote:

Nice pix.

I'd be worried, however, about all the washers for depth. Not possible to
build in a bend to the tightening arm to bring it flush to the alternator?

It's possible but I'd need to disassemble part of the heat exchanger
to remove the adjusment arm, bend it and reinstall. What I've done
since the pictures were taken is to replace the washer stack with a
solid steel spacer. I've also replaced the original bolt with one
that is longer so that it now projects all the way through the
adjusment tab on the alternator, backed up by a grade 8 steel washer,
lock washer and nut. The whole assembly is extremely rigid with no
hint of vibration or flexing.

Reply:
I would watch the grade 8 for looseness. May be to high of grade bolt, may
need a grade 5. To keep a bolt tight, you need to stretch it a little. In
the elastic range and not the plastic range of the metal. Grade 8 bolts are
hard to get a good stretch on. I would at least go with a nyloc nut.

In article ,
says...
"Wayne.B" wrote in message
news
On Fri, 12 Nov 2010 11:21:39 -0500, "Flying Pig"
wrote:

Nice pix.

I'd be worried, however, about all the washers for depth. Not possible to
build in a bend to the tightening arm to bring it flush to the alternator?

It's possible but I'd need to disassemble part of the heat exchanger
to remove the adjusment arm, bend it and reinstall. What I've done
since the pictures were taken is to replace the washer stack with a
solid steel spacer. I've also replaced the original bolt with one
that is longer so that it now projects all the way through the
adjusment tab on the alternator, backed up by a grade 8 steel washer,
lock washer and nut. The whole assembly is extremely rigid with no
hint of vibration or flexing.

Reply:
I would watch the grade 8 for looseness. May be to high of grade bolt, may
need a grade 5. To keep a bolt tight, you need to stretch it a little. In
the elastic range and not the plastic range of the metal. Grade 8 bolts are
hard to get a good stretch on. I would at least go with a nyloc nut.


That's a good point. One reason for lock washers on high-grade bolts is
that they compress so you don't have to stretch the bolt.

Another reason for a lock washer is differences in thermal
expansion/contraction. If you tighten a steel bolt against an aluminum
flange when both are hot, the flange will contract at a different rate
than the bolt as it cools. The aluminum will contract at almost
twice the linear rate of the steel bolt. Conversely, tightening
the bolt when things are cool will increase the bolt tension when
both are hot as the aluminum expands more. This is probably
a good thing----especially as it lets you work without burning
your hands! ;-)

Balancing out all these factors is how mechanical engineers earn a
living. The rest of us use LocTite! (Note, LocTite may keep you
from losing the nut---it won't keep the belt tight in this application
if the thermal factors aren't accounted for.)

One thing that might help keep the belt tight is to use 60-grit
sandpaper across the adjustment arm on the side facing the aluminum
alternator flange. WHen you tighten down the bolt, the arm should
press some grooves into the aluminum to act as interlocking 'teeth'.

You should also be careful about overtorquing the bolt. Depending
on the thread size, you could strip out the threads in the aluminum
flange.


Most of these issues are things you learn over the years as
you maintain your boat. It sometimes helps to list the
issues just to make sure something isn't being overlooked.


Mark Borgerson

On Wed, 24 Nov 2010 07:20:17 -0800, Mark Borgerson
wrote:

That's a good point. One reason for lock washers on high-grade bolts is
that they compress so you don't have to stretch the bolt.

Another reason for a lock washer is differences in thermal
expansion/contraction. If you tighten a steel bolt against an aluminum
flange when both are hot, the flange will contract at a different rate
than the bolt as it cools. The aluminum will contract at almost
twice the linear rate of the steel bolt. Conversely, tightening
the bolt when things are cool will increase the bolt tension when
both are hot as the aluminum expands more. This is probably
a good thing----especially as it lets you work without burning
your hands! ;-)

Balancing out all these factors is how mechanical engineers earn a
living. The rest of us use LocTite! (Note, LocTite may keep you
from losing the nut---it won't keep the belt tight in this application
if the thermal factors aren't accounted for.)

One thing that might help keep the belt tight is to use 60-grit
sandpaper across the adjustment arm on the side facing the aluminum
alternator flange. WHen you tighten down the bolt, the arm should
press some grooves into the aluminum to act as interlocking 'teeth'.

You should also be careful about overtorquing the bolt. Depending
on the thread size, you could strip out the threads in the aluminum
flange.


Most of these issues are things you learn over the years as
you maintain your boat. It sometimes helps to list the
issues just to make sure something isn't being overlooked.

