Aeolian Orchestrelle Bellows Cover and Pressure Relief

Hello,  We are scratching our heads about a few of the parts on our
Model Y Orchestrelle that we are restoring and are looking to see if
anyone on MMD can help us with a few questions.

Attached are two pictures.  Picture 1 shows the cover for the front
paddle of the bellows.  On one cover there is a hole and a pallet
mechanism which appears to be a pressure relief.  When we received
the unit it had a piece of string attached to the inside of the
bellows and at a certain point in the travel of the paddle the string
would pull this pallet open and dump pressure.

We are unsure if this is original or not, as in Picture 2 there is
a mechanism which had been blocked off inside the bass chest.  This
part seems to have been connected via a linkage to the front of the
paddle.  The pallet shown in the picture lives inside the box and is
operated by the rod at the top.

It looks to me as if this part was the original method of dumping or
regulating pressure, and the hole in the front cover of the bellows
is either a secondary system or has been put in at a later date due
to parts of the original linkage being missing.

We would be grateful for any advice on this. We need to re-veneer the
front cover shortly and need to know if we should block the hole up
or leave it as it is original.

Thanks,
James

 [ http://www.mmdigest.com/Attachments/18/05/11/180511_021506_Picture1.png 
 [ http://www.mmdigest.com/Attachments/18/05/11/180511_021506_Picture2.png