alignment or technique ...
Wyman Eric Miles
The Forrest WWII arrived from Toolcrib today. While I'm by nature skeptical of
any product's reputation until I've experienced it myself, I had high hopes.
After installing the blade, re-checking the overall alignment of things, and
making a few test cuts in white oak and hickory, it's impressive.
Sort of.
It's not the kind of wet-your-pants impressive I'd hoped for.
It's better than the Freud it replaced. Crosscuts are perfect. Rips leave
something to be desired. Which brings me to my question:
What I'm seeing are saw marks, admittedly moderate ones, on the lower half of the
ripped edge, all along its length. The arcs show cuts made by both the rising
(rear path) and descending (front path) teeth. The upper half of the ripped face
is perfectly smooth.
Additionally, and this is a problem that's plagued every blade I've used and
seems to resist all attempts to eliminate it via careful alignment or changes in
technique, is that the corner of the ripped edge, closest to the table, gets
nicked slightly as the piece passes completely by the blade. What the heck
causes this?
I've checked that the blade is perpendicular to the table, that it's parallel to
the mitre gauge slots, my arbor runout, table flatness, throat plate level, rip
fence is parallel to the blade, with 1/64" toe out. For the life of me, I can
explain either the saw marks or that tendency to eat a little more of the passing
corner.
Any ideas?
--
Wyman Miles
Manager of Infrastructure, Rice University, Texas.
(713) 348-5827, e-mail:wym...@rice.edu, pager:wym...@pager.rice.edu
Steve Strickland
wrote:
Wyman, I have some suggestions.
First, I align the fence to be perfectly parallel with the miter slot and
then align the blade with the miter slot as well. I use a dial micrometer
and get the error under 0.001". Any misalignment causes the marking like
you are seeing. A 64th alignment error is pretty large.
Next, I square my blade to the table top with a machinists stainless steel
square. Carpentry squares are nowhere near square enough.
The rough edge on the underside and trailing end of the board is called
tearout. This is eliminated by adding a sacrificial piece of wood along
the edge where the blade passes through. It doesn't have to be very thick,
a 16th inch would do. It works just like a zero clearance insert.
Sometimes plain masking tape will work.
You can get more improvement in quality and performance from a critical
alignmnet than you can by spending money on blades. There are several good
articles on the procedure. The key thing is to use high quality measuring
tools during alignment.
--
Steve Strickland, Puzzlecraft
st...@puzzlecraft.com
www.puzzlecraft.com
Leon
If you are getting that ping noise and the little nick at the end of the
board, you are not ripping parallel to the blade.
That said, you mentioned that your rip fence is parallel to your blade with
1/64 toe out...???
Your fence should be in the .001"-.003" range to get decent cuts.
Apparently you are in the .015" range now. Dead even parallel with NO toe
in or out is what you want to shoot for. As long as your wood approaches
the blade at an angle you are going to get tooth marks on your wood. Get a
dial indicator that measures in the thousands and adjust your miter slot to
be parallel to your blade and then adjust your fence to be parallel to that
same miter slot. You really want to shoot for .001-.003" between the back
and front of your blade to the miter slot. Measure using the same tooth on
the blade with it raised all they way up.
charlieb
has a joined edge and if that edge is against the
fence.
--
char...@accesscom.com
woodworking site
www.wood-workers.com/users/charlieb
Brett A. Thomas
BTW, I know where he got this from - _The Table Saw_ book is of the
opinion that the back of your fence should be 1/64th away from your
blade to prevent binding and kicback: "I like to set my rip fence so
that it is slightly farther (about 1/64 in.) from the back of the
blade than from the front, so the rear teeth just miss the stock being
cut. This setting gives a smoother cut and reduces the potential for
kickback." From page 56.
So, it's not just that this poor fellow is on crack.
Leon
away from the back of the saw. And yes while this will reduce the chance of
kick back assuming your board edge against the fence is perfectly straight,
However it does lend itself to leaving marks on one of the pieces of wood.
In this case the waste piece will be the likely target. Not pushing the
wood parallel to the blade will result is tooth marks on one of the pieces
of wood. Proper technique and properly jointed wood will reduce the chance
of kick back.
I did not mean to sound as though his idea of having 1/64" more clearance at
the back of the blade was unfounded. I was just trying to explain that this
was most likely the source of his problem.
Leon
he has owned. Certainly at one time or another he has used straight stock.