Lots of good points there and thanks for the comments.

For now everything is about as good as it's going to get for a while.
We'll be putting some serious hours on the boat in January so I'll be
keeping an eye on everything (and carrying a spare alternator or two).

With three heavy duty belts in place I'm hoping that belt wear and
slip will not be an issue. The old alternators were running fine on
two belts but they couldn't keep up with the electrical loads.

On Nov 24, 12:00*pm, Wayne.B wrote:
On Wed, 24 Nov 2010 07:20:17 -0800, Mark Borgerson





wrote:
That's a good point. *One reason for lock washers on high-grade bolts is
that they compress so you don't have to stretch the bolt.

Another reason for a lock washer is differences in thermal
expansion/contraction. * If you tighten a steel bolt against an aluminum
flange when both are hot, *the flange will contract at a different rate
than the bolt as it cools. * The aluminum will contract at almost
twice the linear rate of the steel bolt. *Conversely, tightening
the bolt when things are cool will increase the bolt tension when
both are hot as the aluminum expands more. * This is probably
a good thing----especially as it lets you work without burning
your hands! * ;-)

Balancing out all these factors is how mechanical engineers earn a
living. *The rest of us use LocTite! * (Note, LocTite may keep you
from losing the nut---it won't keep the belt tight in this application
if the thermal factors aren't accounted for.)

One thing that might help keep the belt tight is to use 60-grit
sandpaper across the adjustment arm on the side facing the aluminum
alternator flange. *WHen you tighten down the *bolt, the arm should
press some grooves into the aluminum to act as interlocking 'teeth'.

You should also be careful about overtorquing the bolt. *Depending
on the thread size, you could strip out the threads in the aluminum
flange.

Most of these issues are things you learn over the years as
you maintain your boat. *It sometimes helps to list the
issues just to make sure something isn't being overlooked.

Lots of good points there and thanks for the comments.

For now everything is about as good as it's going to get for a while.
We'll be putting some serious hours on the boat in January so I'll be
keeping an eye on everything (and carrying a spare alternator or two).

With three heavy duty belts in place I'm hoping that belt wear and
slip will not be an issue. *The old alternators were running fine on
two belts but they couldn't keep up with the electrical loads.- Hide quoted text -

- Show quoted text -

That will be a good test.

I am inclined to agree with some of the other posters about the amount
of electricity you seem to need. It would have been a lot simpler to
look for ways to reduce the power requirement rather than engineer a
solution to supply that much power. If you cook with propane then
what do you really need besides lights and power for the electronics?

On 11/30/10 8:49 AM, jamesgangnc wrote:
On Nov 24, 12:00 pm, wrote:
On Wed, 24 Nov 2010 07:20:17 -0800, Mark Borgerson





wrote:
That's a good point. One reason for lock washers on high-grade bolts is
that they compress so you don't have to stretch the bolt.

Another reason for a lock washer is differences in thermal
expansion/contraction. If you tighten a steel bolt against an aluminum
flange when both are hot, the flange will contract at a different rate
than the bolt as it cools. The aluminum will contract at almost
twice the linear rate of the steel bolt. Conversely, tightening
the bolt when things are cool will increase the bolt tension when
both are hot as the aluminum expands more. This is probably
a good thing----especially as it lets you work without burning
your hands! ;-)

Balancing out all these factors is how mechanical engineers earn a
living. The rest of us use LocTite! (Note, LocTite may keep you
from losing the nut---it won't keep the belt tight in this application
if the thermal factors aren't accounted for.)

One thing that might help keep the belt tight is to use 60-grit
sandpaper across the adjustment arm on the side facing the aluminum
alternator flange. WHen you tighten down the bolt, the arm should
press some grooves into the aluminum to act as interlocking 'teeth'.

You should also be careful about overtorquing the bolt. Depending
on the thread size, you could strip out the threads in the aluminum
flange.

Most of these issues are things you learn over the years as
you maintain your boat. It sometimes helps to list the
issues just to make sure something isn't being overlooked.

Lots of good points there and thanks for the comments.

For now everything is about as good as it's going to get for a while.
We'll be putting some serious hours on the boat in January so I'll be
keeping an eye on everything (and carrying a spare alternator or two).

With three heavy duty belts in place I'm hoping that belt wear and
slip will not be an issue. The old alternators were running fine on
two belts but they couldn't keep up with the electrical loads.- Hide quoted text -

- Show quoted text -

That will be a good test.

