Cast iron trunnions on a band saw?
 

Grizzly has up graded their 17 and 19" extreme band saws by changing the
trunnions to cast iron, and raising the price $200. Are cast iron trunnions
really worth $200 (or 25%) more? The old saws actually weight a couple
pounds more.

Cast iron trunnions on a band saw?
 

"Toller" wrote in message
...
Grizzly has up graded their 17 and 19" extreme band saws by changing the
trunnions to cast iron, and raising the price $200. Are cast iron
trunnions really worth $200 (or 25%) more? The old saws actually weight a
couple pounds more.

Or course not, but there may have been other improvements, plus the cost of
raw material is skyrocketing so it was, perhaps, a good time to give an
overall increase.

Cast iron trunnions on a band saw?
 

Toller wrote:
Grizzly has up graded their 17 and 19" extreme band saws by changing the
trunnions to cast iron, and raising the price $200. Are cast iron trunnions
really worth $200 (or 25%) more? The old saws actually weight a couple
pounds more.

Depends...

If the previous designs have been found to be too light and flexible,
surely.

As Edwin points out, metal costs have increased dramatically over last
several years as well as transportation costs (it costs Griz to get
stuff here before the transportation to you) and so on.

It is also true there's far more to "value" than simply material costs.

--

Cast iron trunnions on a band saw?
 

"dpb" wrote in message ...
Toller wrote:
Grizzly has up graded their 17 and 19" extreme band saws by changing the
trunnions to cast iron, and raising the price $200. Are cast iron
trunnions really worth $200 (or 25%) more? The old saws actually weight
a couple pounds more.

Depends...

If the previous designs have been found to be too light and flexible,
surely.


Then there is the consideration that cast iron, as opposed to aluminum,
doesn't make a good abrasive like AlOx, preserving the contour and
clearance, thereby accuracy, for a longer time. Stamped metal isn't in the
same league, of course.

Cast iron trunnions on a band saw?
 

On Jul 22, 11:00 am, "George" wrote:
"dpb" wrote in ...
Toller wrote:
Grizzly has up graded their 17 and 19" extreme band saws by changing the
trunnions to cast iron, and raising the price $200. Are cast iron
trunnions really worth $200 (or 25%) more? The old saws actually weight
a couple pounds more.

Depends...

If the previous designs have been found to be too light and flexible,
surely.

Then there is the consideration that cast iron, as opposed to aluminum,
doesn't make a good abrasive like AlOx, preserving the contour and
clearance, thereby accuracy, for a longer time. Stamped metal isn't in the
same league, of course.

Cast iron is harder. It machines better. It's rich in graphite,
which helps moving parts move smoothly instead of sticking
and galling.

Cast iron trunnions on a band saw?
 

Father Haskell wrote:
Cast iron is harder. It machines better. It's rich in graphite,
which helps moving parts move smoothly instead of sticking
and galling.


I recall hearing that another advantage is the extra weight/density of
cast iron, which gives the wheels more inertia, like flywheels.

Cast iron trunnions on a band saw?
 

On Jul 22, 1:47 pm, Gordon Airporte wrote:
Father Haskell wrote:
Cast iron is harder. It machines better. It's rich in graphite,
which helps moving parts move smoothly instead of sticking
and galling.

I recall hearing that another advantage is the extra weight/density of
cast iron, which gives the wheels more inertia, like flywheels.

Which dampens vibrations and helps machinery last longer.
Not sure why trunnions would need more inertia, though.

Cast iron trunnions on a band saw?
 

On Sun, 22 Jul 2007 11:09:49 -0700, Father Haskell wrote:


I recall hearing that another advantage is the extra weight/density of
cast iron, which gives the wheels more inertia, like flywheels.

Which dampens vibrations and helps machinery last longer. Not sure why
trunnions would need more inertia, though.

Possibly he meant momentum. Extra momentum in a rotating piece of cast
iron would minimise 'slowdown' in the blade when entering a workpiece
that's higher in moisture or denser or harder (like hitting a knot).

Just a guess. A WAG at that :-).

--
Registered Linux User 413057.
Both Mandriva 2007.1 and Ubuntu 7.04
You can have it all. My empire of hurt.

Liverpool F.C.-more European Cups than all
the other English teams put together :-)

Cast iron trunnions on a band saw?
 

Aardvark wrote:
On Sun, 22 Jul 2007 11:09:49 -0700, Father Haskell wrote:


I recall hearing that another advantage is the extra weight/density of
cast iron, which gives the wheels more inertia, like flywheels.
Which dampens vibrations and helps machinery last longer. Not sure why
trunnions would need more inertia, though.