Good point concerning the stock being against the fence. With the fence
being that far out of parallel from the blade, a longer board will
eventually want to pull away from the fence. The board simply is not going
to track properly.
"charlieb" <char...@accesscom.com> wrote in message
news:3C8F17...@accesscom.com...
Lawrence Wasserman
OK, if it is from front to back of the BLADE it is way too much. If
everything else is adjusted as you say check the fence surface itself
with a good straightedge and make sure it is flat. Another thing I
don't believe you mentioned is the splitter, make sure it is aligned
and parallel with the blade.
--
Larry Wasserman Baltimore, Maryland
lwas...@charm.net
charlieb
Having a knife that's the same width as the saw blade,
or a smidge wider with a knife edge on the blade side,
keeps the kerf open and away from the saw's teeth.
Most Euro saws have a curved splitter/ riving knife
right behind the blade. The edge closest to the blade
is curved to follow the curve of the saw blade so it
can be set very close behind the blade. It raps around
almost the top rear quarter of the saw blade. Just one
more things to help reduce kick back or worse yet -
board tossing.
Wayne Cannon
were as "smooth as glass", both rip and crosscut. I feel the blade is all that
it's advertised to be (and maybe more), and would suspect tuning might help.
I'm not a stickler for tuning, but followed basic tuneup procedures for my
stock Jet cabinet saw (I haven't done anything to true the arbor flange or add
link belts, etc.; just blade and fence parallel with miter slot). I do use a
Forrest blade "stabilizer" on one side. I set the fence parallel with the
slots, with no intentional toe-out (I haven't had a need).
How do you quantify "smooth as glass" -- no visible saw marks; none. Using the
same technique as this month's FWW saw blade review, the white oak rip cuts I
made 6 months ago are smooth within .002 min-to-max, compared with FWW results
of .0016 with their best blade (the WWII). The extremes coincided with the
grain, so the difference betweem summer (when they were cut) and winter is
probably a factor. The FWW handplane cut was smooth within .0014 to .0017.
I just checked my saw. The fence is toed-out (the back is further away from
the blade than the front) by .005 over its 30-inch length (1/64-inch is .0156).
The blade is toed-out (the back is further from the fence than the front) by
.0015. There is .001 of total run-out (arbor plus blade) near the edge of the
blade as it's rotated (Jim Tolpin recommends <.012).
--Wayne
Wyman Eric Miles wrote:
--
(Change "nospam" to "wcannon" for e-mail)
Wayne Cannon
--Wayne
charlieb wrote:
> Forgot to ask if he's using a splitter / riving knife.
> Having a knife that's the same width as the saw blade,
> or a smidge wider with a knife edge on the blade side,
> keeps the kerf open and away from the saw's teeth.
>
> Most Euro saws have a curved splitter/ riving knife
> right behind the blade. The edge closest to the blade
> is curved to follow the curve of the saw blade so it
> can be set very close behind the blade. It raps around
> almost the top rear quarter of the saw blade. Just one
> more things to help reduce kick back or worse yet -
> board tossing.
>
>
--
Stephen Pawlowskis
similar problem with my old CS where I always had saw marks on one side of
the cut no matter what I did. I attributed them to the fact that the saw
arbor had side play in it. In other words you could slide the arbor in and
out of the bearings a small amount. I believe that this allowed the saw to
"ride" on one side of the cut, kinda spring loaded against it, rather than
staying centered in the kerf. I may be wrong, as I never bothered to fix
this problem and have since gotten a new saw but you may want to check your
arbor for side-to-side play if you haven't already.
Wyman Eric Miles <wym...@rice.edu> wrote in message
news:a6mk2i$mo9$1...@joe.rice.edu...
Eric Lund
This type of splitter is one of the few good things I can say about my
Shopsmith saw. I can honestly say I've never had a kickback on it. I must
admit, it cuts pretty well with a Forrest WWII. Still, it lacks power, so I
can't always push wood through fast enough to avoid all burning. Ripping
hard maple and even white oak is a real challenge.
Roger Haar
Just some thoughts:
1. In ripping you may be relieving some tension
that can drive the wood in odd fashions. But this
would come and go along the rip cut.
2. Most fences that I have looked at seem to have
a some flex to them. That is if you push the
stock too hard against the fence, the fence will
be pushed away from the blade. The movement I
have seem is much more than a few thousands, and
often more than a 1/64. Thus you might be pushing
the stock to hard against the fence.
Thanks
Roger