Retapping Agraffes

[David ilvedson]

List,

I have a fellow piano technician here in the bay area who has a 
problem for your consideration.  He has a no-name (Girard or 
something like that) grand which he is restringing.  He would 
like to replace the agraffes (non have broken in the past) but 
has found that the originals are in between the 1/4" and 7/32" 
sizes.  His question is can he just tap whats there with a 1/4" 
tap or does he need to drill it first?  Should he just stay with 
what he has?    

Thanks in advance...

ilvey
Pacifica, CA
ilvey@a.crl.com