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Double-Duty Edge-Gluing Clamps


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HIS SHOP-BUILT EDGE-GLUINGclamp performs double duty. It is
not only a terrific bar clamp, but it also aligns the various work-
pieces being glued, thus eliminating the need for a separate alignment
“sandwich” made with scrap and C-clamps.
The clamps consist of two yokes and two notched wooden bars.
Each yoke assembly has a pair of trapeze-like arms made from 8-in.-
long pieces of strap iron that pivot on the sides of a block made from


(^3) ⁄ 4 -in.-thick mild steel. Drill and tap a hole through the block to accept
a^1 ⁄ 2 -in. threaded drive rod. Then, drill and tap^1 ⁄ 4 -in. holes in the sides
of the block to bolt the arms in place.
Next, screw a length of^1 ⁄ 2 -in. threaded rod through the block and
attach a knob or crank to its outboard end. To distribute clamping
pressure, make a wooden caul with a shallow^1 ⁄ 2 -in. hole bored in its
edge to locate the end of the rod. Plane a shallow concave curve in
the caul edge that contacts the work to ensure even distribution of
clamping pressure.
Cut the clamp’s notched wooden bars from 1^1 ⁄ 4 -in.-thick sticks of
hardwood. The bars should be as wide as the space in the yoke arms.
To make sure the notches in the bars are perfectly aligned, cut both
bars at the same time with a^1 ⁄ 4 -in. dado blade.
—WILLIAMSWA RT Z,Modesto, Calif.
CHAPTER NINE
Notched bar
Yoke arms Caul
A^1 ⁄ 2 -in. threaded
rod moves
through
the drive block.

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