Sunday, November 11, 2007

Pittance of time

This video has been around for a while, but if you haven't seen it before or if it's been a while, please take a few minutes to watch.

It's a really touching tribute to veterans!

Monday, September 10, 2007

News that isn't.

When you spend a weekend working out of town, it's really easy to end up in a hotel room at night watching the news channels and their ad nauseam coverage of news that really isn't news. In particular the newscasters were all enthralled with the latest Osama tape. I suppose that it's more news-worthy than the 6 straight hours of Paris Hilton reporting that I had to sit through in the Detroit airport, but I still find it amazing that there would be so much gawking and chattering about why the most wanted (or unwanted) man in the world would dye his beard.

It sure makes newspapers more appealing.

Do not fear when your enemies criticize you. Beware when they applaud.

(Vietnamese proverb, as quoted by Vo Dong Giang.)

Friday, August 31, 2007

Old Threshers

Old Threshers Reunion is this weekend. I've posted about it before, but there's really no substitute for going to Iowa to see it.

Thursday, August 23, 2007


This is my third week in a row of being on the road, but at least I'll be taking some vacation time soon. Check back in a few more days for some posts.

Wednesday, August 08, 2007

Quote of the unspecified temporal interval

The great liability of the engineer compared to men of other professions is that his works are out in the open where all can see them. His acts, step by step, are in hard substance. He cannot bury his mistakes in the grave like the doctors. He cannot argue them into thin air or blame the judge like the lawyers. He cannot, like the architects, cover his failures with trees and vines. He cannot, like the politicians, screen his sort-comings by blaming his opponents and hope the people will forget. The engineer simply cannot deny he did it. If his works do not work, he is damned.

- Herbert Hoover, Opening Quote of Chapter 5, Introduction to Aeronautics: A Design Perspective by Steven Brandt et Al.

This quote came up recently in a discussion with a coworker. It seems even more important than usual given last week's news from Minnesota.

Thursday, July 26, 2007

For pet owners servants

How to Give A Cat A Pill
  1. Pick cat up and cradle it in the crook of your left arm as if holding a baby. Position right forefinger and thumb on either side of cat's mouth and gently apply pressure to cheeks while holding pill in right hand. As cat opens mouth pop pill into mouth. Allow cat to close mouth and swallow.
  2. Retrieve pill from floor and cat from behind sofa. Cradle cat in left arm and repeat process.
  3. Retrieve cat from bedroom, and throw soggy pill away.
  4. Take new pill from foil wrap, cradle cat in left arm holding rear paws tightly with left hand. Force jaws open and push pill to back of mouth with right forefinger. Hold mouth shut for a count of ten.
  5. Retrieve pill from goldfish bowl and cat from top of wardrobe. Call spouse from yard.
  6. Kneel on floor with cat wedged firmly between knees, hold front and rear paws. Ignore low growls emitted by cat. Get spouse to hold head firmly with one hand while forcing wooden ruler into mouth. Drop pill down ruler and rub cat's throat vigorously.
  7. Retrieve cat from curtain rail, get another pill from foil wrap. Make note to buy new ruler and repair curtains. Carefully sweep shattered figurines and vases from hearth and set to one side for gluing later.
  8. Wrap cat in large towel and get spouse to lie on cat with head just visible from below armpit. Put pill in end of drinking straw, force mouth open with pencil and blow down drinking straw.
  9. Check label to make sure pill not harmful to humans, drink 1 beer to take taste away. Apply Band-Aid to spouse's forearm and remove blood from carpet with cold water and soap.
  10. Retrieve cat from neighbor's shed. Get another pill. Open another beer. Place cat in cupboard and close door onto neck to leave head showing. Force mouth open with dessert spoon. Flick pill down throat with rubber band.
  11. Fetch screwdriver from garage and put cupboard door back on hinges. Drink beer. Fetch bottle of scotch. Pour shot, drink. Apply cold compress to cheek and check records for date of last tetanus shot. Apply whiskey compress to cheek to disinfect. Toss back another shot. Throw tee-shirt away and fetch new one from bedroom.
  12. Call fire department to retrieve the friggin' cat from tree across the road. Apologize to neighbor who crashed into fence while swerving to avoid cat. Take last pill from foil-wrap.
  13. Tie the front paws to rear paws with twine and bind tightly to leg of dining room table, find heavy duty pruning gloves from shed. Push pill into mouth followed by large piece of steak. Be rough about it. Hold head vertically and pour 2 pints of water down throat to wash pill down.
  14. Consume remainder of Scotch. Get spouse to drive you to the emergency room, sit quietly while doctor stitches fingers and forearm and removes pill remnants from right eye. Call furniture shop on way home to order new table.
  15. Arrange for Humane Society to collect mutant cat from hell and call local pet shop to see if they have any hamsters.

