GIY (Grind It Yourself) precision film capacitor

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
This morning I was about finishing my active crossover, thought the needed 8 pcs. of 68 nF 1% film caps were in the parts bin. I only found 7. Dang! Fumbling with lots of caps in parallel and series to achieve 68 nF, no hit. Bleeding hell!

Necessity begets ingenuity: Picked a 100 nF Wima MKS4 and a piece of sandpaper and grinded the cap from the top. It took some strokes to get through the plastic coat. And then measuring it with the c-meter, getting around 99 nF, grinding, measuring 93 nf, grinding ... I ended with 67,87 nF.

The reason why that works is obvious:

An externally hosted image should be here but it was not working when we last tested it.


And now back to soldering!

Cheers,

Gerd
 
If you're going to keep it that way, seal the end with fingernail polish. Water has a way of changing things over the years. Nearly as creative as the steering idler arm retaining nut I made last week. Or, I could scrap the car and buy a new one, computer, air bags, and paper body.
 

Attachments

  • grinded_cap.jpg
    grinded_cap.jpg
    568 KB · Views: 160
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.