Rubber Flashing

Jim Morgans Wood Profits

Wood Profits by Jim Morgan

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the work. On a one-part form, use cauls to further distribute clamping pressure, spacing them no more than 3 in. apart. (See lead photo.) For laminations over 5 in. wide, use clamps in pairs to hold the cauls, and crown the cauls a wee bit with a hand plane or jointer so they exert pressure at the center as the clamps pull the ends of the cauls tight. (Sec drawing.)

To prevent glue from sticking the wrong parts together, wax the faces of the forms and any cover layers. A coat of shellac also works, or you can insert sheets of waxed paper.

Clamping can take perseverance. With two-part forms, the amount of movement needed to pull the laminates to the form may exceed the range of the clamp screws. In this case, draw the laminates partway down with one set of clamps and the rest of the way with another set alongside the first.

An alternative method of clamping is to use a vacuum press. This is best for gentle curves, and is excellent for wide workpieces such as cabinet sides or door panels, because the clamping pressure is very uniform. In a vacuum press (see Sources, next page), the laminates and a cover layer are temporarily taped to the form (duct tape works well) and the assembly is placed in a sealed plastic bag. Air is sucked out of the bag via a vacuum pump, and atmospheric pressure presses the laminates to the form. (See photos, next page.)

Your choice of glue for bent lamination depends on the length of time you'll need for open and closed assembly, as well as any requirements for water resistance.

So far, yellow polyvinyl acetate (PVA) glue has worked well for me through a variety of situations, and I like its nontoxicity and ease of cleanup. I use a slow-set PVA (see Sources) to give me ample time to get all the parts together before the glue sets. However, many woodworkers I know prefer epoxy or plastic resin (urea-formaldehyde) glue (see Sources), lw>th of which have a longer working time than regular PVAs. Also. PVA glues have been known to creep slightly at the glue line over time, making the edge of the work feel rough to the touch.

Resawing on the Bandsaw

I use a simple right angled fence screwed together from scrapwood and plywood (see photo, below) that I clamp to my bandsaw table. When building the fence, make sure the face is perfectly square to the bottom so that, once clamped, the fence is square to the saw blade. Positioning the fence for resawing can be tricky because most handsaws rarely cut parallel with the edge of the saw table. Instead, the blade persistently wanders in its own direction, a phenomenon called drift. To compensate for this, the fence must be angled in the direction that the blade wants to cut.

To "set the drift," mark a line along the top of a straight board, parallel to the edge. Saw along the line, rotating the work-piece until you find the "angle of approach" (where the blade follows the line exactly), then stop, hold the wood in position, and record its angle to the bandsaw table with a bevel gauge. (See photo, above.) Use the bevel gauge to align the fence at the same angle, and clamp the fence at the desired distance from the blade.

Resawing is more accurate when you use a sharp blade and a simple shop-made fence.

To resaw, mill your stock four-square (all four sides square to each other) and make sure your blade is square to the table. Make a test cut on some scrap, then resaw the first piece, holding the work firmly against the fence. Push the board through the saw at a steady rate that doesn't slow the blade or tax the motor. Then resurface the sawn face of the stock on the jointer, and resaw again. For safety, use the thickness planer to clean up the sawn side when the stock becomes thinner than l/? in. or so. —P.K.

Resawing boards into thinner strips on the bandsaw wastes very little wood, which makes it a good method to use when you need to saw laminates for bent lamination. (See main article.) With a shop-made straight fence and a sharp blade, you can easily resaw stock as thin as Vie in., if you follow a few simple techniques.

I generally use a x/2-in. four-tooth hook blade for most of my resawing, although some woodworkers use skip-tooth blades with good results. (See "Choosing Bandsaw Blades," page 45.) Regardless of the type of blade Author saws along a straight line to determine the you use. make sure "drift" of the blade, and then records the angle with a it's sharp. bevel gauge.

Before gluing the laminates, it's best to dry-clamp them to make sure you have everything in order. Then spread a thin, even coat of glue on both sides of each glue joint. I find the best tool for spreading glue is a 3-in. paint roller with a low nap.

Once you've spread the glue, clamp the work to the form as quickly as possible. With the laminations slipping around and the resistance of the wood to bending, you'll probably want an extra pair of hands around. Keep the lamination stack aligned edge-to-edge as best you can, but rest assured, you'll never keep it perfect.

Dimensioning the Lamination

The layered edges of a new lamination are uneven and usually covered with dried crusts of glue. The first

thing to do is remove as much of the surface glue as possible with a paint scraper so it won't dull your tools.

To dimension your laminated part, you'll need to create a straight edge on the part. The best method I have found is to sweep the work over a jointer. (See photo, below left.) Once you have a straight, square edge, you can rip the opposite edge parallel on the tablesaw. (See photo, below.) An alternative is to use the handsaw: Mark the width with a flexible straightedge or a marking gauge, then handsaw to the line, pivoting the workpiece on its curve to keep it in contact with the table at the blade. Clean up any machine marks with a hand plane.

Bent lamination is a simple technique that opens up a wide range of

To square the edge of a curved lamination, first use a jointer (left), taking light cuts and keeping the outside face against the fence near the cutterhead. Then rip H to width on a tablesaw with an auxiliary fence. Use a feather board to steady the workpiece, and a push stick at the end of the cut to keep your hands clear of the blade. The tablesaw's splitter helps prevent kickback.

To square the edge of a curved lamination, first use a jointer (left), taking light cuts and keeping the outside face against the fence near the cutterhead. Then rip H to width on a tablesaw with an auxiliary fence. Use a feather board to steady the workpiece, and a push stick at the end of the cut to keep your hands clear of the blade. The tablesaw's splitter helps prevent kickback.

Author uses a vacuum press to clamp laminates onto a one-part form. The work is placed inside the bag (left) and the vacuum pump on the floor sucks the air from the bag. Atmospheric pressure holds the laminates (above) tightly to the form.

design options. It combines the natural bcautv of wood

with modern adhe-sives to enhance the grace and strength of your work. ▲

teaches workshops in Rockland, Maine. He is the author of Working with Wood: Pjc Basics of QiiftSimimfM (¡993, Taunton Press, Box 355, Newtown, CT06470).

Glues for laminating are available from the following sources:

Garrett Wade

161 Ave. of the Americas New York. NY 10013 (800) 221-2942

Circle #657

Gougeon Brothers Inc.

Box 908, Bay City. Ml 48707 (517) 684-7286

Circle #658

Okie Mill Cabinet Shoppe

1660 Camp Betty Washington Rd. York, PA 17402 (717) 755-8884

Circle #659

Vacuum prossos arc availablo from the following sources:

Mercury Vacuum Presses

Box 2232. Fort Bragg. CA 95437 (800) 995-4506

Circle #660

Vacuum Pressing Systems Inc.

553 River Rd. Brunswick. ME 04011 (207) 725-0935

Circle #661

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Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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