Possibly he meant momentum. Extra momentum in a rotating piece of cast
iron would minimise 'slowdown' in the blade when entering a workpiece
that's higher in moisture or denser or harder (like hitting a knot).

"Trunnions" don't rotate, however...

"Mass" would be the most likely relevant property related for them as
well as simply more strength/rigidity if as previous hypothesized the
former tended to be undersized so they flexed under load or warped when
locking in place...

--

Cast iron trunnions on a band saw?
 

On Mon, 23 Jul 2007 16:56:18 GMT, Aardvark
wrote:

On Sun, 22 Jul 2007 11:09:49 -0700, Father Haskell wrote:


I recall hearing that another advantage is the extra weight/density of
cast iron, which gives the wheels more inertia, like flywheels.

Which dampens vibrations and helps machinery last longer. Not sure why
trunnions would need more inertia, though.

Possibly he meant momentum. Extra momentum in a rotating piece of cast
iron would minimise 'slowdown' in the blade when entering a workpiece
that's higher in moisture or denser or harder (like hitting a knot).

Just a guess. A WAG at that :-).

He just confused the trunnion with the wheels. The trunnion is the
cradle the table sits on that allows it to be angled. The only
significant advantage would be if it keeps the table locked more
securely. I dunno what the grizzly's are like, but once I lock the
table on my delta if I try to move it the whole saw moves not the
table. But that's also true of my little pos ryobi 9" bandsaw and I
assure you there is no cast iron to be found anywhere on it.

On my new grizzly 8" disc / 1" belt sander the table and trunnion for
the disc table are both cast iron, however they didn't machine the
mating surfaces, just rough painted castings that don't particularly
fit well together. I mention this not to imply anything about
grizzly's band saws, but just that sometimes they like to be able to
throw around "cast iron!" this and that to look better on paper
without actually being any better. I had to toss the trunnion in the
trash and make my own fixed support to make it usable.



-Leuf

Cast iron trunnions on a band saw?
 

On Jul 23, 3:20 pm, Leuf wrote:
On Mon, 23 Jul 2007 16:56:18 GMT, Aardvark
wrote:

On Sun, 22 Jul 2007 11:09:49 -0700, Father Haskell wrote:

I recall hearing that another advantage is the extra weight/density of
cast iron, which gives the wheels more inertia, like flywheels.

Which dampens vibrations and helps machinery last longer. Not sure why
trunnions would need more inertia, though.

Possibly he meant momentum. Extra momentum in a rotating piece of cast
iron would minimise 'slowdown' in the blade when entering a workpiece
that's higher in moisture or denser or harder (like hitting a knot).

Just a guess. A WAG at that :-).

He just confused the trunnion with the wheels. The trunnion is the
cradle the table sits on that allows it to be angled. The only
significant advantage would be if it keeps the table locked more
securely. I dunno what the grizzly's are like, but once I lock the
table on my delta if I try to move it the whole saw moves not the
table. But that's also true of my little pos ryobi 9" bandsaw and I
assure you there is no cast iron to be found anywhere on it.

On my new grizzly 8" disc / 1" belt sander the table and trunnion for
the disc table are both cast iron, however they didn't machine the
mating surfaces, just rough painted castings that don't particularly
fit well together. I mention this not to imply anything about
grizzly's band saws, but just that sometimes they like to be able to
throw around "cast iron!" this and that to look better on paper
without actually being any better. I had to toss the trunnion in the
trash and make my own fixed support to make it usable.

That's typical Chaiwanese craftsmanship -- cut back heavily on
finishing, finish only where it counts. I see they've lowered their
standards. It's time you learned the fine art of scraping cast iron.

Cast iron trunnions on a band saw?
 

Leuf wrote:

He just confused the trunnion with the wheels.

He did. Oops.

Cast iron trunnions on a band saw?
 

On Mon, 23 Jul 2007 22:38:56 -0400, Gordon Airporte wrote:

Leuf wrote:

He just confused the trunnion with the wheels.

He did. Oops.

LOL. An earlier post in the thread mentioned cast iron wheels and it
seems I promptly forgot what we were talking about. First signs of aging
I suppose :-)

--
Registered Linux User 413057.
Both Mandriva 2007.1 and Ubuntu 7.04
You can have it all. My empire of hurt.

Liverpool F.C.-more European Cups than all
the other English teams put together :-)

Cast iron trunnions on a band saw?
 

"Aardvark" wrote in message
...
LOL. An earlier post in the thread mentioned cast iron wheels and it
seems I promptly forgot what we were talking about. First signs of aging
I suppose :-)


You're not there yet if you don't recognize that the mind is the SECOND
thing to go....