Sunday, December 17, 2006

VW - Clutch Alignment Tool


Any device that maintains the concentric alignment between the clutch disk and the pilot bearing can be made to serve.

The standard VW tool was made of hardwood. If you have a wood lathe, making such a tool is a snap. Little end matches the pilot bearing, shank matches the hole in the clutch disk (you can ignore the splines, focus on the hole) and anything left over serves as a handle.

Put your mind to it, you'll see that you don't even need the lathe; anything that can hold a hardwood dowel while spinning the thing can be made to work, and a rasp does just fine as a cutter.

(Ed.Note: I made the alignment tool in the photo above for my '73 Datsun [which I still own].)


Have you got a set of deep sockets? See if you can find one that is a reasonable fit in the pilot bearing. Now see how well the big end of the socket fits the center of the clutch disk. I have a set of metric sized, 3/8" drive deep-sockets made by S-K. The 10mm socket makes a perfect alignment tool for the VW clutch disk.

Lots of folks sell cheap plastic alignment tools. Before using anything made of plastic for this purpose you should check the alignment of the tool itself. In a lot of cases the little end is at a distinct angle to the clutch-part, guaranteeing you'll never get the engine to slide on to the main-shaft.

You'll also see a lot of stuff about how an old main-shaft makes the perfect alignment tool. Which it does. But only if you keep that sucker absolutely, positively horizontal when torquing up the pressure plate. That's because an old mainshaft is also a worn-out mainshaft, especially with regard to its fit in pilot bearing and the splines for the clutch disk. Old mainshaft generally means a sloppy fit, which leaves a lot of the alignment up to you.

This is one of those problems that can have you bleeding from the eyes because all of the Instant Experts tell you what a great idea it is to use an old main-shaft... but none of them take the trouble to mention what happens if the shaft is allowed to droop, or when it's worn so badly that it fails to keep the clutch disk concentric to the pilot bearing.

--------------------------------------

Funny/Sad Story: Couple of kids, first bug; taking advantage of their first engine removal (bad clutch) to add tons of those kewl improvements you can just bolt on, makes a bug go a thousand miles an hour, etc.

Couldn't get the engine back in. Spent something like three days really trashing that poor bug before the mother of one of the kids got in touch with my wife to see if I could drop by, maybe give them a hand.

When I showed up, the clutch disk was visibly misaligned. When I pointed out the misalignment they were defensive, didn't need any help, etc. They called said the need for an alignment tool was 'bullshit'. According to them, the clutch disk would align automatically as the engine was installed.

So I left them to it. You can lead a horse to water but from that point on, the rest of the job is up to the horse.

-Bob Hoover

(Ed.Note: I posted the above several years ago, leaving out a lot of details such as the fact the family were renters and that major car repairs were a violation of their rental agreement. I eventually got the kid back on the road but only after the family had been threatened with eviction. But once the engine was installed it ran like shit, thanks to all those improvements the kid had installed at the instigation of his equally ignorant buddy. As with most of these tales, it didn't have a happy ending and another bug ended up in the crusher.)

Saturday, December 16, 2006

VW - Head Baffles


With more than 22,000,000 air cooled engine’s-worth of experience you can bet your bippie Volkswagen knew what it was doing with regard to the cooling system. Everything you see on the engine is there for a purpose and the only thing you will gain by leaving something off is a reduction in the engine’s useful life.

One of the most critical parts on VW heads is the small air-dam located on the underside of the head between the combustion chambers. Without this air-dam in place most of the cooling air reaching the heads is lost. With the air-dam in place, the gush of cooling air is obstructed and directed to either side, bathing the underside of the combustion chambers. When the cooling air is slowed down in this manner two things happen. The air picks up more heat since it is in contact with the heads for a longer period of time. The second – and more important thing – is that the pressure of the cooling air above the heads will rise.

Didja get that? The cooling air pressure goes up with the air-dams in place.

It is that subtle increase in pressure that allows the cooling air to be forced toward the corners of the heads, out toward the exhaust valves – the hottest parts of the engine, where it is needed most.

All of the new heads I've seen in the last five years or so did not include the little air-dams on the underside between the chambers (ie, where the thermostat rod goes). They are also missing from most overhauled heads. As the Mechanic-in-Charge it is your job to ensure they are in place.

