Rust hole in chain stay bridge

I've gone for the low-tech approach for now -

• rust inhibitor
  
• some frame repair putty on the way
  
• stripped the stays & same treatment too as was some bubbling there & was paranoid
  
• going to give it a spray in keeping with its beater status
  
  

It's a proper ratty 60 year old Mercian Superlight, so it's either going to be awesome or a death trap. If former I'll get the stay bridge sorted properly.

thanks all