I am inclined to agree with some of the other posters about the amount
of electricity you seem to need. It would have been a lot simpler to
look for ways to reduce the power requirement rather than engineer a
solution to supply that much power. If you cook with propane then
what do you really need besides lights and power for the electronics?


Air conditioning, the jacuzzi, the double self-cleaning ovens, the
offshore pirate radio station...all require 'lectricity.

On Tue, 30 Nov 2010 05:49:55 -0800 (PST), jamesgangnc
wrote:

That will be a good test.

I am inclined to agree with some of the other posters about the amount
of electricity you seem to need. It would have been a lot simpler to
look for ways to reduce the power requirement rather than engineer a
solution to supply that much power. If you cook with propane then
what do you really need besides lights and power for the electronics?

It's really an all electric boat. It has large built-in fridges and
freezers, each with its own 110 volt compressor. Each one draws about
1 KW of power while running which is the primary demand while
underway, translating to about 100 amps at 12 volts. That power is
supplied from a 2 KW inverter when underway and we manage the load
manually by switching between the fridge and freezer every so often.
In addition to the compressors we average another 300 watts for
computers and other small electronics, so that's a steady requirement
for 100 to 130 amps at 12 volts just to supply the inverter. In
addition we have 12 volt house loads averaging about 30 amps for
things like radar, GPS units, multiple radios, auto pilot, etc. We
also have a house bank totaling about 1,000 amp-hours which supplies
the inverter at night. It needs to be recharged in the morning after
getting underway. That can easily consume another 100 amps during
the bulk stage of the recharge cycle.

In article ab125a9c-5fa3-4161-aac6-f0f346b15c92@
22g2000prx.googlegroups.com, says...
On Nov 24, 12:00*pm, Wayne.B wrote:
On Wed, 24 Nov 2010 07:20:17 -0800, Mark Borgerson





wrote:
That's a good point. *One reason for lock washers on high-grade bolts is
that they compress so you don't have to stretch the bolt.

Another reason for a lock washer is differences in thermal
expansion/contraction. * If you tighten a steel bolt against an aluminum
flange when both are hot, *the flange will contract at a different rate
than the bolt as it cools. * The aluminum will contract at almost
twice the linear rate of the steel bolt. *Conversely, tightening
the bolt when things are cool will increase the bolt tension when
both are hot as the aluminum expands more. * This is probably
a good thing----especially as it lets you work without burning
your hands! * ;-)

Balancing out all these factors is how mechanical engineers earn a
living. *The rest of us use LocTite! * (Note, LocTite may keep you
from losing the nut---it won't keep the belt tight in this application
if the thermal factors aren't accounted for.)

One thing that might help keep the belt tight is to use 60-grit
sandpaper across the adjustment arm on the side facing the aluminum
alternator flange. *WHen you tighten down the *bolt, the arm should
press some grooves into the aluminum to act as interlocking 'teeth'.

You should also be careful about overtorquing the bolt. *Depending
on the thread size, you could strip out the threads in the aluminum
flange.

Most of these issues are things you learn over the years as
you maintain your boat. *It sometimes helps to list the
issues just to make sure something isn't being overlooked.

Lots of good points there and thanks for the comments.

For now everything is about as good as it's going to get for a while.
We'll be putting some serious hours on the boat in January so I'll be
keeping an eye on everything (and carrying a spare alternator or two).

With three heavy duty belts in place I'm hoping that belt wear and
slip will not be an issue. *The old alternators were running fine on
two belts but they couldn't keep up with the electrical loads.- Hide quoted text -

- Show quoted text -

That will be a good test.

I am inclined to agree with some of the other posters about the amount
of electricity you seem to need. It would have been a lot simpler to
look for ways to reduce the power requirement rather than engineer a
solution to supply that much power. If you cook with propane then
what do you really need besides lights and power for the electronics?

Refrigeration? Air Conditioning?

Of these two, refrigeration is common even outside the tropics.

If you catch more fish than you can eat in a few days, it's handy
to be able to freeze a few day's worth. That can add significantly
to the refrigeration energy budget.

In the days when I cruised on chartered sailboats with just iceboxes,
we used to do a lot of pre-freezing and chilling to minimize ice
usage on a one-week cruise. We would pre-freeze things and keep
them frozen on the way to the charter. We once made the mistake
of putting some fruits and milk in the same cooler with some
frozen stuff over dry ice. Carbonated apples are interesting---
carbonated milk is less so.


Mark Borgerson