I make these out of .010" stainless steel shim-stock, secured with fine SS safety wire.

I cut the air-dam to fit with scissors (!) then drill a small hole near each corner. I drill one hole through the middle fin in the center of the area to be covered by the air-dam and thread two lengths of safety wire through the hole, then thread the wires through the four holes in the air-dam and work it down the wires until it rests flat. Then I simply cross the wires, twist them tight, snip off the ends and press the twists flat against the air-dam.

Yeah, I know – Mexican-built beetles don’t have them installed. Nor do they use a thermostat. But you’re comparing apples to oranges. The stock 1600 engine built for domestic (ie, Mexico) use is fitted with dished pistons giving it a compression ratio of only 6.6:1, allowing it to run on low octane Mexican gas. In that configuration it is DERATED to 45bhp. This engine uses multi-point FUEL INJECTION. Cooling is handled by the engine’s on-board COMPUTER which automatically reduces the injector on-time as the cylinder head temperature increases.
-----------------------------

You can improve the cooling ability of your heads by a considerable amount if you will abrade the fins with COARSE media. (I use #80 sand.) DON'T blast anything else on the heads but DO try to get down between the fins. Mask-off the chambers, all of the studs, the exhaust ports, inlet port & sealing surface, and the entire valve gallery, taking special care to insure the gasket rail remains mirror-smooth.

Abrading the fins increases their surface area; the more area, the more heat that can be transferred to the cooling air.

Note: Normally, abrasive media is NEVER used on non-ferrous materials; heads are usually cleaned with walnut shells. But this procedure is now commonly done by the manufacturers of aircraft engines as a means of improving the head's cooling ability.

-Bob Hoover

Friday, December 15, 2006

DeltaCAD - A Useful Tool


In December of 1995 I was standing in line at the check-out counter of the CompUSA store in Escondido, California. It was a few days before Christmas and the place was packed, the registers apparently manned by people who’d never seen one before. The lines inched along beside the ‘bargain’ tables; software from companies I’d never heard of, most of it junk. Trapped in the check-out line, we sifted through the debris of progress.

‘The World’s Easiest CAD Software!’ caught my eye. I was trying to learn CAD in order to transmit drawings via the internet. The program was called ‘DeltaCAD’ (version 1.0) and CompUSA had it marked-down to a fraction of its original price. Reading the box, it sounded less complex than the CAD program I was struggling to master and I bought a copy, thinking it might help me learn the hard stuff by starting with something easier.

Ten years later, I've tossed AutoCAD, TurboCAD and WhateverCAD in the trash. DeltaCAD has done everything I’ve asked of it in the way of drawings, from a full set of plans for a seven-room house to the tumbler-bridle of a flintlock rifle. It has proven invaluable in the shop, producing lay-outs with an accuracy of better than 0.001" from an inexpensive Hewlett-Packard printer. When fed to a laser printer, it has produced intricate circuit boards. Now in version 6.0, DeltaCAD has proven to be the smartest money I've ever spent for software.

As a drafting tool, there’s lots of stuff DeltaCAD can’t do, such as 3-D, G-code generation for CNC and so forth. But for forty dollars it handles at least 95% of the chores other folks do with CAD software costing ten times as much and usually produces a more compact file, allowing for the quick transmission of even the largest drawings. The software itself is equally compact, allowing it to run on older systems, such as the desk-tops many of us have relegated to the shop.







Mention 'CAD' and people tend to thing of machines but the term means 'Computer Aided Drafting' and that means every kind of drawing, such as the compass rose shown at the right.








If that compass were installed in an airplane there is a legal requirement that it be accompanied by a Compass Correction Card. The size of a business card, the friendly folks at the local FBO will sell you one for about five bucks because everyone knows all pilots are rich, right?












Most folks who build their own airplanes put their nation's flag on the tail. I used DeltaCAD for that particular chore.






DeltaCAD has also proven very handy around the shop, where I've used it to create copies of useful tables, such as bend allowances, drill sizes and so forth.


There's no secret to marksmanship. Some folks are better shots than others but the key to maintaining whatever skills you have is practice. Skeet is fun albeit a bit over-organized. Paper plates, poker chips and even blocks of wood make handy targets for instinctive shooting. But it all begins with punching holes in paper. Once a youngster has mastered the basic skills they can move on to whatever type of shooting they find most enjoyable. Or not.

