Original poster: "D.C. Cox" <resonance@xxxxxxxxxx>The green SDR (sewer & drain) works very well as it's thin-walled for lightweight secondary and, well, . . . . . it's gr-e-e-n!! Megs out very well on our solid state megger. The black doesn't do very well --- might begin conduction at the right potential.
Someone also had a question on proper sec coil elevation for both 4 inch ID and 6 inch ID white PVC tubes when used as a sec coilform. Use dual interior baffles --- one 5 inch down from top and one 5 inch up from bottom. Silicone in place with GE Silicone II clear.
For 4 inch ID use 1.75" above horizontal plane of primary and for 6 inch use 2.25 inch elevation. Use a 2 x sec coilform dia toroid dia with a min. of 4:1 major dia to min. dia ratio on the toroid. You can also use up to 3x or 4 x if you plan on using a large pri cap and have a lot of driving power available, ie, 180-250 mA. 2 X works great with either 60, 90, 0r 120 mA driving power. With this coupling setup --- No racing sparks --- ever!!
Dr. Resonance
After burning a nice hole in my secondary I went to home depot to find a piece of pipe for a replacement form. A came home with a hunk 4"x24" of black ABS. I've searched through the archives and have read mixed opinions about black ABS. Someone suggested that rubbing it on paper would be a good test to see if it contains carbon. What I have is very hard and leaves no mark. The other suggestion is to rub in im my hair to see if it generates static. I shave my head, so my shiney head precludes me from running that test! So what do you guys think? Would this stuff be OK, or should I pitch it and get a hunk of white PVC? Are there any other tests I could run? Thanks, Curt.