Blind wedging joint

(Jigoku hozo)

This model was also splii in half.

This joint is commonly used on eave brackets, hanging posts of lintel and whenever the tenon and mortise are better left hidden. To assemble this joint, two wedges are loosely driven in the tenon. The tenon is then inserted in the mortise and driven in. The wedges hit the bottom of the mortise, opening the tenon like a fan and locking it permanently. Experience is important in manufacturing this joint. The tenon is always cut a little bit shorter than the depth of the mortise to insure the element being assembled is fully inside before the tenon wedges itself permanently. Some techniques are helpful for assembling the joint success fully. The inside of the mortise must be clean and blown free of any debris. Sometimes the joint is splashed with water after inserting the tenon into the cavity.

Housed dovetailed joint

(Okuri ari)

This joint is frequently used on hanging posts (tsurizuka). At first the dovetail is inserted in the larger opening of the mortise (area A) and then shifted sidcway into the narrower slot (area B) which has the exact inverted shape. Finally a wooden plug is set to ensure the joint will not easily come apart. Sometimes the dovetail is cut in half along the depth of the male end. The assembly proceeds as mentioned earlier. The larger opening of the mortise (area A) is now hidden by the male. The latter form

Male Female Dovetail Joints

of this joint can be used to anchor the legs of shelving units on a floor.

Male Female Dovetail Fitting

O Male and female

0 The dovetail slides into the bigger end of the mortise.

O Male and female

0 The dovetail slides into the bigger end of the mortise.

Same

O The dovetail is shifted into the smaller end of the mortise.

Same

O The dovetail is shifted into the smaller end of the mortise.

Assembled joint

The plug is not shown for clarity.

Assembled joint

The plug is not shown for clarity.

A

II

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ri • •

: *

w • • • >

r—

; j

L—

f

Sumiyoshi double tenon

The upper tenon is a dovetail with «ring side walls. The lower tenon is rectangular with one surface tapering up. The joint is assembled by sliding the double tenon upward into the mortise at the same angle as the tapered surface of the lower tenon. Master Sumiyoshi learned of this joint from fellow craftsmen. An X-ray picture of the assembly shows some discontinuity Swing it not entirely satisfactory.

X-ray photograph showing a discontinuity after assembly

The lower tenon appears completely white suggesting an imperfect fit. White gaps can also be seen on the left and right side of the tapered tenon. A perfect fit after assembly ensures the integrity of a joint.

Sumiyoshi Double Tenon

O Assembled joint

O Assembled joint

CONNECTING JOINT 06

Double plug assembly before inserting pin and keys, otherwise the components could be exposed to excessively large stress.

This assembly connects two beams on opposite faces of a column. The beams are spliced through the column. Larger splices (pole tenon) produce sturdier assemblies. The beam with the longer tenon is connected to the column first. The second beam is inserted and shifted forward until the lower tenons butt at the centre of the column. The connection between the beams and the column is completed before finishing the splice between the beams. In order to provide the joint with enough tensile resistance, two keys and a draw pin arc driven in. One or the other would be insufficient by itself. It is important to tighten the

Japanese Beam Splice

0 Beam 1 is inserted through tho column

After tightening the joint, two keys are inserted.

A draw pin completes the assembly.

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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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