It's a Jungle Out There

I'm packing my bag again for another overseas adventure. Chances are it'll be 1-2 weeks, which is barely enough time to get over the jetlag. This one is short compared to most trips I've made overseas and better yet, I'm going to a place where people speak my language. Admittedly the weather will likely be pretty cold and damp, but I doubt it'll be much more troublesome than Chicago this time of year.

I've mentioned that I spent plenty of time in Asia recently and having done so does help me to appreciate the value of working in a place where an industrial base is well established and a more or less capitalist economy is considered normal.

I spent considerable portions of last year and the year before in Vietnam. I forget the exact amount of time, but I know it was long enough to rack up 4 visas in my passport, become a familiar face to the entire lobby staff at the hotel, get invited to a local wedding, and navigate through much of Saigon without a map. I even had a chance to take in the Liberation day festivities while I was there. (Congratulations. Uhm, how's that whole, liberation thing working out for you?)

I stayed at a pretty nice hotel on the waterfront where you could see the fireworks display quite well. I'm glad too because I would not have wanted to be in the crowd on the street.

Of course I didn't actually work in Saigon, I actually travelled out to one of the nearby provinces every day where I was trying to piece together some back engineered surplus equipment for a new factory. It wasn't that far away, but it seldom took less than an hour to make the trip. The traffic and the roads made me glad I wasn't the one driving (the rental car came with a driver) because I'm certain somebody would have been hurt.

As you start off in Saigon, the roads are pretty good. The main thoroughfares are several lanes wide, well paved, only flood during heavy rain, and they have functioning traffic lights. I soon found out the traffic lights were mostly for show. Right of way seems to depend on the size of the vehicle, the volume of the horn, and whether or not you have a passenger hanging out the window waving people out of the way. Mopeds could usually weave in and around other traffic, but if you were in a car or small bus you had to go with the flow, and sometimes that meant you were going so slow that a one legged boy on a bicycle could pass you. (One time members of our team were able to get out for a smoke and a beer without fear of losing sight of our bus!)

Once you got out of Saigon the road conditions went downhill. I was working in a developing industrial region so the pavement had yet to catch up with the traffic. That wasn't really a problem on dry days but when it rained the unpaved surfaces combined with the lack of proper drainage meant that you would end up with enough potholes and washouts to slow traffic to a crawl. It didn't really help that most of the vehicles weren't particularly roadworthy.

Improvised taillights were probably the least of the hazards on the road. Overloaded trucks with poorly secured loads were the norm. I recall being in one traffic jam which was caused by a truck loaded with rebar stopped in the middle of the road. When we finally got to the head of the jam you could see that the rearmost axle had let go and the wheels were splayed outward in resigned acceptance of gravity's superior strength. I think the most accidents and traffic jams must have been caused by flat or blow tires. I'm pretty sure everyone there was operating on a 'run to failure' maintenance system because mopeds, cars, and trucks all had their share of bald tires. One case in particular was parked at the loading dock one day when I pointed it out to a coworker. The tire had obviously been retreaded at least once, and the replaced tread was coming off in such big chunks that you could no longer consider the tire to be round. My coworker commented on it, poking at the bare patches with his finger. The rest of us moved away and asked him not to tempt fate by poking the tire again.

Once we finally made it to work things weren't always so bad. I was working in a new factory, which meant it was pretty clean compared to what have seen elsewhere and we actually had an office and workshop area that was air conditioned, so you could always get away from the factory floor and cool down a bit if you needed to. We did have a few problems like flooding (or even rain) in the production area, but it's not like it rains every day in Vietnam, and walking around the puddles to check for wires is good exercise.

Of course being a new factory meant that there were a few things missing like workbenches, vises, calipers, air hoses, safety glasses, polishing compound, polishing wheels, light fixtures, electric cords with plugs, pipe fittings, bolts, micrometers, electrical tape, duct tape, solder, spare parts, cabinets, height gauges, flashlights, hand presses, taps & dies, and wrenches to name a few. The tricky bit was that when you needed something, or needed to have something repaired/modified, you couldn't just run down the road to Grainger or the local machine shop. You needed a guide who knew all of the local shops and businesses or else you were sunk.

You see, most of what is sold here comes through small shops, and while I like seeing local businesses make money, you really have to know your way around to find anything. To put it in perspective, suppose you were doing home repairs. Instead of going to the home depot and picking up everything at once, you would stop at a place like this for plumbing fixtures. Then you would look for a shed with a bunch of poles leaning against it to get your lumber, a shop with big spools of wire for your electrical supplies, and then maybe another shop after that to buy your hardware.

Plenty of times when I asked for a piece of equipment the answer was, "Saigon" meaning the nearest place to get it was in or around the city. That meant sending someone back to town. If they had to take a bus, it was usually a 4 hour round trip, but if you were lucky, you could send someone on a moped and cut the time in half.

Mopeds are the dominant mode of transportation for people and any other less than truckload shipment you need to make in Vietnam. You could break up the monotony of a long drive a little by looking for crazy things being carried on the backs of mopeds. There were usually two approaches to this. For bulk items people would hang baskets from the sides of their bike, stack the rear seat with boxes and then have the driver carry another basket or box in his lap.

It's blurry, but you get the idea. The other approach was the buddy system and this was usually for single or oddly shaped items like bookshelves, lamps, or plate glass windows. The driver would watch the road and the buddy would hold the package in between them. One time I noticed a moped with an oddly shaped cargo and I managed to get out my camera in time to capture it.

It was hard to see clearly at first.

It must be some kind of pipe, but how is he holding on to it.

Ah, he's wearing his cargo. Now I will refrain from making any flatulence jokes here, but if you are so inclined you may wish to make up your own that include the terms 'alternative fuel' and 'afterburner'

There were more colorful moped cargoes as well.
That reminds me, is Valentine's day coming up?

Ah well, I've never been big on buying flowers, why start now.

I have to say, the people I met in Vietnam were generally quite nice. The language barrier made things a bit difficult, but I was never treated with any hostility.

In fact I was sometimes surprised the number of willing workers around. Sure we played the little games where the mechanics tried to find excuses to go home early, but for the most part the mechanics and floor level Supervisors seemed genuinely interested in what we were doing and responded positively to both instruction and direction.

Where things got a bit tricky was dealing with management structures. I won't speak ill of anyone I worked with as we all managed to get the job done in the end, but you could certainly tell that when some subjects came up there was a resistance to make critical decisions or say potentially unpopular things. That's not really a surprise. Communist mindset is still quite strong in Vietnam and even though it's moving into a market economy. As a general cultural observation, making a decision means you're vulnerable to punishment when it goes wrong, and you'll get more work if it goes right. It's not surprising that few people will stick their heads above the parapet. Maybe that will change in the future, but I doubt it will change quickly.

Billboards like this are pretty common. The themes vary from heroic figures to idealistic looking villages full of healthy people working and 'doing their part.' I'm not really so interested in the translation of this billboard as I am the opinions of the people who go by it every day and the people living in the hovels just 100 yards down the road. I'm guessing not everyone sees eye to eye with the department of cultural affairs.

All in all, it wasn't a bad time. I suppose if I weren't trying to set up a factory in the jungle it would be a decent place to visit. Still, I think I enjoy spending my time in places with better motorways, fewer mopeds, safe drinking water, and fish that doesn't taste like the Mekong delta.

Until next time, look out for those bicycles and Ox carts!

Dress like an engineer

Apparently Kurt has taken me to task over not posting so I had best address the issue by putting up something new to look at.  I'll start with something which came to mind not long ago as I was reorganizing my closet.

I think more people need to dress like an engineer. 

Now I know engineers don't necessarily have a great reputation for being well dressed, in fact I'm certain that at least some of us have selected clothing based purely upon the weather report and a basic evaluation of the thermal properties of the clothing. (Forecast says wind today, I had best break out the forced air convection formulas.)

Still, there are many career minded engineers out there and many of them realize there is truth in the old saying  "Clothes make the man.  Naked people have little or no influence on society." (Mark Twain)

 Eventually this concern over the quality of wardrobe will cause one's mind to turn to ironing.  In fact with our wide array of off the rack clothes and automatic washers and dryers, ironing is the most time consuming part of dressing oneself. 

So what is the most efficient way to get your clothes pressed and wrinkle free?  Personally, I favor the Ironrite.  This device was initially dubbed the mangle ironer, referencing the then common clothes drying device better known as the wringer.

Eventually someone with a little marketing experience stepped in and provided a name that wasn't associated with unintended disfigurement and the Ironrite was born.  These are by far superior to other methods of ironing because they don't require you to stand over an ironing board and because the danger of entanglement adds a bit of an adrenalin rush to an otherwise dull chore.

Of course most of us don't have access to these machines due to space limitations or the fact that a new machine of this size and quality would cost substantially more than today’s consumers would pay for any device without an apple badge, a touch screen, and a set of white earbuds.

That pretty much leaves you with the ironing board and handheld steam iron.  While this approach is time consuming one can find some solace in the fact that steam irons are much better than the flatirons of years past.  The biggest difference of course is the addition of a steam system. 

Rather than rely purely upon direct conductive heat transfer, steam irons speed the pressing process by injecting  steam directly into the fabric, simultaneously heating the fabric from within and utilizing the heat of vaporization to transfer more energy than would be possible by conduction alone.  Of course this technology is still somewhat lacking in that there are currently no superheated steam or even pressurized boiler models availible to the average consumer.  For this reason I recommend only ironing on days with very high barometric pressure as your steam can reach higher temperatures.

Consult your steam tables for further information.

Individuals located at higher altitudes are at a disadvantage here.  Placing ironing boards at sea level (or just high enough above sea level to avoid electrocution) is preferable.  Conditions in death valley are probably best for the utilization of a steam iron, but I suspect the drawbacks of going there to iron would outweigh the benefits.

As to how you should go about ironing your shirts, well there's a very simple system I use to iron as efficiently as possible.  Just repeat after me: Collar, Sleeves, Front, Back. 

I always start with the collar.  Why? because a nice crisp collar is the most noticeable feature of a shirt and always conveys a good impression.  Also it's the only part of the shirt which is consistently visible regardless of the other garments you are wearing, and if you're trying to be efficient, why would you bother ironing the parts of the shirt that don't show?!



Take your shirts out of the laundry and press the collar first, then hang them up in the closet until you know what you're going to wear with them.  If it's the summer and you're dressing light, a nice vest might be in order, in which case you only need to iron the sleeves.  This saves the time ironing the other parts of the shirt.  Taking a few extra seconds to put a nice crisp crease along the top of the arm will make your shirt look nice and sharp and will completely avoid any suspicion that the remainder of the shirt is still sporting prune like wrinkles.

For more formal occasions when a jacket is required you must iron the front of the shirt, that is unless you decide to wear a three piece suit in which case having a well pressed collar is sufficient so long as you don't remove the jacket.  

Now the back of your shirt...well if you spend a lot of time sitting down or you are very conscientious about keeping your back to the wall, I say don't bother ironing what nobody will see.

So to recap, if you don't have a mangle iron be sure to use a handheld steam iron.  Only iron when the barometric pressure is high.  Always iron your collar first.  Only iron the other parts of your shirt if they will be seen.

If all else fails, just wear a turtleneck, sweater, and wrinkle free khakis. 

Don't miss the next installment of engineering fashion when I teach you how to accessorize like a true technical professional.

Another year comes and goes

Holidays with a twist

It looks like I'll be taking an unscheduled break.

Have a Merry Christmas everyone, I'll see you next year!

Safety First - Teamwork!

Harper Special

I just received next year's farm bureau calendar. I like taking these to the office because while everybody else has pictures of cars they can't afford, landscapes they'll probably never see in person, or slightly too adorable kittens, I am the only person there with a tractor calendar. I flipped through it once to look at the different pictures and Miss December the December tractor caught my eye. It's a Sears Economy tractor in bright red shiny paint. Farm Collector did an article on these back in 2009 which gives a nice little overview, but the short version is that it's a tractor frame with mostly automotive parts for the mechanical workings. Farmers could either buy the complete tractor, with it's rebuilt Model A motor, or they could buy a kit and furnish their own model A engine and complete the assembly themselves. It's a neat concept for an inexpensive tractor.

Reading about the Economy tractor made me think about a tractor I saw at Old Threshers this year which was dubbed the "Harper Special." This little mechanical marvel was parked in the truck section with a little sign briefly explaining it's history. Apparently it was built in 1944 by xx Harper who put it together from junkyard scraps and some oak beams back in 1944. The date of construction is actually quite significant. During the war years many things were hard to come by and tractors were no exception. For several years the lend lease program had been sending tractors overseas to support allied farmers so they could keep crop production high enough to feed their armed forces. Then as the US entered the war many factories were re-tooled to produce hardware for tanks, jeeps, artillery and all manner of other military equipment.

It was in the midst of this that Mr. Harper apparently went to the junkyard and gathered together his own kit consisting of a model T engine, two transmissions (one a model T one a 4 speed stick) a rear axle from a truck, A set of wheels (which look suspiciously like something you might find on a manure spreader) and other bits and pieces of equipment.


The result actually has some very clever features. First off, the oak frame seems to have eliminated the need for any significant amount of welding, which probably simplified construction and avoided the need to beg a ration board for steel beams. Model Ts had been around for over 3 decades by this point. There were plenty of them in boneyards to be picked over but they were simple enough to be serviceable and there were enough old Ts still out there that parts were plentiful. The model T engine has an add-on water pump to provide better cooling than the typical buoyancy based circulation. The engine has also been equipped with a governor which is mounted next to the water pump.



Seen here, the governor is connected to the water pump by wooden pulleys. The flyball mechanism works the linkage which actuates the throttle on the carburetor on the opposite side of the engine. The whole thing is connected by linkage back to a lever by the operator.


Also interesting is the use of a dual transmission setup. The model T transmission is really a very simple forerunner of today's automatic gearboxes in that it uses a planetary gear set and bands to provide the forward and reverse gears. The clutch is integrated into transmission and occasional adjustment of the band would keep it in satisfactory condition. By leaving the model T transmission and engine paired together Harper was able to simply use the low gear pedal to engage or disengage the drivetrain. The two forward gear ratios on this transmission also meant that you could drive the tractor in both high or low range. The 4 speed transmission (presumably 3 forward 1 reverse) inline with the first gave the operator a decent selection of gear ratios to work with. Of course it was necessary to mount extensions on the model T pedals so the operator could move them, and the reverse pedal was removed, probably in order to keep someone from putting both transmissions in reverse at the same time and going forward by mistake.

Mr. Harper even planned well enough to add in a PTO pulley by mounting a gearbox (or at least a set of bevel gears) in between the two transmissions.




I doubt I would want to pull very much with this tractor, but I would bet that with the proper hitch mount it could pull a two bottom plow like it's Sears counterpart just so long as the ground was dry enough for the wheels to get decent traction.

Isn't it amazing what can be accomplished with limited materials and a little ingenuity!

It's not just a profession,

It's a way of life. Once in a while I catch myself doing something and think, "I probably couldn't be anything other than an engineer." The latest incident came when I decided it was time to organize my closet. I took some measurments, started thinking about options and before I knew it I had it planned out in AutoCAD



Yep, planned complete with projected views. It was overkill but it did make me stop and think for a moment.



Engineers in my generation have little to no hand drafting experience. In fact by the time I was in school 2D CAD systems were passed over in favor of 3D modeling, at least in the world of mechanical engineering.



These are very effective tools that give us options nobody would have imagined just 50 years ago including the ability to generate ridiculously complex geometry that can be taken directly to CNC equipment.



The only problem I have with this is that when a computer program can do the heavy work for you it becomes easy to generate designs without having a thorough understanding of the geometry involved. Maybe I just worry too much about these things, but I still think there's something nice about being able to conjur projected views from just a concept and a few construction lines.

Change of season

Eleventh Hour of the Eleventh Day of the Eleventh Month

Please take a moment today to reflect on what our veterans have given us, and if you know a veteran, stop and say 'thank you.'

Explosion Motors (In Broad Strokes)

Last time I opened these books I shared some pages on basic 4 stroke engines. This week I’d like show you the section on 2 stroke engines.



Perhaps the biggest advantage of two stroke engines is the simplicity of the design. By using ports in the cylinder wall it is possible to build an engine with one valve or even none at all. The other, perhaps more obvious, advantage is that unlike the 4 stroke Otto cycle design you get a power stroke every revolution, so power tends to be quite good compared to heavy and more complex engines. This is however one of the great weaknesses of this engine types as well, because by condensing the intake, compression, power, and exhaust into half the number of strokes, you end up shortening the power and compression as well as overlapping the intake and exhaust. These changes really cut into your efficiency as high compression and a long power stroke are needed to thoroughly burn fuel. The overlapping of the exhaust and intake also cost some efficiency by allowing fuel to escape through the exhaust port. Add to that the constant flow of engine lubricant through the crankcase to the cylinder and you’ll always have plenty of unburnt oil products blowing out the tailpipe.



Considering all that, it isn’t surprising that two strokes aren’t common in the automotive world. Where they tend to excel is in small handheld tools (blowers, weed whackers, chainsaws, etc) where weight and power are the primary concerns.
The fact that the two stroke appeared so prominently in this text is testament to the fact that in the 1920s people were still very unclear on where the automotive industry was headed. Of course, the American Technical Society was not shy about including extra information in this text. In fact they actually put in a section on aircraft engines.

Brigid mentioned the Antoinette engine in the comments so I did a little looking. I had no success in my old texts, but I did come across a real aerial oddity while I was looking. So, find your white scarf and we’ll take off on a tangent.



This is a Frederickson 70 hp rotary engine. Actually, I should say that again. This is a ROTARY engine, meaning the crankshaft is fixed and the cylinders rotate, unlike a radial engine where the crankshaft turns instead. Having the engine rotate may seem a bit odd, but during the early years of aircraft development this configuration did hold some advantages compared with some of the other options available. This approach could produce a reasonably lightweight design without the need for flywheels or cooling systems. Of course I wouldn’t want to ignore the fact that you were mounting a rather large spinning mass on the front of a light weight machine that has only its wings to provide opposing torque. That’s not necessarily a problem if you only need to turn in one direction, but it’s certainly not conducive to straight and level flight.



Still, rotary engines like the Gnome Monosoupape (single valve) kept much of the early air power aloft.

The Frederickson design is apparently an oddity even for a period rife with failed experimental designs. It’s a two stroke five cylinder rotary design. There were only a handful of two stroke rotary designs, and from what I understand the commercial success of these was quite limited. The lack of valves and their accompanying pushers, cams and reduction gears does hold considerable appeal when constructing an aircraft engine, but there is one very noticeable drawback. Two strokes depend upon the compression of the fuel air mix in the crankcase to properly charge the cylinder during intake. That doesn’t work very well when you share a crankcase with four other cylinders at different points in their stroke. To get around this, I understand some designs like the Murray Willat Lamplough 6 cyl 2 cycle Lamplough used a blower system to maintain positive pressure on the crankcase.

Frederickson took a fairly simple approach and used a sleeve attached to the connecting rod by a swivel.



The lateral motion of the rod (relative to the cylinder) would move this sleeve back and forth, opening a port to admit the fuel air mix when the piston on the compression stroke and seals it on the power stroke thereby compressing the mixture prior to the intake phase. It’s actually quite a neat solution even if it might not be the best for maintenance.



By the time this design was developed, rotary engines were starting to fall behind their radial and inline counterparts. Rapidly improving design and manufacture meant that engines were becoming more reliable and able to rev to higher speeds, while rotary engines encountered dramatically greater wind resistance and higher structural stresses as the rev speeds went up.



Engines like the V8 Hispano Suiza became increasingly popular as did various flavors of radial engines. While the Gnome Monosoupape engine (probably the most common rotary design during the war years) topped out near 150hp, designs like the Hispano Suiza 8 cylinder entered production at 150 horsepower and quickly evolved to models producing well over 200 horses. These provided power for planes like the SE5a and various generations of Spad designs which had a significant impact on the balance of air power in 1917 and 1918.


I’ll start digging for more good tech manual material and see if I can come up with anything interesting for next time.