I recently bought one of the Rockler phenolic resin zero clearance
inserts.
(http://www.rockler.com/product.cfm?p...ro%20clearance)

I cut the slot by raising my sawblade through the insert as per the
instructions (and in fact moved it all the wa up and down a couple of times to
make sure it was cut cleanly)

However, now whenever I run the saw, there is a high pitched sound
coming from the blade "rubbing" against the sides of the insert
whenever the blade is at any height above the insert.

In addition to being annoying, I am concerned that this friction will
suck power from my saw.

-- So, is such noise (and associated rubbing) normal?
-- If not, what can I do about it?

(I was thinking about widening the slot on one side by adding a piece
of paper as a spacer to one of the washers but am not sure how to do
widen the other side. Also, not sure whether this would defeat the
purpose of a "zero clearance" insert)

Note my saw is pretty well adjusted with runout of just .001"
(actually, I imagine that the reason I am having this problem is that
the runout is so little since with a larger runout or wobble, the slit
would have been cut wider)

Thanks!

On Jun 8, 12:48*am, blueman wrote:
I recently bought one of the Rockler phenolic resin zero clearance
inserts.
(http://www.rockler.com/product.cfm?p...ro%20clearance)

I cut the slot by raising my sawblade through the insert as per the
instructions (and in fact moved it all the wa up and down a couple of times to
make sure it was cut cleanly)

However, now whenever I run the saw, there is a high pitched sound
coming from the blade "rubbing" against the sides of the insert
whenever the blade is at any height above the insert.

In addition to being annoying, I am concerned that this friction will
suck power from my saw.

-- So, is such noise (and associated rubbing) normal?
-- If not, what can I do about it?

(I was thinking about widening the slot on one side by adding a piece
of paper as a spacer to one of the washers but am not sure how to do
widen the other side. Also, not sure whether this would defeat the
purpose of a "zero clearance" insert)

Note my saw is pretty well adjusted with runout of just .001"
(actually, I imagine that the reason I am having this problem is that
the runout is so little since with a larger runout or wobble, the slit
would have been cut wider)

Thanks!

The friction should be minimal and not enough to worry about. The
noise is the same cavitation that sirens are based on. It small air-
pockets (between the teeth) getting chopped up.
Sometimes a squirt of TopKote quiets scuffing sounds down a bit.
I am making the assumption that when you raised the blade for cut#1,
it was adjusted to dead-nuts verticality.
Bringing the blade up on even the slightest angle will give you grief.

As you use it, it will widen up all by itself.

r

On Sun, 08 Jun 2008 04:48:41 GMT, blueman wrote:

...
However, now whenever I run the saw, there is a high pitched sound
coming from the blade ...In addition to being annoying, I am concerned that this friction will
suck power from my saw.

Althought the sound might be annoying, I seriously doubt that you'll
notice any power loss. After all, a "Zero Clearance" insert should
have "zero clearance".

-- So, is such noise (and associated rubbing) normal?

I always make my own ZCIs so I've never used the specific ZCI you
reference. What you report is the same thing I've noted when I put a
new ZCI in service. My experience is that it diminishes and eventually
disappears as the slot wears with use. How much cutting have you done
with the ZCI in place.

-- If not, what can I do about it?

Personally, I wouldn't worry about it.

Tom Veatch
Wichita, KS
USA

"blueman" wrote in message
However, now whenever I run the saw, there is a high pitched sound
coming from the blade "rubbing" against the sides of the insert
whenever the blade is at any height above the insert.

In addition to being annoying, I am concerned that this friction will
suck power from my saw.

-- So, is such noise (and associated rubbing) normal?
-- If not, what can I do about it?

(I was thinking about widening the slot on one side by adding a piece
of paper as a spacer to one of the washers but am not sure how to do
widen the other side. Also, not sure whether this would defeat the
purpose of a "zero clearance" insert)

It will go away in time. Zero clearance means just that and a rub is common.
Eventually it will wear and not rub. If you are concerned about it zapping
power, you need a better saw anyway.

blueman wrote:


However, now whenever I run the saw, there is a high pitched sound
coming from the blade "rubbing" against the sides of the insert
whenever the blade is at any height above the insert.