The targets below are produced by a laser printer then glued to cardboard and installed in a pellet-catcher. All of the drawings shown here -- and several hundred others -- were made by me using DeltaCAD. The drawings may be of any size; the compass correction card is about 1.5" x 2" wheres the rib below was four feet long.

The software supporting this blog is oriented more toward the chat-room than the machine shop and does a poor job with technical illustrations. But the range of examples shown here should make it clear that CAD is an enormously useful tool, its application limited only by your imagination.

-Bob Hoover

Thursday, December 14, 2006

VW - Wet Sanding Woes




>My hands are so dry the skin is cracking. But, at least the car is almost ready for painting.

-------------------------------------

Dear Mel,

Aloe vera is perhaps the best kept secret of the Manual Arts and is standard stuff in the custom car world :-)

Aloe is a succulent, a fleshy plant similar to cacti but without the spines. Break off a spear about six inches long, crush it in your hands and smear the gooey green juice all over them. When it dries, you rinse it off with cold water.

The juice is a natural emollient with anti-bacterial properties.

It's very easy to grow, indoors in a pot or outside in a mild climate.



>Can you buy the seeds, or is it pulps? Not likely to find it in Norway....
---------------------------------------------------

Dear P.J.,

Ask around among friends with indoor plants. It grows readily from cuttings.

It is an attractive plant, safe around children and pets. It produces a stalk of red blossoms, so seeds should be available. I saw it in a hanging pot at the home of friends when I visited Denmark some years ago so I think you will find it locally, although not in the wild.

One method of 'rooting' the plant is to cover a container, such as a drinking glass, with paper secured with a rubber band, after filling the glass with water. Make a small X-shaped slit in the paper with a razor and insert the cutting so that it's cut edge is immersed in the water for about half an inch. The paper will support the upper part of the cutting, which should be from four to six inches long.

Place the glass on the ledge of a window or wherever it can get sufficient light, and leave it alone.

Depending on the temperature and amount of light, in one to two weeks the cutting will produce a growth of hair-roots. After the roots appear, transplant the cutting into a small pot containing a basic planting mix (ie, typically about half earth & moss). Keep the planting mix slightly damp until the cutting produces new sprouts, indicating it has established itself.

Once it is established you will find it to be surprisingly hardy, able to withstand long periods of drought. But it is fairly sensitive to freezing; the roots are frozen solid it will usually die but it can withstand a light frost without permanent harm.

Cuttings can also be 'rooted' directly, using sand as the media, although it will take longer to establish itself.

To which someone else opined:

>go to a feed store (or some odd specialty stores like some old fabric
>stores) and get "Udder Balm". It makes such a difference it is AMAZING. >(Take it from someone who has had cronic dry/cracked hands from working on >the car, woodworking, etc...)


-------------------------------------------------------

This sounds like 'Bag Balm.' (Little square green can?) Unless you're in a very cold climate -- and dealing with udders instead of your own hands -- I suggest you try the aloe first. If you've never used it, you'll probably be surprised at how well it works.

Working concrete in cold weather, and commercial fishing, Bag Balm (or similar) would be my first choice. But if you can get to where it's warm, and can dry your hands, the aloe will heal them up where Bag Balm just fills up the cracks. Up to you. They're you're hands :-)

-Bob Hoover

Wednesday, December 13, 2006

Steel and Knowing it All




Someone wrote:
>German vs. Japanese steel?...give us a break with this nationality stuff.......<
------------------------------------------

Okay. Here's your break :-)

About 1868 a Prussian military officer witnessed a Japanese samurai use his sword to cut through the barrel of a musket without damaging the sword. He was not able to buy a copy of the sword but he was allowed to view a sword-maker at work and to purchase several tons of the ore he used. Back in Germany the ore was reduced to iron and the iron converted to steel. It proved to have remarkable properties of strength, toughness and hardenability, which was eventually attributed to traces of molybdenum in the original ore.

--------------------------------------------------------

We now have the ability to identify the composition of almost anything down to a fineness of so many parts per million. At that level of precision you'd think nature would have no secrets left. But there are some compounds that are lethal to humans in concentrations as low as parts per billion... and a virus is even smaller than that, when compared to the mass of the human body. When we insist we know everything there is to know about steel, engineering or whatever, we're actually defining the existing limits of what we know. Which is another way of saying we've still got a lot to learn.

