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Default HD Panel Saw: How precise, and where is the source(s) of accumulated error(s)

When you walk up to the m/c and stop the needle pointer on the rule by
eye-balling it carefully, what is the accuracy resultant. I believe eye.
For this to be true the material, blade and rule zero positions have to be
set correctly. Lets say that it is set correctly. This is something you do
not have any control over anyways. The variable magnitude of this error if
set correctly is negligible. Cut to cut to cut. If it is not good the only
thing you could do is mentally add/move the needle approprriately after
taking a cut and comparing with a tape measure.. Lets say it is set and we
don't have to worry about it. In order to answer this I need answers from
people who know what it is like to stare down the pointer and graduations on
this machine The answers I hear, including none, may affect how I approach
the machine when I go get my material cut. Whether I get involved, and
whether I take a measurement after the first cuts V and H. I believe it is
entirely dependant on where you lay the pointer w/r/t the graduations on the
rule. I think it is easy to see the pointer on the 1/16" graduation lines.
It must be. Where is any introduced inaccuracy when you do this. It is easy
enough to divide this repetitively by aligning anywher in between these
lines, say divided by 25% increments, for example. so 1/64ths. I think you
can do this by visible inspection, no problem. But how would the machine
respond? But how repetable would it be? everytime. For here to there,
over, and back, over and over. Then there is the V cut stop block.

I love talking to any employee and determining if you'll have to reverse
engineer your project when some guy sets your cut once on the wrong line.
Hopefully if you're cutting an 8 foot long piece of ply four times
combined it's gonna be off by the thickness of the material. Remember we're
dealing with the thickness of the pointer, and the blade is already taken
care of. After a long discussion you ask, and he says no problem. So he
takes the first cut, lays out the tape measure and
exclaims PERFECT. Perfectly closer to the next closest line. Thats a buck.
Do you want the next sixty cuts?

a cut (sorry about errors):
I figured the panel saw out. For cutting horizontally there are two
platforms, and two reference rules. The rules don't move. One is to the
lower rest, the other to the upper rest, depending on the width of the sheet
and convenience. Absolute dimentions from bottom to top. No adding or
subtracting. No factoring in the blade. Because of gravity I draw all my
rips from bottom to top. The machine isn't set to measure the other way.
Maybe some employees would assume a perfect 48" and subtract if a drawing is
made that way. All dimensions should be contiguous, not combined, because
the top piece is removed after each cut. The thickness of the blade is zero
set. The rule never moves. 1/8" is set when the machine is built. That
is, with the needle pointer at 15-15/16", thats what you get. If you were
resting on the lower platform, say 30" away, use the other rule. It is
offset by 30" It would read 15-15/16", The machine cuts straight as an
arrow and perfectly normal.
With vertical cuts, the blade is slid over to a lock position and rides up
and down. The wood is slid side to side to a stop block. Accuracy of
consecutive cuts just depends on moving the wood over to lightly touch the
stop block. The rule for the stop block starts at zero and works both ways.
The blade is accounted for, the rules origins start .250" appart (two 1/8"
saw kerfs). The stop block is a steel fixture with a cam clamp that rides
on a rail. It is a bit figetty, but done firmly and right its all over.
The V and H rules are the same. and the indicating pointers are the same.
There is no paralax error to worry about. Pointer to rule is a fractions of
a millimeter. White steel rule with black graduations. Black spring steel
pointers. There is no operational errror introduced.

These are posible sources of error: (assume sharp blade, and sraight factory
material edge)
the rules themselves are not accurate or consistent throughout the full
length of blade travel (w/r/t standard at Bureau of measurements)
the rule zero position is not set correctly w/r/t material zero, or the
blade zero position
the material, blade, pointer or rule zero position is not constrained
blade or m/c runout during operation
paralax error or other visible or mechanical error in setup of indicator
pointer at position on rule
V cuts: the position, alignment and constraint of the stop block

I always remember that 1/32" is approximately 1/33". 32s or 33s, who cares.
And I know 1/33
divided by 1/33 is .99999... (1.0000...). So a 1/32" (1/33")=~ .033..." In
words, a thirty-second is thirty-three thou.



 
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