I wouldn't worry about it. The noise may be caused by the air coming
off the teeth of the blade "whistling" as they pass through the insert.
In any event the slot will widen a bit due to slight deflections in
the blade as it is used.

--
Jack Novak
Buffalo, NY - USA

Tom Veatch writes:

On Sun, 08 Jun 2008 04:48:41 GMT, blueman wrote:

...
However, now whenever I run the saw, there is a high pitched sound
coming from the blade ...In addition to being annoying, I am concerned that this friction will
suck power from my saw.

Althought the sound might be annoying, I seriously doubt that you'll
notice any power loss. After all, a "Zero Clearance" insert should
have "zero clearance".

-- So, is such noise (and associated rubbing) normal?

I always make my own ZCIs so I've never used the specific ZCI you
reference. What you report is the same thing I've noted when I put a
new ZCI in service. My experience is that it diminishes and eventually
disappears as the slot wears with use. How much cutting have you done
with the ZCI in place.

Haven't done much cutting yet -- but since my saw has bogged down
before on ripping 8/4 hardwood, I was concerned about losing power -
but it seems like that is not a real worry

-- If not, what can I do about it?

Personally, I wouldn't worry about it.

Thanks!

On Jun 7, 11:48 pm, blueman wrote:
I recently bought one of the Rockler phenolic resin zero clearance
inserts.
(http://www.rockler.com/product.cfm?p...ro%20clearance)

I cut the slot by raising my sawblade through the insert as per the
instructions (and in fact moved it all the wa up and down a couple of times to
make sure it was cut cleanly)

However, now whenever I run the saw, there is a high pitched sound
coming from the blade "rubbing" against the sides of the insert
whenever the blade is at any height above the insert.

In addition to being annoying, I am concerned that this friction will
suck power from my saw.

-- So, is such noise (and associated rubbing) normal?
-- If not, what can I do about it?

(I was thinking about widening the slot on one side by adding a piece
of paper as a spacer to one of the washers but am not sure how to do
widen the other side. Also, not sure whether this would defeat the
purpose of a "zero clearance" insert)

Note my saw is pretty well adjusted with runout of just .001"
(actually, I imagine that the reason I am having this problem is that
the runout is so little since with a larger runout or wobble, the slit
would have been cut wider)

Thanks!

I haven't used that one but I've had a couple ZC inserts and did find
that the howl was different for each - and often it was different with
each blade I used. I also wouldn't be surprised if the phenolic was
amplifying it by vibrating. You might want to try and dampen it
somehow just to see if it made a difference but I don't know what I'd
use or where I'd put it.

And as others have said, it will change as it wears.

I recently bought one of the Rockler phenolic resin zero clearance
inserts.
(http://www.rockler.com/product.cfm?p...ro%20clearance)

I cut the slot by raising my sawblade through the insert as per the
instructions (and in fact moved it all the wa up and down a couple of
times to
make sure it was cut cleanly)

However, now whenever I run the saw, there is a high pitched sound
coming from the blade "rubbing" against the sides of the insert
whenever the blade is at any height above the insert.

In addition to being annoying, I am concerned that this friction will
suck power from my saw.

-- So, is such noise (and associated rubbing) normal?
-- If not, what can I do about it?

(I was thinking about widening the slot on one side by adding a piece
of paper as a spacer to one of the washers but am not sure how to do
widen the other side. Also, not sure whether this would defeat the
purpose of a "zero clearance" insert)

Note my saw is pretty well adjusted with runout of just .001"
(actually, I imagine that the reason I am having this problem is that
the runout is so little since with a larger runout or wobble, the slit
would have been cut wider)

Thanks!

I suspect, as others have, that it's the cavitation of the teeth of the
blade cutting the "stationary" air at the edge of the blade opening...it'll
wear in so there is a little more clearance...that should take care of the
high pitched howl...if you really need to quiet it done, you can speed the
process by sanding the opening a little with a little sandpaper...JUST A
LITTLE!!!

As to losing power to the close fit on the insert, if you're THAT close to
the edge of your power, get a more powerful saw.

Mike