Friday, December 30, 2005

Shop-made Bandsaw Table and Fence

under contruction -- updated 01-19-06


This website illustrates how I constructed a combination enlarged table/adjustable fence/sled for my laguna tools 18 inch bandsaw.

(Let me express my appreciation for the assistance given by James Haddock in the early stage of developing this project. Let me add, too, that I take a little pride in reporting that my shop-made bandsaw table and fence came in 17th, from among 550 entries, in the "Solving a Woodworking Problem" contest, conducted by Woodworker's Supply, Summer and Fall, 2005.)


I have owned my bandsaw for 4 years, since June 2001, when I retired. When I purchased it, I also purchased a Robland x31 combination machine. I have been an amateur woodworker for over 40 years, and until 2001, but during that time never owned nor used a bandsaw.

As well, I own a 1970s Delta Unisaw, a 1950s Delta Double-Arm Radial Saw, and recently I purchased a Hitachi 10-inch sliding compound miter saw, with laser light. And I have just rebuilt a 1950s vintage shaper/router (In the near future I'll post a file on the rebuilt shaper/router.)

Nonetheless, one of the most useful tools in my shop, the bandsaw can, like a table saw do most of my cross-cutting and ripping. It really shines, though, in resawing thick/wide stock or slicing off thin veneer, in cutting curves, circles, tenons, and dovetails like a jigsaw, scroll saw and/or tablesaw, in following templates like a router, and, uniquely, in sawing compound curves. Another asset of a larger bandsaw is it's (3hp or greater) more powerful motor.

Where the bandsaw lacks versatility, primarily because of its limited table size, is in ripping and/or resawing larger boards, and in cutting sheet goods. Limited table size (i.e., the bandsaw’s 18" “throat”) also limits its cross-cutting capacity.

I have heard that Europe’s equivalent of osha will not allow stacked dadoes, which means that, for dadoing and rabbetting, European craftsmen greater emphasis falls upon shapers and router tables, with a de-emphasis upon table saws. Take the capacity of dadoing/rabbetting away, a table saw’s other major attributes are cross-cutting and ripping, both tasks that also can be done on the bandsaw. In other words, you can make the case, as did Gary Rogowski, a Portland-based professional woodworker/teacher, in a recent issue of FW, that a bandsaw is a more important first purchase for woodworkers than a table saw. Would US woodworkers widely embrace this claim, at least to the point of making a bandsaw their choice for first purchase over a tablesaw? With enhancements of bandsaws, I believe they would. Already the market is breaking out of the 14-inch syndrome, and amateur woodworkers are, increasingly, purchasing 16-inch or larger bandsaws,

Now it is true that, in comparison with the polished cuts possible with, say, Forrest blades on the table saw, the quality of cuts on the bandsaw come up short. (Clean up of cuts can be done easily with the jointer and/or planer or performax-type sander.) On the other hand, safety considerations, like no kickback, and the narrower width of the kerf, which means less waste sawdust, give bandsaws specific advantages. But all of these issues are choices each woodworker makes, according to his particular likes and needs.

Taken together, many of the things mentioned above persuaded me that without enlarging the table of my bandsaw, its capacity for becoming a more central tool in the shop was limited. With that in mind, I began experimenting a little, and with experience, have arrived at the model for an improved table/fence/sled combo that you see in photos below. Improvements and/or changes are made as needed, though.

My table/fence cuts accurately, the set-up is quickly adjusted, and using the graphing makes everything easy to read, especially for repetitive cuts.

Costwise, it is difficult to estimate. The parts of the table/fence/sled that you see in the photos cost me considerably less than $100. For the table in this initial version, I used a half a sheet of birch 12-ply plywood, at $40 a sheet. The graph cost under $20. Everything else I salvaged from other items in my shop.

Blades for bandsaws:

Bandsaw blade drift presents a key issue to bandsaw users. As I've found in my own experience, each blade seems to have its own personality. In the picture below, notice that the fence sets perpendicular to the track on the infeed side. That's because this particular Lenox blade (2½ tpi) doesn't have a blade drift, and so I use it all the time.

Photo 1 shows for my Laguna 18 inch bandsaw, (1) an enlarged table, approx 48 x 48 inches, and (2) a fence that combines wood and extruded aluminum.

The fence consists of (1) a wooden part, that stretches across the table from infeed side to outfeed side, and (2) an adjustable extruded aluminum bar, about 4 inches high. The extruded aluminum fence attaches to the wooden part of the fence, roughly 4” x 1 ½” by 4’, with ¼ “ 20 tpi threaded bolts. The heads of the bolts slide in a groove in the extruded aluminum. The bolts are tightened with the black knobs, seen on the right of the wooden part of the fence in Photo 1.

As shown in Photo 3, the wooden section of the fence includes roller bearings to reduce friction. The fence itself adjusts in two ways: (1) the wooden section is adjustable for blade drift (the three bolts on wooden part of the fence on the infeed side allow fence angle adjustment) and (2) the extruded aluminum fence is adjustable before and after the blade.