How to Give a DOG a pill

  1. Wrap it in bacon.

Thursday, July 05, 2007

Little Chapel - Where?

I'm on vacation this week, so I drove down to southen Illinois to see the family for a little while. We decided to tour around the countryside one day and we ran across this sign.

I've seen little chapels/churches before. I know that when you see a sign for a little church you can usually expect something like this.

This is "The Little Brown Church" just north of Waterloo Iowa. It is a typical small country church.

But this is the Little Chapel Church of Southern Illinois

No, the little church is not behind that humongous building. That building really is The Little Chapel Church

After a closer look we determined that the building was about 400 feet long by 200 feet wide with 37 separate air conditioning units! There is also a day care center with a playground, a huge parking lot, and a bus barn.

I think the "Little Chapel Church" is a very nice name, but as a description it requires more than a little imagination!

Monday, July 02, 2007

Power to the Pulleys

In my old technology posts thus far I have talked about power sources, but i have yet to talk much about how this power is utilized. In the modern world where every little gadget, power tool, and machine seems to be driven by electricity, it's easy to forget that all of that power has to come from somewhere. Electric cords just blend into the background, and battery powered devices eliminate the cords entirely, but this is an incredible luxury compared to what was previously done to operate machines.

Look back at my post on the Aldie Mill in Virginia. You'll notice the power from the waterwheel is transferred directly to the millstones by way of large shafts and gears. This works well for one or two devices, but what if you want to transfer that power to multiple machines? When the mill was upgraded over the years, it began to use roller mills, similar to these. To completely process grains, you typically needed several units. In order to power them, the mill began to use line shafts.

Here, one of the waterwheels is connected, by way of a large pair of reduction gears to a pulley. This would, when operational, have a large belt connecting it to a much smaller pulley on another shaft. That shaft could then be extended to nearly the length of the building. Wherever power was needed for a roller mill, fan mill, or other device, a pulley was placed on the shaft. That pulley, and another belt, would transfer power to the machine below.

Of course if you can do this with water, you can do this with steam or gas engines as well. This is why most older engines either had a large pulley attached to the crankshaft or else had a wide flat flywheel that could be used to run a belt.

To make this a little easier to understand, let's look at a model.

This miniature machine shop is made up mostly of kits from PM Research who display and sell their wares at the Old Threshers Festival. Here, a model steam engine is connected to a line shaft, via a belt.

This shaft runs the length of the building, and is connected to other shafts and machines, all of which could be powered by the engine at the same time.

Of course, this has some potential complications. Very seldom will all of the machines in a shop need to run at the same speed, yet when they are all running at the same time, you can't just change the speed of the steam engine to suit one particular machine. This is why different sizes of pulleys are used. Two pulleys of different sizes act in much the same way that two gears of different sizes will act. A large pulley when connected to a smaller pulley, will cause the smaller pulley to spin at higher RPMs. By using this knowledge, you can have a line shaft that spins at a set speed throughout a facility, and yet have machines running at various different speeds.

To complicate matters further, some machines needed the ability to be adjusted to run at multiple speeds.

You may notice in this picture that some of the machines shown have a pair of multiple diameter, almost conical pulleys. These are connected with a thin belt that runs between one pair of pulley diameters at a time. Adjusting the belt to one set of diameters or another, changes the diameter ratio and therefore the RPM ratio of each of the pulleys. So each diameter on each pulley represents its own speed, almost like a modern selectable gearbox. (Incidentally, if you make the pulleys perfectly conical then you would be creating a continuously variable transmission.)

Sometimes it was necessary to stop a machine entirely. This created another problem because nobody wanted to shut down an entire factory just to work on a single machine. It became necessary to isolate machines from the line shaft. I'm sure there were several possible methods for this, but the simplest was simply to move the belt to an idler pulley. Either on the machine or on the line shaft, a free spinning pulley could be mounted so that when a machine needed to be stopped, the belt was simply moved from the main pulley to the idler pulley, where it could not transmit any power. Similarly, a belt might be allowed to go slack, so that there was not enough friction between the belt and the pulley to transmit any significant force. Both methods worked, even though they were far from perfect.

Still, systems like this were used in all manners of facilities from machine shops and factories, to grain or textile mills, and other manufacturing facilities. Over the years, they would be used with waterwheels, steam engines, gas engines, diesel engines, and eventually, they would even be adapted to run under power from large electric motors.

