Sewing machine table hinge upgrade

When I adapted a sewing machine table for a customer to fit her machine I noticed it had hinges with barrels that stuck up off the table.

Sewing table with original hinges

These might be a problem when moving cloth across the table under the machine.  I didn't have an answer at the time, but later I came across a sewing machine or card table hinge that would do the job.

This two-pin hinge (available from  Lee Valley Tools and Rockler) opens flat to 180 degrees.  The next three pictures show it in comparison with one of the original hinges.

Original hinge (top) with two-pin hinge (bottom)

From the side the barrel of the original hinge sticks up but the two-pin hinge opens flat

Underneath the original hinge is flat, but the two-pin hinge has a link and barrel sections

The new two-pin hinges were the same width but shorter than the originals and had projections underneath.  The recesses for the hinges needed to be filled to compensate and carved out to fit the projections.

Depth measurement

To mark the correct depth to chisel out I measured the depth of the hinge with a double adjustable square, then transferred this to a marking gauge.

Setting the marking gauge

The round blade of the gauge marked the edge of the folding top.  The corners of the section were cut with a razor saw before the waste was pared away with a chisel - first horizontally with the top clamped but protected with cardboard to prevent scratching:

Chiseling out the hinge recess horizontally

then vertically in the bench vise to get clean cuts:

Chiseling out the hinge recess vertically

The edge of the table was first carved from the top in the same way as the hinged top, then the table was laid sideways on trestles to cut away from the edge:

Hinge recess marked for chiseling with the table on its side

The top was supported on a trestle while the new hinges were screwed in place:

Hinges fitted showing crescents at each end of the hinges

The crescents of white wood showing at the ends of the hinges were filled, stained and coated with shellac.

Crescents filled, stained and coated with shellac

A polish with paste wax completed the job to make the top nice and smooth.