Locking the fence in place is easy. Since the fence is on the right of the blade, on the infeed side, it only has to be prevented from sliding to the right, and this is done with a clamp (also part of the salvaged jig) screwed to the track that the head of the fence slides in. On the outfeed side, the fence is secured from movement by a "stabilizer bar" (the best view is photo 8) secured with a threaded knob.

The plywood part of the table is screwed onto a frame composed of oak pieces, roughly 1½ " x 1" x appropriate lengths. The 1½ " x 1" oak pieces that wrap around the bandsaw's cast iron table are attached to the table with 8 ¼" bolts, i.e., two for each side. This "frame" also extends around the outside edge of the table, giving sufficient support to the plywood. The combination of this frame and the 3/4 ' plywood create a strong table. ( A diagram would be ideal, but I am not good with illustrations. See Photos 14 and 15.)

On the top of the approx 48 x 48 plywood is an approximately 1/8" thick plastic "graph" and “ruler”. This plastic is included for a variety reasons, primarily to help in measuring for cuts and for adjusting for blade drift, but it also reduces friction. This plastic graph comes from a fabric store.

Tilting the table:

I don't "tilt" the table, but with difficulty, it can be tilted. With the sled, using different kinds of wooden "angle squares" that I've made myself, I can make a variety of angled cuts.

On the right of the table, note first, the two parallel miter tracks for a sled, and, second, the adjustable bar, for stabilizing the fence on the outfeed side.


In Photo 2, note the ruler on the infeed side and on each of the other sides. Useful for setting fence at regular increments for resawing veneer, or just resawing to width. Also note biesemeyer-like track mechanism for setting infeed side of fence.

This "track" I cobbled together from parts cannibalized from an elaborate jig, mostly extruded aluminum, for cutting plywood panels. I purchased this jig at a woodworking show, but found that when set up permanently, for the amount of use I was getting from, it ate up to much real estate in my shop.




In Photo 3, note roller bearings under fence. When I first installed fence, because of friction between fence and table top, even with plastic surface, maintaining the angle, whether a 90º or a special one for specific blade drift, was dicey. Now the fence moves with ease, but temporary "fillers" are needed in the tracks where the roller bearings pass over. The two parallel miter tracks are for sled.

Photo 4 illustrates the set-up for the featherboard(s). First, the track that the featherboards slide in is itself held securely in two parallel T-tracks perpendicular to the fence. Second, the slot in the track allows the featherboards to be set "before" the blade, and, if needed, "after" the blade, on the outfeed side of the table. The featherboards themselves are flexible; i.e., for ripping, one layer is sufficient, but if needed for resawing thick pieces, the height of the featherboard can be increased by adding needed layers on top of the base layer.






Photo 5 gives another view of the featherboard mechanism, including the black adjustable stop, on the outfeed side.(There is no Photo 6.)



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Photo 7 is the first of several that show the sequence of resawing a rough sawn piece English walnut. The bark is being saw off first, in preparation for resawing into veneer.




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Photo 8 shows the bark cut off, creating an almost square workpiece. However, the two sides are run through a jointer, to flatten the surfaces and make two sides square with another.



Photo 9 shows two things, first the half inch "slab" cut off the English walnut workpiece, and second, on the right outfeed side, the threaded knob for securing the stabilizer bar.

Photo 10 shows a caliper measuring the thickness of resawn veneer, 1/8" thick, or, as the readout for the caliper shows, one 133/1000ths of an inch. Cutting thinner veneer, to uniform thickness, is easy.

Photo 11 shows sawing timbers with the sled. Much more efficient than sawing with 10-inch table saw, skil saw, reciprocating saw, etc. Capacity for sawing timber is limited by the size of the bandsaw's throat, and, for longer and/or heavier pieces, capability of holding material steady while sawing. I could have photo that shows that the cut is square.

Photos 12 and 13 show 48 x 48 inch sheet of plywood setting on sled in preparation for cutting. Limited by size of bandsaw's throat, and ability to balance sheet on table. The set-up will saw accurately. The half sheet (i.e, 48 x 38 inches) is the unused part of the 4 x 8 sheet used for the table top.

In Photo 13, be assured that the table is level and square with the blade.


In Photo 14, above, but not captioned, the extruded aluminum track is attached to a board that, in turn, attaches to the front of the plywood table top. Without support, table top is weakened by blade slot. The board's purpose is to strengthen infeed side of table. (I think that for added support, two ¼” bolts, on eachside of the blade slot, need to be mounted.) Note threaded olt with black knob in Photos 2, 8 and 9. If further strengthening is required, to keep table from sagging with weight of workpiece, two additional ¼ inch bolts, one on each side of blade slot, could be added.

Photo 15: View of underside of table, showing framing bolted to bandsaw's cast-iron table. This set-up creates a very stable table. Also note that thetable-tilt mechanism is accessible.


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