The line shaft system did have drawbacks. All of the moving parts created plenty of friction, so efficiency suffered. It also required considerable time and effort to make sure that all of the line shafts were well maintained and lubricated. Safety was one of the primary drawbacks of a line shaft operated facility. Even though machines could often be disconnected, it was rare to completely shut down a system, so people were often injured by working on moving equipment or trying to put belts back on pulleys after they had slipped off. Unguarded belts and pulleys can be particularly hazardous because of their ability to catch appendages or loose clothing and pull people into moving equipment. The same can also be said for the line shafts themselves. Keeping out of moving machines required considerable care and attention, both of which were hard to come by in the typical old bustling factory.

All of these problems could not be ignored, and when electric motors became smaller, economical, and readily available, factories began using machines powered by electric motors instead. Sometimes, entirely new machines were purchased that had motors built in. In some cases though, shops would refit their existing equipment to run without a line shaft.

Here is an example of an old drill press that would originally have be run by a belt from a line shaft. It has since had an electrical motor mounted on it, which turns the pulley that was originally used to power the drill. The adjustable speed pulleys are still intact, and the old mechanism has not been changed. In fact, except for the motor and an on/off switch, this drill press is virtually identical to what would have been found in any old machine shop. Home made conversions like this one, no doubt offered a cost effective way of running old equipment, even when maintaining an old line shaft system became impractical.

Today, this sort of system has faded out of use in most places. Your best chance of seeing a line shaft driven shop would be in a museum. If you get the chance, though, it's interesting to see a shop like this in action.

For a much more mathematical look at this topic, take a look at the belt and pulley page over at Harry’s Old Engine

Monday, June 25, 2007


I'm heading home from my latest trip very soon. (Singapore this time.) I'll need a couple days to get my feet back on the ground, but after that I have a brand new essay to put up, so stay tuned!

Friday, June 08, 2007

What kind of freight?

As strange as it may seem for air freight to go by truck, I think it would still be faster than waiting for flights right now. (I had the misfortune of picking a time and place to fly that corresponded directly to a national weather service thunderstorm warning.)

Tuesday, May 29, 2007

Quote of the unspecified temporal interval

True Blue Sam just referenced this quote. I think it's particularly appropriate considering the earlier post.

"For the want of a nail, the shoe was lost; for the want of a shoe the horse was lost; and for the want of a horse the rider was lost, being overtaken and slain by the enemy, all for the want of care about a horseshoe nail."

-- Benjamin Franklin


I know that necessity is the mother of invention, but these must be the red-headed step children.

Monday, May 28, 2007

Miss Me?

Once again, I'm back. Since my last significant post I've spent about 2 weeks in South Africa and some time in Ohio, but I'm back at home for about a week!

I'll be putting up a few posts soon, Starting with a brief essay I've been contemplating for a few months: The Mundane Detail

The Mundane Detail

If you’ve seen the movie ‘Office space’ then you probably remember the scene when the three main characters discuss how their money skimming scheme has gone awry and discover they will probably be going to prison. Michael, reveals what has given them away…

“I always do that. I always mess up some mundane detail.”

Yep, $300,000 and a prison sentence, traced back to a ‘mundane detail’

It’s the sort of thing that I have encountered too often. People don’t place value on things that seem simple or ordinary, but these are the things that often end up being important.

Shortly after I began my job, I was given a bit of advice. I was told that in spite of all the calculus and differential equations I had been taught in school, that the most important math skills to have were basic counting skills. Why? Because no matter how well you design parts, if you don’t order enough of them you’ll be throwing your work away. I realized this style of thought applied to many other things as well.

Here are a few examples.

It’s common for engineers to design a just few parts of a much larger system, in fact it is typically necessary because few people have the knowledge necessary to design an entire machine from the foundation up. One of the many problems arising from this is that incompatibilities may arise in a design. It’s worse yet if the parts cannot be tested, except at considerable expense.

In my first case, the parts being designed had to be taken overseas for testing. When they arrived, it was found that they were missing a feature that they required. It was a simple feature; three lines and a little text on the drawing would have solved the problem. But the parts had already been made when this was discovered. Even worse, tickets had been purchased, promises had been made to customers, and machines had been shut down in preparation for the testing. Three lines could have cost quite a lot of money if it hadn’t been for a stroke of luck in having a good machine shop nearby.

The second situation isn’t quite so nice. It involves a million dollar piece of equipment to be used as part of a much larger machine. It takes considerable work to properly install one of these, and there are plenty of other parts that are needed to complete the job. By comparison, these parts are inexpensive. A few hundred dollars worth of parts seems inconsequential compared with the overall price of the unit. If only that were true!

