Roll Your Own Capacitors

From Popular Electronics, over 61 years ago:

http://www.who.int/water_sanitation_health/hygiene/emergencies/fs3_4.pdf

It is also possible to make a DIY toilet.

Both skills are handy to know and have. Especially for the "whys" that go into them. I find that hand-on experiences are far better at conveying what the theory implies than any other method.

At which point I will stop for fear of making a political remark.

That's all a cap is - two plates separated by a dielectric. Good learning experience but would be nervous with 400V across something I rolled up. Think I will stick with store bought caps.

"It is also possible to make a DIY toilet".

I'm not sure about that one.
Back in the day in my more creative days. I tried to make one anatomically correct that worked, and for a moment I thought I had it.  Oh was I wrong !!! The whole darn thing collapsed in the middle of a " download" !!!

I was kinda-sorta going in that direction when I saw the part about dipping the whole shebang in paraffin at the end of the process. Paraffin does absorb small amounts (very small, but significant) of moisture, and that property is one of the contributing reasons to why vintage paper/wax capacitors fail.

What is surprising is that this property was observed in the 1930s with vintage paraffin-dipped radio coils failing in large quantities, but manufacturers still went ahead and used it into the 1950s. Cheap.

Note that as an insulator, paraffin is almost as good as Mylar - until it isn't.

I remember in my High School science class taught by a first-class curmudgeon and eccentric, we made gunpowder the old-fashioned way that included saving our urine for the nitrates (Civil war style), rendering oak for charcoal, but using sulphur from the lab. We also made Nitrogen TriIodide (AKA Contact Explosive), gun cotton (cellulose + Nitric Acid + hydrochloric acid) and all sorts of other 'stuff'. His theory was "in the case of all hell breaking loose, these things are good to know."

Peter W. wrote:I remember in my High School science class taught by a first-class curmudgeon and eccentric, we made gunpowder the old-fashioned way that included saving our urine for the nitrates (Civil war style), rendering oak for charcoal, but using sulphur from the lab. We also made Nitrogen TriIodide (AKA Contact Explosive), gun cotton (cellulose + Nitric Acid + hydrochloric acid) and all sorts of other 'stuff'. His theory was "in the case of all hell breaking loose, these things are good to know."

I'm still stocking up on factory ammo.

I was reading a few months ago about the virtues of wire wound resistors, and how some in the DIY audiophile community are winding their own at home. Sounds a bit tedious to me, but, hey, maybe we could have an Uber DIY challenge. I'd be willing to kick in to a pot that would be claimed by the forum member who makes the most DIY of diy VTA ST XXX amps. Roll your own caps, resistors, trannies anyone?

Tube Nube wrote:I was reading a few months ago about the virtues of wire wound resistors, and how some in the DIY audiophile community are winding their own at home. Sounds a bit tedious to me, but, hey, maybe we could have an Uber DIY challenge. I'd be willing to kick in to a pot that would be claimed by the forum member who makes the most DIY of diy VTA ST XXX amps. Roll your own caps, resistors, trannies anyone?

Wire-wound resistors are also pretty effective as inductors. Of course, it would depend on the conditions and locations involved. But I would be wary of certain applications and locations.

You're in luck, Pete, here's a link that teaches you how to roll 'em so they don't "react".

Tube Nube wrote:You're in luck, Pete, here's a link that teaches you how to roll 'em so they don't "react".

Noob, no link. Could you re-post?

deepee99 wrote:

Tube Nube wrote:You're in luck, Pete, here's a link that teaches you how to roll 'em so they don't "react".

Noob, no link. Could you re-post?

Sorry, Dave,

Let's try again:

http://www.resistorguide.com/wirewound-resistor/