Edison Class M speed regulator replica
Posted: Tue Apr 27, 2021 4:57 pm
Hi all,
I'm sharing for your enjoyment a nice restoration I finished a week ago.
A customer from Canada sent me an email asking if I could make a replica of an Edison Class M speed governor. He was restoring one and that vital part was missing.
By luck, I had at the workshop another Class M so I was able to take all the measurements of the casting of the frame and al the pieces of the spindle and brushes. We agreed to make the piece in brass because its impossible to cast it in iron on a small foundry and he asked me not to paint it because he will paint is with asphaltum (also known as japaning)
I have some experience making patterns, moulds and brass or aluminium castings but the intricate shapes of the piece required several attempts until I figured out the optimum position of the pouring cup, raisers and runners in the sand mould.
This was the firs attempt. As you can see, the brass did not fill completely the mould:
With more and thicker runners I managed to make a decent casting:
After many hours of filing and filling with silver some very minor imperfections, I arrived to this (Side by side with the real thing):
Then, it was time to power up the lathe and make all the different screws, governor balls, contactor ring and pulley:
Finally, I made the external ring, brushes and nickel plated the required pieces:
Today I received a very nice email from the customer showing the governor painted and installed:
I hope you enjoyed the little article as much as I enjoyed this project!
Regards
Pedro Martinez
www.pedrofono.es
I'm sharing for your enjoyment a nice restoration I finished a week ago.
A customer from Canada sent me an email asking if I could make a replica of an Edison Class M speed governor. He was restoring one and that vital part was missing.
By luck, I had at the workshop another Class M so I was able to take all the measurements of the casting of the frame and al the pieces of the spindle and brushes. We agreed to make the piece in brass because its impossible to cast it in iron on a small foundry and he asked me not to paint it because he will paint is with asphaltum (also known as japaning)
I have some experience making patterns, moulds and brass or aluminium castings but the intricate shapes of the piece required several attempts until I figured out the optimum position of the pouring cup, raisers and runners in the sand mould.
This was the firs attempt. As you can see, the brass did not fill completely the mould:
With more and thicker runners I managed to make a decent casting:
After many hours of filing and filling with silver some very minor imperfections, I arrived to this (Side by side with the real thing):
Then, it was time to power up the lathe and make all the different screws, governor balls, contactor ring and pulley:
Finally, I made the external ring, brushes and nickel plated the required pieces:
Regards
Pedro Martinez
www.pedrofono.es