Our 4x6 Harbor Freight horizontal bandsaw isn't cutting straight. The
blade consistently wanders toward the vise when cutting on the
downstroke, so that when a cut of 2" stock is complete there 1/16"
clearance between the blade and stock at the bottom of the cut, but no
clearance at the top of the cut.
I've tightened the blade and adjusted the clearance between each set
of guide bearing so the blade can't move or twist side-to-side, all to
no avail. I'm using a Starrett bi-metal blade.
Has anyone else experienced this problem? I assume what's causing
this is that the blade isn't exactly perpendicular to the table,
making it follow a slightly "off" path. But I can't see any way to
adjust this. Am I missing something? TIA.
-Jim
Has it always cut in that fashion, or did it start doing so recently? If
it's something new, it's highly likely that the set is buggered on one side
of the blade, forcing the blade to the opposite side. That's a common
occurrence with band saws. In spite of the fact that bi-metal blades are
far superior to carbon steel blades, I've always chosen to use the far less
expensive carbon steel blades because I've had more failures due to damaged
blades than I have ever had from wearing them out. That was true even when
I used my saw in my now defunct small commercial shop.
As far as I know, if it's not the blade, the only way to correct the problem
is to have adjustable guides that swivel the blade to correct its path. I
bought a Wells A7 saw in the late 60's that had that feature. Later models
of the same saw were still adjustable, but not with the turn of a screw.
Much harder to make the adjustment reliably with the newer, but cheaper to
produce, setup.
Harold
In my experience its usually a worn blade that causes my 4 x 6 bandsaw to
wander out of square on the cuts. Try a new blade and see if the problem
goes away.
Good luck-
Paul T.
Bandsaws will wander, some more than others. The blade is not rigid. It
will follow the path of least resistance. You can minimize the amount of
wander by proper setup. But you can never count on a perfect cut.
I was taught to allow .060" extra length per inch of thickness so there is
enough material on the cut end to finish to correct dimensions. Your
results appear to be within this tolerance.
I bought one of these saws, a JET one, 23 years ago. They are all the
same though. Mine did the same as yours. I took it back and was told
it was the blade. Well, the blade was ruined because the saw wasn't
cutting correctly. With the blade set 90 degrees to the base, as it
should be, the blade would move in as the saw went down. So, the
problem on mine was the pivot pin holes were not bored parallel to the
saw base. You can check yours for this problem. Clamp a square to the
saw base. With the saw all the way down measure from the blade to the
square. Then raise the saw two inches and check again. This will show
if the pivot is wrong. You should get about the same error as the cuts
are turning out.
ERS
Have you checked the 4x6 bandsaw FAQ? There are a number of tips on there.
That FAQ came almost entirely from the accumulated wisdom of this NG along
with some distilled from HSM, PIM, ME or MEW articles.
::
:>Our 4x6 Harbor Freight horizontal bandsaw isn't cutting straight. The
:>blade consistently wanders toward the vise when cutting on the
:>downstroke, so that when a cut of 2" stock is complete there 1/16"
:>clearance between the blade and stock at the bottom of the cut, but no
:>clearance at the top of the cut.
:>
:>I've tightened the blade and adjusted the clearance between each set
:>of guide bearing so the blade can't move or twist side-to-side, all to
:>no avail. I'm using a Starrett bi-metal blade.
:>
:>Has anyone else experienced this problem? I assume what's causing
:>this is that the blade isn't exactly perpendicular to the table,
:>making it follow a slightly "off" path. But I can't see any way to
:>adjust this. Am I missing something? TIA.
:>
:>-Jim
:I bought one of these saws, a JET one, 23 years ago. They are all the
:same though. Mine did the same as yours. I took it back and was told
:it was the blade. Well, the blade was ruined because the saw wasn't
:cutting correctly. With the blade set 90 degrees to the base, as it
:should be, the blade would move in as the saw went down. So, the
:problem on mine was the pivot pin holes were not bored parallel to the
:saw base. You can check yours for this problem. Clamp a square to the
:saw base. With the saw all the way down measure from the blade to the
:square. Then raise the saw two inches and check again. This will show
:if the pivot is wrong. You should get about the same error as the cuts
:are turning out.
I had that same problem with my Harbor Freight model. I had to bore out
the pivot hole on one side of the base and insert a sleeve to bring the
properly aligned, but oversized, hole down to size. That saw base
looked pretty ridiculous clamped to the table of my little Clausing 8520
mill.
If it isn't the blade set worn off on one side, a common occurrence,
you can easily check to see if the blade is moving square to the base.
Just set a square on the base and move the upright portion close to
the blade and move the head from up to down position. Eyeball the gap
to see if the blade moves parallel to the square. If it does, it's
probably the blade or the guide setup, if not, you've got either a
tweaked base or the head pivot is screwed up somehow. I've had the
pivot shaft slide out on me and I've not caught it, made for some
interesting times. Is this a new saw or did it just start doing it?
You might also check your blade, I've had a few where the weld was
skewed and the blade didn't lay flat on a flat surface. Check the new
one before you put it on. I've never had that problem with Lenox
blades.
Stan
Thanks for everyone's advice. FWIW, I ended up solving this problem
by simply inserting a shim under one side of the leading guide bearing
bracket on the swinging frame. This twisted the blade to make it
perpendicular to the table, creating a straighter cut. Just thought
I'd mention it since I hadn't seen it suggested elsewhere.
-Jim
:> Our 4x6 Harbor Freight horizontal bandsaw isn't cutting straight. The
:> blade consistently wanders toward the vise when cutting on the
:> downstroke, so that when a cut of 2" stock is complete there 1/16"
:> clearance between the blade and stock at the bottom of the cut, but no
:> clearance at the top of the cut.
:>
:> I've tightened the blade and adjusted the clearance between each set
:> of guide bearing so the blade can't move or twist side-to-side, all to
:> no avail. I'm using a Starrett bi-metal blade.
:>
:> Has anyone else experienced this problem? I assume what's causing
:> this is that the blade isn't exactly perpendicular to the table,
:> making it follow a slightly "off" path. But I can't see any way to
:> adjust this. Am I missing something? TIA.
:>
:> -Jim
:
:Thanks for everyone's advice. FWIW, I ended up solving this problem
:by simply inserting a shim under one side of the leading guide bearing
:bracket on the swinging frame. This twisted the blade to make it
:perpendicular to the table, creating a straighter cut. Just thought
:I'd mention it since I hadn't seen it suggested elsewhere.
That solves a different problem than the one I had. Yes, the blade
needs to be perpendicular to the table, and if the blade guides can't be
adjusted to make it perpendicular then you have to work out some other
fix. But, the movement of the blade as the frame swings down also has
to be perpendicular to the table. That's a completely independent
problem, and you can't fix it by fiddling with the blade guides. The
test is to set a square on the table and see if the blade will just
graze one edge of the vertical arm of the square as you swing the frame
down. If that's wrong, the only fix is to correct the mis-bored pivot
holes in the base.
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