diy capacitors

RnFR · Post by **RnFR** » 24 Nov 2009, 12:23

looks interesting!

http://www.elisanet.fi/dncmrc/rolled_cap.htm

http://www.linux-host.org/energy/scapacit.htm

http://www.instructables.com/id/Flux-Capacitor/

Jarno · Post by **Jarno** » 25 Nov 2009, 19:15

This guy in Israel built his own 60' Jazz Bass, right down to the PIO cap, check it out: TDPRI.com thread

Anyways, it looked so easy that I didn't think it would work, so I tried myself

I glued aluminiumfoil strips onto paper strips, rolled them, and soaked them in mineral oil (the stuff they use to lubricate sewing machines).
First try:

Not very successful, because the alu foil shorts, I did get enough capacitance on the meter to make me want to try again.
Try and try again:

620nF! Not bad, it does leak a bit (DC resistance 1,5M) so I wouldn't use it in a tube amp. Also, sealing is important, I left it hooked up to the meter unsealed and checked every couple of days, as the oil leaked away, so did the capacitance.

RnFR · Post by **RnFR** » 26 Nov 2009, 12:19

wow Jarno, that is quite a thread! thanks for the link and the pics of your experience giving it a try. do you think you'll ever try actually potting one fully and finishing it off? and do you know how to adjust the amount of capacitance?

Jarno · Post by **Jarno** » 26 Nov 2009, 14:29

You mean the build thread of that Jazz Bass? Yes, that is one dedicated guy right there!

I am not sure I will be potting diy caps anytime soon, although I am curious to see if they sound different/ better. You can adjust the capacitance by either the distance between the conductors, the surface area and the dieelectricum (in my case paper). I have found formulas to calculate the capacitance of flat plate capacitors, but my second test ended up much higher, so there is probably a different set of formulas involved.