-------------------------------------------------------

Do you weld? It's a useful skill, easy to learn. But it will teach you at first hand that no matter what it says on the spec sheet, not all steels are the same. That's because most utility-grade steels -- 'angle-iron.' ERW tubing and so forth -- tests only for the basic composition of iron & carbon. In recycling an oil tanker or old aircraft carrier most of the steel will return to the marketplace as basic SAE 1020 mild steel, which most of it is. But a lot of it isn't. I have made excellent leaf-type springs for flintlock rifles from rebar that came from the re-cycled hull of a Russian ice-breaker. The same is true for those 'national' steels someone mentioned. More than three quarters of all the steel ever made in America used ore from the Mesabi and Vermilion ranges in Minnesota. Old railroad men say they can tell the difference between a Mesabi rail and a Birmingham rail by its ring. I can't but maybe they can. And for a reason. Trace amounts of certain elements often result in steel having advantageous properties even though the tests show it is just plain old fashioned garden variety mild steel. Strange but true.

---------------------------------------------

So what's the point?

Mebbe that we should give folks the benefit of the doubt, even when they say something that appears to be nonsense, such as one nation’s steel being superior to that from another country, or knowing someone who can walk on water. (Come to think of it... :-)

--------------------------------------------------------------

Then Dan wrote:

Interesting story. What would also be interesting is to the know the origins of the ore, since Japan is notorious for its lack of iron ore. They invaded several countries toward the end of the 19th Century and into the beginnings of the last century in search of iron ore deposits for their steel industry. One of those countries produces Hyundais if that is any help. Another is famous for its woks.


Well.... as a matter of fact, in 1868 none of those things had happened as yet. But I can appreciate the question, especially since Japan was making superior steel blades as early as 900 AD. The answer is quite simple. Look up ‘bog iron.’ This form of biologically concentrated iron was common in the marshes and streams on the three southern-most Japanese islands with some deposits large enough to support commercial mining operations (see the Gunma iron mine north of Tokyo) although not on a scale sufficient to support the level of industrialization desired by Emperor Meji.

-Bob Hoover

Tuesday, December 12, 2006

VW - How to Cook a VW Bus






I thought I'd seen/heard every way there was to set your bus on fire. Wrong.

A local fellow (near Vista, California) managed to do it by overhauling his carb.

After rebuilding the carb he fired it up to adjust the idle. Left the air cleaner off. He said it didn't want to start but finally did, running kinda funny, as if a plug wire had come loose. That's when he saw the smoke. Shut off the engine but the thing was burning pretty good by then.

No fire extinguisher of course. He had one but it was buried under a lot of stuff in the back of the bus and the bus was in the garage and he was on the opposite side and besides, there was a garden hose just beside the garage door.

If you drive an air cooled VW a fire extinguisher is some of the smartest money you can spend. If you drive a bus, you need two of the things, one located in the cockpit where the driver can grab it as they jump out, the other in the cargo bay.

He used the garden hose. Worked, but only because there wasn't a pool of gasoline
under the bus.

Hell of a mess. The rear portion of the air seal was fried, along with the fan belt and most of the wiring. But it wasn't quite as bad as it looked. Had to drop the engine so he could replace the air seal. I went over and helped him with the wiring.

The cause of the fire was a mystery. And he'd already figured out that it would be plain crazy to put the engine back in without knowing why it had caught fire.

The only clue I considered significant was that the gasoline had sprayed all over the top of the engine compartment. I thought the fuel hose had blown off or he'd left out a gasket. But the fuel line was in place. All of the gaskets on the carb were in place and the screws were tight. So maybe it was the fuel pump. Or perhaps he'd used one of the old gaskets by mistake. Old gaskets often break when you remove them, leaving a gap for the fuel to escape. The
overhaul kit was still on the bench along with the old gaskets. And two float valves, the old one he removed from the carb before soaking it in carb cleaner, and the new one he forgot to install. Mystery solved.

The float bowl is vented to the atmosphere. On the Solex the vent is a metal pipe about a quarter-inch in diameter that points into the open throat of the carb at an angle. With no float valve installed, once the fuel pump filled the bowl the vent acted as a nozzle, squirting gasoline out of the carb (no air cleaner), onto the ceiling of the engine compartment and from there, all over the engine compartment.

