Wednesday, January 27, 2010

slowly I returned, step by step, inch by inch...

Since I started being more careful with where I allow pressure to be applied to my hands (at work), pushing fluids and NSAIDs, and taking a break from my home workshop, my hands (and more to the point, the tendons therein) have finally begun to feel a bit better. I shall continue the regimen.

Meanwhile, I have begun a cautious return to my workshop, allowing myself to do light tasks such as:

1. cleaning off my workbench

2. improving the organization of my hand tools (which includes removing anything that is not a hand tool from the pegboard at the back of my workbench to make more room for actual tools)

3. setting up for a high voltage breakdown test in the capacitor from my previous post. That must be done with some care, as the voltage may have to be raised quite high to find the breakdown voltage of the capacitor. That means taking up a lot of space for safety. And that is what lead to #1.

4. cleaning and tidying up the shop in general - we're going to be hosting the February Mad Scientists Club meeting, and I want to make some progress on a few minor projects between now and then. It's time we brought back the show-n-tell that used to be common at these things. Also, the shop is a mess.

A bit on the breakdown test of the odd wax-filled capacitor: the test will be done in such a way that any short-circuit current will be limited to some microamps. I am blessed with a fair collection of ridiculous value high voltage resistors with fairly precision values (example: 990 MΩ, 0.3%) which should make that relatively trivial.

I'll measure the (DC) current directly through a 100µA meter movement. I don't believe I am likely to damage the insulation under such conditions.

I haven't a ready-to-hand DC high voltage supply above 5.5 kV, so I will have to jury-rig something out of parts. Nothing I haven't done before.

Gee whiz I wish I hadn't let that non-current-limited laser power supply transformer (16kVAC) slip through my fingers a few years ago...

No comments: