Thursday, January 1, 2009

What Every Woman Wants (No, Seriously!)

I've got what every woman wants.

It's due to the Dexamethasone of course. ('Dexy' to the trade.) Dexy is one of those horrifically potent steroids that flat EATS cancerous tumors. Along with everything else, alas. Which is why I've managed to shed a few pounds, going from a chubbily pleasant 254 to a cadaverous 171.

I've no way of knowing how much of that 83 pounds consisted of tumorous tissue. And there at the start, following LAST New Years, I promised myself it was time to shed a few pounds and did, which got me into the 230-ish range, at which point I was diagnosed with multiple myeloma and began the more serious business of chemotherapy, which whisked away the pounds, along with patches of hair (it's coming in CURLY, of all things!) and tumorous tissue.

But I now possess what every woman wants: To hear a physician say: 'It's time for you to put ON a few pounds.' And I thought of all the women I've known without being able to recall a single one of them who was not wishing just the opposite: to LOSE a few pounds, often with EXACTLY the same life and death fervor I've felt with regard to the cancerous tissue which has done such a swell job of digesting my spine that it actually BROKE... from nothing more than a sneeze or some other incidental stress. A compression fracture, so damaging that it would be unwise for me to attempt to lift the amount of weight I've now lost.

Put that all together -- the fervent ladies wish to lose as I have lost, then to fracture what I have broken, and you must admit there IS a certain element of humor... that struck me as the physician delivered the good news, and I began to laugh. And still haven't stopped. Not completely. But it certainly scared the hell out of the doctor.

"Time for you to put ON a few pounds, Chief."

"Aye-aye, sir!"

And I began to laugh. Because it struck me that, whatever else this cancer has done, it has given me what every woman longs for, as if it were a topic of polite conversation, suitable for those awkward moments when strangers are forced to spend a whisp of time together and a polite smile simply isn't enough, as in the elevator between 1 and 12, or the check-out line at the local supermarket. First, the friendly smile, then the casual: "I've got what you want," perhaps with another smile, depending on the lady's physique. Then back to listening to the elevator music or casually examining the contents of her shopping cart, my eye peeled for ice cream and Danish.

It gives you a nice boost, knowing you have what they want. Makes you want to flex your stick-like arms or show your turkey's neck to best advantage. Yup. Things are definitely looking up. Which is why I'm still laughing now & then.

-Bob Hoover

The Wire Tracker

Happy New Year to you all.

One of the more troublesome aspects of aviation electrical work is the fact our wires are usually NOT color-coded. That means you can have a bundle of twenty wires and before you can do any useful work you will need to figure out which one of the twenty at the equipment rack is the frayed one you've spotted behind the instrument panel.

How to do it? The good ol' fashioned way, which I described in an article some time ago, is to use a continuity tester. That is, a hunka wire long enough to run from here to there, a couple of flashlight batteries, and a flashlight bulb. You know you've found the correct lead when the bulb lights up. I even described a do-it- yourself tester based on an old-style Navy flashlight.

Alas, while 3 volts ain't all that much, you could be connecting those 'unimportant' three volts to a meter-circuit that blows it's top at two volts.

Whatcha REALLY want is a cable tracker.t

A cable tracker is a little oscillator that puts a warbling TONE on the wire under test, which you can then hear by waving a matching receiver at the other end of the wire.

Harbor Freight's gottem. Item #94181 about $20 US, probably less if you can find a Sale. (But Santa brought me this one :-)


Friday, December 26, 2008

Sunday, December 14, 2008

It's for Measuring! Honest!

As I said, you'll find a packet of cigarette papers in the tool box of most machinists.

(The blue-green Crayolas are used when flatting one surface against another. There's also some Crayola-brand CHALK in there for the same purpose. The Crayola items were purchased from American Science & Surplus Co.)

Thursday, December 4, 2008

Propeller 01 The Blank & Other Preparations

A good propeller begins with a good blank. The one shown here is not especially good. It lacks sufficient squeeze-out at the glue line. But it's good enough to serve as a training aid.

The blank shown here is made of pine weighing about 32 pounds per cubic foot. Which is pretty heavy for pine. The blank is a full six feet long, four inches more than required. Reducing the blank to sixty-eight inches will of course reduce its weight, as will carving the blank to the usual propeller shape. As shown the blank weighs twenty-two and a half pounds.

I've taken the trouble to mention the weight -- and the fact it will weigh less as the work progresses -- because I can't lift it, thanks to the cancer (mentioned in earlier posts). And since I can't lift it you may see me doing some rather silly things with the blank. That doesn't mean you should do the same :-)


The blank began as four pieces of shelving. To make-up the required three-inch thickness I had to stack the four pieces atop one another. Since this blank is specifically for training you may elect to use a different number of laminations, so long as you adhere to the basic rule: More laminations is better than fewer laminations.

In the same vein, I've used pine. You may elect to use a different specie of wood such as hemlock, cedar or what-have-you. But I think it would be wise to stick with softwoods, at least for this particular prop. 'Real' props are often carved from hardwoods but as you are about to see, a good deal of what you must learn has nothing to do with the type of wood you are using; in theory you could learn with a styrofoam blank.

I've used Weldwood 'Plastic Resin' glue on this practice blank and intend to use it on the real blank as well. 'Real' propellers generally use Resorcinol but it has become difficult to find. Some prop-makers are using epoxy and I've even heard of urethane being used, but the choice of adhesive is really up to you, since all commonly-available adhesives are stronger than the wood you'll be using.

In any case, given the amount of adhesive you'll be using, it's cost is insignificant compared to the cost of the airplane as a whole. Which is one of the reasons you want a good squeeze-out. A good, sloppy squeeze-out is the best insurance against a glue-starved lamination. If you'll examine the photos you will see that I did not get a good squeeze-out with this blank, which is why it would normally be rejected.

Saturday, November 29, 2008

Valve Job - Replacing Guides

The cast aluminum heads on a Volkswagen engine are fitted with four valve guides made of phosphor-bronze. The stems of your valves are installed in the guides. As the valves open and close, the small amount of clearance between the valve stem and the valve guide provides a direct path to the atmosphere. This isn't an especially good idea, so the valve guide is usually fitted with a seal. In the HVX mods I discuss the seal and show how to install them.

As the valves open and close they cause the valve guides to wear. The more they wear, the bigger the gap to the atmosphere and the more the valve will fail to run true. Due to the high temperatures present around the exhaust valve, the problem of a worn valve guide is more evident with your exhaust valves.

We periodically check the valve guides for wear. When the wear approaches the allowable limit, we replace the valve guide(s). The guides for the exhaust valves typically wears about three times faster than the guides for the intake valves. That means we will replace the exhaust valves about three times before we have to replace the guides for the intake valves. The exception to this rule is when you use the shorter valve guides from a water-cooled VW engine for your intake valves. (This modification is done to improve the in-flow at high rpm and does not apply to flying Volkswagen engines.)

To replace the valve guides we use a core drill, a suitable punch or drift, and simply drive them out. To install the new guides we heat the heads to 450 degrees on the Fahrenheit scale, chill the guides in dry ice or propane, and simply drive the new guide into the head. The first picture shows the step-drill and piloted driver used to replace (and install) VW valve guides. The picture on the right shows the stepped core-drill used to drill-out the valve guide before it is driven out of the head. When the valve guide is opened up in this manner it loses most of its grip on the head and can be easily driven out with a suitable punch or drift. The core drill is home-made. It starts out as a 7/16" drill bit. A half-inch (0.500") of the tip is ground down to a diameter of 0.3125"

The picture on the right shows the stepped drift used to drive the valve guide out of the head after it has been opened up by the core drill. The tip of the drift is turned to 0.308" for a distance of 1.125". The shank of the drift is 0.450" for a distance of 3.0". The drift started out as a standard 6" pneumatic drift but any bar of 1/2" steel can be made to serve.

-Robert S. Hoover
-30 Nov 2008

Saturday, November 8, 2008

How to Fix a Broken Back

Sorry, no pictures.

When Multiple Myeloma attacks the bones of your skeleton it does so one cell at a time. The resulting structure closely resembles a honeycomb, for want of a better comparison. When enough of the bone cells have been attacked the bone will no longer be able to bear its accustomed load.

When that happens, the bone BREAKS.

A sneeze can shatter your ribs. Bending down to tie your shoe can break your arm.

LIFTING A VW ENGINE can shatter your spine.

A Volkswagen engine weighs about 185 lbs. I am accustomed to picking them up and moving them around the shop with no problem. After I was diagnosed with MM I couldn't even pick ME up... and couldn't walk around my shop... unless I was braced with two canes.

I had crushed the third lumbar vertebrae in my spine. (Where's that? Put on a pair of skivvies, the waist band will fall right across the 3rd lumbar vertebrae.)

Being thicker, the top & bottom of the vertebrae was okay but the column between them was honeycombed and my normal activities -- probably lifting something -- crushed the vertebrae. Oddly enough, except for the initial fracture, this was not especially painful since it did not involve the spinal cord. So long as I assumed a posture that had me leaning forward, I was free of pain... until I had to bend or turn, in which case the pain could be so bad that there's simply no way to describe it. In time, this forward-leaning posture would have become my NORMAL posture, and the resultant pain would make my life a living hell.

To correct this abnormal posture I had to lay on my stomach and allow my spine to be stretched out to its original, pre-fracture dimension. This was quite painful but the pain was overcome with drugs.

The table on which I laid slide back & forth on a rail. There was an X-ray machine situated above the table and a fluorescent screen below the table, allowing the radiologist to 'see' my spine. The area above the fracture had been numbed with local anesthetics and I had been given additional pain-killers and tranquilizers.

The radiologist then inserted a large diameter needle (ie, 11mm or about 7/16") into the vertebra's crushed space, into which he pumped a fast-curing glue that served to straighten my spine and return it to is original dimension, or nearly so.

I was sent home after the procedure, higher than a kite from the pain-killers but literally feeling no pain. That was on Thursday the 30th of October. Today is the 8th of November and I'm feeling quite well.

The procedure is called 'vetebroplasty.' The procedure was developed in France in 1984 and is familiar to a number of Navy subscribers on this Newsgroup who have been using it to repair odds & ends of uncle Sam's sea-going machinery since the late 1970's, substituting JB WELD and a grease gun, instead of the more expensive medical equipment.

So... howz it working? It's a bit too soon to say for sure, but it seems to be a success, although I have to be careful whenever my wife is around, letting out a suitable moan or sigh and putting a hand to my back whenever she draws near. 'Cause if she thinks I'm getting better, she's got a list of 'honey-do's' as long as my arm... Ooops! Here she comes. I'll have to slip into Moaning Mode.

-Robert S. Hoover