Distributor cap was still in place so the initial ignition point was probably the generator brushes, which create sparks during normal operation.

The Boot Camp of Reality is coming to grips with our own fallibility. Alas, it's a lesson most fail to learn. Once you accept the fact that errors are human and therefore normal, you make it a habit to write things down, to measure twice before cutting, to use lay-out boards when assembling an engine, to use check-off lists before take-off and so on. Not very kewl of course but totally professional.

Education is usually expensive. This lesson was a bargain. He's still got his bus. And his house.

-Bob Hoover

PS - I stole the pictures from the internet. The one at the top is from www.ratwell.com, the one above is from Australia

The Beekeeper's Tale


According to the dentist, Mr. A. C. Doyle, Sherlock Holmes retired to Sussex, where he kept bees.

This information was passed along to me by my grandfather when I was about six years old, as we prepared to rob one of the four hives which were a vital part of the family farm. I didn’t especially care for bees but I was sinfully fond of honey on hot buttered biscuits and my grandfather used my love for the one to overcome my fear of the other by weaving a tale of beekeepers past, such as Sherlock Holmes, of secret agents and Pickle, the Mayan King.

His name wasn’t really Pickle, it was Pae’kal, according to my grandfather who learned about him and the fact he’d been a beekeeper from his younger cousin Sylvia who was actually a boy named Sylvanus and the best American spy who ever lived although twenty years younger than my grandfather and product of one of them eastern schools. But a cousin all the same, through the Griswald side of the family and an honest to God spy for the American Navy back before the First World War when my grandfather was going through what he called his sea-going phase, which was how he acquired the faded blue tattoos on each of his hands, one of them a five pointed star, the other a crescent moon.

“All you needed was to know a little Quichi,” according to my grandfather, that being the language of the Mayas, to know the king’s name wasn’t Pacal, nor Pakel or even Pakal, which is what everyone else called him. “Sylvee knew Quichi top to bottom, front to back and all the dialects in between.”

My grandfather knew all that because he’d been first mate on a banana boat at the time, running between Seattle and Valparaiso, and Quichi, or key-chee as he called it, was just one of the languages he’d picked up in his travels. And he knew about the spying because he’d done his bit, carrying books back and forth between his cousin and the Naval Attache at Panama City, where grandfather’s ship was required to stop for coal. Then he made me stand to attention and solemnly swear I would never mention the spy business to another living soul.

And about there I realized the honey-filled supers had all been replaced with empty ones and we were trudging back toward the house, richer by forty pounds of honey in the comb and unstung.

Mention of spies and royal beekeepers overcome my fear of bees and I eventually became a fairly accomplished apiarist, taking up the hobby on a larger scale after I retired from the Navy, continuing until 1998 when Africanized bees reached San Diego county. African bees are just as useful as other bees but having evolved in Africa they’ve developed the tactic of attacking en mass whenever they feel their hive is threatened. It’s the only way they can drive off animals the size of elephants. Unfortunately, they use those same tactics against children, pets and beekeepers. Such bad manners made them unwelcome in our patio and I reluctantly gave my hives to a professional beekeeper. Indeed, such behavior makes them unwelcome anywhere within a mile of the house.

In the fall of 2006 Mel Gibson released a movie he’d made about the Maya and it caused me to recall my grandfather’s mention of Pickle the Mayan Beekeeper. Thanks to the internet it took only a few minutes to confirm that the Mayas had indeed practiced beekeeping on a significant scale using the stingless native American bees, and that one of their more notable leaders was a fellow named Pa kal, spelt in various ways. Even more amazing was to discover there really was an archeologist named Sylvanus Morley in Central America who had worked for Naval Intelligence!

Further confirmation of my grandfather’s tale came from learning Mr. Morley was about twenty years younger than grandpa and that his middle name was Griswald.

Which leaves only one question: To which part of Sussex did Sherlock Holmes retire? Being something of a bug about English history the question is really my grandfathers. Sussex was once a kingdom, according to him, divided into East and West Sussex when Jeeter was pup. He finally decided upon Rye as the only suitable location for the retirement of a consulting detective and put his reasons into a neatly written monograph in his Book of Private Thoughts, shared with no one over the age of twelve.

-Bob Hoover