sobota, 8 listopada 2014

Restoring Ruhmkorff induction coil.



Restoring Ruhmkorff induction coil. 




     This post is dedicated to any one who would like to learn how to restore Induction Coil.
This restoration I base on my new coil which I was lucky to buy from eBay.
It is over 60 years old Ruhmkorff coil ,which use to be used in local University to demonstrate 
electromagnetic induction .
     This coil has some think special to it, it was made in the same day and the same month I was born
24.06 but many decades earlier .
When I bought it ,it was badly neglected , and needed urgent attention and the coil didn't produce any sparks what so ever. 
The next think to do was take the coil apart and dismantle it piece by piece.
That was first step to my small restoration project :) "Ruhmkorff Coil" 




First steps:
Clean all brass and metal pieces with wool wire and then polish them with brass polish.
Just to polish every single piece include:nuts,bolts it took me few long evenings but with this restoration there was no short cuts every metal piece must have mirror shine :)


Gently restore wooden base:
After removing few years old dust from the base I could see that it wasn't to damage so I decide to give it gentle restoration with scratch removal and finish of with special oil.
On photo below you can see left half base cleaned up and right side unrestored.



Polish every single brass piece :
That was most time consuming part of the restoration but give me lots of pleasure to make all the small bits of metal shine back again.Every bit was polish only by hand!
But the end effect was worth the effort :) 



Left photo show brass parts before restoration and the left after polishing. Despite my best effort 
this picture can't show how much it shine, in every piece I can see my self :)

Shine on !


Photo below show internal parts of my Ruhmkorff coil:
-0.5mF Capacitor 
-few connectors 
Unfortunately capacitor was to old :) to be use again,by the way it is one of the most important parts of this scientific instrument. There was no other way to fix it but replace it.


They are just examples of caps which I used to find the best one because I couldn't find direct replacement for 0.5mF 250V DC so I need to improvise.


With the right capacitor and all parts in palace I could finely connect power supply and please my eye with some wonderful sparks and luminous effects :) 


One more time just to remind how the scientific instrument was look before and after 
RESTORATION :) 



Video of my working Ruhmkorff coil:





Regards