New parts made and Reassembly

New theme flap valves are made exactly like the old ones.

Regulators are recovered.  All old glue is sanded off first.

The main portion of the expression box must be baked in the oven in order to be popped open.  This is a very delicate job and is not for the novice to do.  On this one there was minor splintering,  Early ones I redid REALLY splintered.  All splinters must be glued back into place.

New valves are made from the same piano hammer trimmings as what the originals were from.  New motor cloth and leather and fiber disks are glued together exactly like the factory made them.

The new pouches and valves are installed and the box has a gasket made for it to prevent another restoration from being as difficult as the first time is.  Remember in 60 or more years these pouches may need replacement again.  Inside surfaces are coated in shellac except where glue will go.

When put back together more screws are added for the gasket we installed.

All is reassembled and new muffler felt is installed around the spill valve chamber seen in lower right corner.

Regulators are glued back on with new gaskets.  Three screws hold on each regulator but gluing is necessary here as the factory did.  Elbows to the stack are taped up and 5/32" nipples are used to puncture the tape for testing purposes.

The unit is all reassembled and tested and ready to return to the piano.  With correct testing and regulating the unit will not need zero level screws touched once in the piano.  The two springs may need minor adjustment and the felt in the spill hole will need fluffing or pressing to adjust lowest volume playable.  Piano must be well regulated to get soft playing from your restored Duo Art.

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