Sawing Versatility (continued)
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Pg. 1-3, Pg
4-6, Pg 7-9, Pg
10-12, Pg 13-15,
14-4. Adjust the upper blade guide so that it's
a maximum of 1/4" above the workpiece.
the height of the upper blade guide so that it's no more than
1/4" above the work (Figure
14-4). Then think through the cut before you turn on the
machine. Know where you'll put your hands as you feed the
stock into the blade; make sure the stock won't be blocked
by the bandsaw frame (Figure 14-5). When you're satisfied
that you can make the cut safely and without interference,
turn on the power, set the speed dial to the proper speed
and wait until the machine comes up to speed.
14-5. (A) Visualize the cut before you begin and
you can avoid the kind of throat interference that is
occurring here. (B) Started this way, the cut can be
made in one continuous pass.
comfortable stance in front and slightly to the left of the
blade, and start your cut. As you work, you may shift more
toward the center. Warning: Stand on the left side of the
blade. If the blade breaks it may fly to the right. Slowly
feed the stock into the blade. Use both hands to guide the
stock and keep it pressed firmly down against the table.
work, watch out for several problems that may cause the bandsaw
to bog down or produce an inaccurate cut:
the stock too fast
pressure (against the flat of the blade)
to turn a radius too small for the blade
or dull blades.
force the work, but you can feed fairly rapidly since the
machine cuts quickly. It's alright to pause in the cut for
a moment, but try not to remain stationary for too long. The
blade will heat up in the kerf, burning both the stock and
the blade. Feed the stock directly against the teeth, even
when cutting curves. To determine if the blade is the right
size for the curve, refer to Table 14-1.
blade continually wanders off the pattern, there are several
possible causes: The blade guides may be improperly adjusted.
Or you could be pressing against the side of the blade. You
may also be trying to cut a curve that's too tight for the
blade. If the blade wanders or "leads" just to one side or
the other, the teeth are improperly set. To correct the set
of the teeth, refer to the Bandsaw Owners Manual.
machine bogs down, stop a moment to let the bandsaw catch
up. Check to see if the blade is twisting in the guides. If
it is, you may be pressing against the side of the blade or
trying to turn a corner too tight for the blade. If the guides,
you're probably feeding the stock too fast. Once the bandsaw
is back up to running speed, feed the stock a little slower.
If the problem persists, check the blade to see if it's worn.
Replace dull or worn blades immediately.
blade jams on a scrap, turn off the machine and unplug the
power before you attempt to clear the scrap. If the blade
breaks, move around to the left side of the machine and turn
off the power. Wait until the wheels come to a complete stop
before removing the cover and the broken blade.
Getting a smooth, accurate cut begins by guiding the stock
carefully with both hands, feeding the stock forward against
the teeth at the proper rate, and not turning corners too
tight for the blade. Here are a few additional suggestions
to help you get the best results:
Outside the Pattern Line-For precision work, cut slightly
outside the line--in the waste stock--then sand to the final
dimension with a disc sander, belt sander, strip sander or
drum sander. Not only does this technique make it easier to
be accurate, the finished edge is smoother. The mill marks
left by the bandsaw are removed when you sand up to the line.
14-6. Break complicated cuts up into simple curves
Up a Cut-Break complicated cuts up into simple curves
and lines. Study your pat-tern to see how you might cut it
in several easy passes. Don't be afraid to cut into the waste
stock and loop around in order to reposition the blade at
a better angle to the pattern line (Figure
14-7. You may have to backtract with the blade in
order to cut some patterns. Plan ahead and avoid backing
out of cuts.
order to break up intricate patterns into simple cuts, you
may have to cut in to a point, then back the blade out and
cut from another angle (Figure
14-7). This is a safe technique if done carefully, but
there is always a danger that you may bind the blade, pull
it out of the guides and off the wheels. Sawdust can also
build up behind the blade, preventing you from backing it
out. To backtrack out of a cut longer than 1", turn off the
machine and let it come to a complete stop before backtracking.
If you can, avoid backtracking in long cuts altogether.
14-8. Round or square relief openings can facilitate
making internal cuts. When possible, plan the openings
as part of the design.
Relief Openings-A few well-placed relief openings will
give you sufficient turning room to make tight cuts. Square-cornered
relief openings can be formed with mortising bits and chisels;
round holes, made with drill bits, can be used when the blade
can't turn the radius required. Sometimes, corner holes are
used just to make bandsaw cutting easier; the radius of the
corner is exactly right because of the bit size that is used.
In all cases, be sure the layout for the corners, square or
round, is accurately done to conform to the design (Figure
14-9. Relief openings give you turning room to cut
tight internal corners. Click on image for larger view.
mind that making relief holes is one of the handiest techniques
for cutting intricate scrollwork (Figure
14-9). Drill these holes slightly inside the pattern line
in the waste stock.
Relief Cuts-Radial or tangential relief cuts make it possible
for you to cut a curve smaller than the blade can normally
turn. Make radial cuts toward the pattern line and backtrack
14-10). Then cut the desired curve. As the blade meets
up with each radial cut, a little piece of waste stock will
fall away. This, in turn, provides more room for the blade
14-10. To cut tight external curves, make several
radial cuts before you cut the pattern line.
14-11. You can aslo cut tight external curves by
making a series of tangential cuts as shown.
cuts by cutting on the pattern line until the blade starts
to bind slightly, then run off at a tangent to the curve.
Cut completely through the waste stock to the edge of the
workpiece, removing a small amount of stock. Start cutting
the pattern line again where you ran off at a tangent (Figure
14-11). Repeat this process until you've cut the desired
that radial cuts are useful when cutting both internal and
external curves. Tangential cuts can only be used on external
14-12. To cut corners and curves in tight spots,
feed the workpiece very lightly agains the blade and
let the teeth nibble away.
are times when you'll need to cut a detail in a pattern that's
too small to use any of the techniques described previously.
For these extra-fine jobs, feed the stock very, lightly against
the blade and let the teeth "nibble" it away (Figure
14-12). This is handy when you need to cut tiny corners
14-13. Wise planning of the layout can often make
it possible to join pieces to form a particular shape.
It is also a way to economize with material.
of the methods described in connection with scroll sawing
and jigsawing can be used to minimize layout and waste when
bandsawing. A specific application, which is typical, is the
forming of acurved rail (Figure
14-13). Two pieces that result from a single cut are joined
to form the arch shape.
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