Sunday, December 31, 2017

Happy New Year 2018

New Year's Eve is upon us, and I just want to wish all of you a happy New Year.

2017 was my second full year of retirement and was better in a couple of ways than the first year.  The biggest was that the year was free of medical issues like my emergency gall bladder surgery in June of '16.  It was largely a year of doing what we felt like doing - the privilege of retirement.  We took two vacation trips, one to South Dakota for a week with the kids and Precious Grand Daughter; the other to Tennessee to see the eclipse and they met us there.  We currently don't have anything planned for 2018, so it's getting to be time to plan something. 

Retirement is a relatively new concept in society, at best a couple of hundred years old, and it's evident that society (in some sort of nebulous, society-at-large sense) is having troubles with it.  See "underfunded pension plans" with your favorite search engine.   

I was looking at last year's blog entries to see what I was doing a year ago, and most of my posts were about completing the CNC conversion of my Grizzly G0704 - a year ago this weekend, I was completing the plumbing for the oiling system.  I also pointed out traps and tripwires that Obama was leaving for Trump.  We've encountered some of them as the year has gone by.

I had the mill built into a functional mill, completely under CNC control by February 2nd.  That quickly turned into a couple of months of tweaking and  improving.   First was reducing backlash on each of the axes, followed by completing an enclosure made from 12mm aluminum extrusion and plastic panels from the local Borg (mostly the blue Borg, not the orange).  And no, I don't know where that nickname comes from, other than I think it was the old Usenet newsgroups (kids, ask your parents).

I can't say I was done, because as recently as a few weeks ago, I talked about improvements to the rotary axis I originally added last May.  I can still think of things to do to improve its usability and user friendliness.  Then came adding an oiling system, fighting leaks until I went over to manual oiling, and finally adding a misting cooler.  It's probably best to never think of a project like this as done.

Then, of course, there was my "Son of Side Project".  Originally, Side Project was a joke because the project was putting a new side on the sawed away Breedlove guitar.  The original side was plastic left over from making the mill's enclosure.  Son of Side Project was a sequel to Side Project to replace the plastic with wood.  Now, it has a quilted maple side where the plastic was.  I gathered up the tools to do a setup on it this week and now it plays quite a bit better.  The guitar was most likely a Quality Control reject, so it needed lots of work.  The frets were uneven and had to be leveled with a file.  It probably needs some additional work.  I know the $8, eBay-special tuning machines I bought for it need to be replaced. 

As far as projects with my CNC'ed, four-axis G0704 mill, I haven't accomplished much.  I built the GB-22 but never got it to function reliably.  It's still sitting as a "one of these days" project, in pieces.  I built the Little Machine Shop wobbler steam engine.  After drilling out the flywheel on my rotary table, I took the whole thing apart and put a shinier finish on all of the parts by lapping them on finer grits of sandpaper, and/or turning in the lathe's chuck.  Put it back together to find it doesn't run as reliably as it did.  I think I took too much mass out of the Flywheel.  I will turn a new one and get it back to where it was. 

In addition to my ham radio antenna project, I have another electronics shop project, a box for a component called a variac.  This will allow me to put lower voltages on older vacuum tube equipment, at least while I get it running the first time. 
The black rectangle on the top is an AC voltmeter/ammeter like one of these and the AC outlet on the front is still under consideration.  This is going to be like my controller box for the CNC 704, with the panels laid out in Rhino3D CAD and cut out on the CNC mill.  This time it will be cut out on the big system, though.

Aside from those two, I'm looking at more projects for the metal shop, with fewer involving guitar resurrection.

Happy New Year!  Remember, if you drink, don't text and if you text, don't drive.  Or something like that. 


  1. You could put a stepper motor drive on the variac, reduction gearing with a toothed rubber timing belt. No, I don't know what you would use that for. Maybe CNC electroplating or etching with a probe, something where the current has to vary with the area or separation distance, which changes by CNC. CNC EDM.

    I think "retirement" means you have ascended into a post-scarcity society and you no longer have to work for a living. However, it doesn't mean you no longer have to work, as meaningful work is necessary for human happiness. Here are suggestions for projects which I would love for you to work on:

    Voice encryption for cell phones and half duplex radios. A little box to process audio. Does crypto against a one-time pad on a thumb drive, so a half duplex radio doesn't have to do a key-exchanging handshake or have fancy synchronized clocks, and it can broadcast many to one. Offered as a kit with cell phone headset connectors.

    Portable software defined radios with crypto built in. Lots of extra CPU cycles for tinkering. SDR to take advantage of newer modems which don't fit through existing FM. Two radios, VHF to similar VHF with no repeater, and HF for NVIS. Offered as a kit, to transfer regulatory liability to builder and meet whatever the equivalent of the 80% receiver rule is for the FCC.

  2. Couple of suggestions for what they are worth:

    1. Fuse both the input and the output. If only one fuse make sure it's on the output. I learned the hard way many years ago that a short on the output with a low setting for output voltage will burn up part of the winding without taking out a fuse on the input. GenRad versions use fast blow fuses.

    2. Consider installing a meter for volts/amps/watts rather than just volts/amps. Often nice to have real power and small digital meters that give all three measurements are readily available at low cost on eBay.

    Happy New Year!

    1. Thanks for that input. I was going to put a fuse on the line input side, but not both sides. I'll take a good look at that. It should be relatively easy to add.

      The variac I have is an eBay special and it has no markings for current or power ratings. I just think of it as 0 to 130 on the output - my main use will be to bring up some old gear with a lower line voltage. I have a Kill-A-Watt meter that can tell me the power draw in watts but without ratings, it's hard to know when to turn it off.

    2. You are very welcome! Definitely fuse the output. All of GerRad's packaged Variacs are done that way given that Io x Vo roughly equals Ii x Vi due to transformer action. You can find schematics at eDebris if you're interested. A Kill-A-Watt is a good solution when you need to know real power.

    3. I should have added that a model number, if you can find one, may give you a clue as to ratings. Been a while, but a number at the end usually gives the maximum rated current, input and output. If you have nothing, a core roughly 4" in diameter typically was 5 ampere capable. A core closer to 6-7" in diameter typically was good for 10 amps. 400Hz models were smaller, but yours looks like a 60Hz model.

    4. It's close to a 4" core - around 4.15 - but I recall the opening in the sheet metal had to be 4.72". There's a lip that's about 1/16" bigger diameter than that and I don't really have calipers with jaws long enough to directly measure it, so I was sweating it. The variac sits on the lid on that lip but clears the inner rim I needed to clear.

    5. You probably have a 5 amp model. I checked a loose Variac sitting in my shop. It is rated for 120V 10A at 50/60Hz. The model number is W10 and the core is close to 6" in diameter.

      I've probably beaten the subject about to death by now so I'll sign off by wishing you the best of luck with your project. As you have already noted, Variac's are great tools for troubleshooting stuff with power supply problems or for gently powered up equipment that's been sitting for a while, tube stuff particularly. Can't prove it, but I believe I've re-formed more than a few sketchy electrolytic caps by taking a half hour or so to gradually bring up long idle gear.