orchorsol soundbox repair
Posted: Sat Jul 11, 2020 6:59 pm
I got a pretty mouldy orchorsol portable gramophone today that showed up on Facebook Marketplace, after cleaning the case the gramophone came up pretty well, the soundbox was a bit more of a challenge.
The main issue was with the rear flange that is used to attach the rear lifebelt on these soundboxes, although the main body of the soundbox is cast aluminium, this rear flange was pot metal so of course when removing the soundbox from the tonearm for the first time in decades it crumbled into several pieces.
I epoxied the pieces back together, it stood no chance of holding together for its original purpose but it worked as a template to make a new brass piece.
I didn’t have a single piece of brass thick enough for the flange so I opted to solder together a few pieces of thinner brass together, not ideal, but it’s better than pot metal!
With the pieces soldered together I spray painted over the original flange to create a negative of the shape it wants to be
Next followed a lot of lathe work with a lot of measurement checking with callipers, my lathe is a Drummond M Type treadle lathe from the 20s or so, a very fun lathe, but no digital (or analogue) readouts so always pays to have a digital calliper close to hand!
Next is nickel plating to help it look a bit like the original
And done, for now, a lot of work for a small part, the soundbox is rebuilt but the diaphragm is on its way out, it has become very brittle around the outside and I had to patch a section so the diaphragm will need replaced, if anyone has an Orchorsol diaphragm or a parts soundbox please let me know!
The main issue was with the rear flange that is used to attach the rear lifebelt on these soundboxes, although the main body of the soundbox is cast aluminium, this rear flange was pot metal so of course when removing the soundbox from the tonearm for the first time in decades it crumbled into several pieces.
I epoxied the pieces back together, it stood no chance of holding together for its original purpose but it worked as a template to make a new brass piece.
I didn’t have a single piece of brass thick enough for the flange so I opted to solder together a few pieces of thinner brass together, not ideal, but it’s better than pot metal!
With the pieces soldered together I spray painted over the original flange to create a negative of the shape it wants to be
Next followed a lot of lathe work with a lot of measurement checking with callipers, my lathe is a Drummond M Type treadle lathe from the 20s or so, a very fun lathe, but no digital (or analogue) readouts so always pays to have a digital calliper close to hand!
Next is nickel plating to help it look a bit like the original
And done, for now, a lot of work for a small part, the soundbox is rebuilt but the diaphragm is on its way out, it has become very brittle around the outside and I had to patch a section so the diaphragm will need replaced, if anyone has an Orchorsol diaphragm or a parts soundbox please let me know!