An error resulted in a few hundred dollars worth of parts not being shipped. Those parts weren’t available elsewhere, so when the shipment showed up without them it was a problem. There was no time to get more parts shipped, there was no local supplier, and no simple way to fix the problem. The only way to get around not having the right parts was to spend two days cutting holes in this million dollar piece of equipment while it was on the floor of a machine shop that is better suited to much less precise work. And that’s after waiting a day and a half for instructions from the engineering department, that had to be disregarded in the end because they were apparently not able to fully evaluate the situation from overseas.

The end result was a high potential for a botched installation, two or more days wasted production, and at least a man-week of time and labor thrown away. That’s worth quite a bit more than a few hundred dollars. And of course, whoever packed the boxes for the shipment, probably had no idea of the importance of those parts and the consequences of losing them. If every shipment was like that, he could go on shipping 99% of the parts that were ordered, and still leave all of his customers with a very low rate of satisfaction.

Mundane details like this are like quicksand, you’ll never know there’s a problem until you’ve stepped in it and start sinking. It’s an overlooked detail that partially responsible for my extended stay in South Africa. For what it’s worth, I was not the one who overlooked it, but that’s little consolation since things that aren’t my fault are often my problem.

Of course when forgotten details multiply, then things begin to look less like quicksand and more like a whirlpool. On a recent trial I had to rely upon four suppliers for parts and raw materials. The supplier I dealt with the most received a design which I had carefully checked, and I had multiple conversations to confirm the delivery date and address to insure that everything went smoothly. After all of that, things did indeed go smoothly, but not with the other suppliers.

One supplier made a part with a significant manufacturing error. Either through haste or misinterpretation of a drawing, the part was unsuitable for use without significant modification. (Modification that involved hand shaping metal that is supposed to be made to aerospace like tolerances. Talk about risky business!) That problem was solved, but there’s more.

The third supplier does much of their design work in house, and seldom provides details for fear of losing designs to other shops and therefore losing business. Because of this, it isn’t clear if the design was incorrect or if the manufacturing was simply sloppy with no inspection process. Either way, the equipment had to be jerry rigged to make it work, and as soon as the trial work was done it was boxed back up and sent back for rework. We lost time and the supplier will have to bear unnecessary expenses to correct the error. Still, the trial was still possible, or at least it was until the last supplier put the last nail in the coffin.

It turns out that some material shipped was unsuitable for the trial. Observations in the field indicated that it was probably not what had been promised prior to shipment, and might not have even been what its label said. We scrambled to do a few tests with other material, and we were able to confirm that everything else was working fine, but without large quantities of the requested material, the trial was essentially dead in the water.

All of the errors were simple ones that could have been avoided by a careful look at the parts that had been made or a little extra care in the manufacturing process.

Had I not been through trials like this before I think I would have been completely frustrated with the entire situation. Having a trial thwarted is bad, but having to solve all of the other problems first really adds salt to the wound. Still, there’s nothing to do but make sure everything is corrected then remember what went wrong so you can plan to avoid the problems in the future.

If there’s a lesson to be learned from this, I suppose it is that details can be simple, and even boring, and yet still be insanely important to your work or others, so try to stay sharp, and don’t overlook the little stuff.

An afterthought: I am not immune to this problem myself. I would like to comfort myself with the thought that the details I miss are more subtle than the examples listed here, but the truth is that nobody is perfect. Of course that doesn’t mean we can’t strive for perfection.

Wednesday, April 25, 2007

On the road

I was sitting in Narita Airport (Tokyo) earlier waiting for my flight home and I decided it was finally time to recap where I had been on this trip. Even these past two weeks it has been quite difficult to get away from the factory for any non-work related activities, so I really don’t have anything new to report since leaving Africa. I suppose that’s just as well though. I’ll need to spend plenty of time in Singapore and Thailand in the near future.

It’s been quite an eventful trip, but mostly because of work related matters. I only had a few chances to go out and sightsee, and that was all in South Africa. Still, it was quite nice and I did enjoy it quite a bit.

In South Africa, the crew was working a cycle of 4, 12 hour days then 3, 8 hour days. I had a couple days off during the month and did use that opportunity to go see the Suikerbosrand nature reserve, which was very close to where I was working.

The Suikerbosrand is a nice quiet place, often favored by hikers both for day or week long trips. If you don’t have the time or the gear for a proper hike, you can always take the tourist loop driving trail around the reserve. The reserve contains most of the mountain range of the same name (which in turn is named for a type of shrub found in the area.) The mountain range doesn’t exactly measure up to the Rockies, or even the Appalachians, but if you consider that most of the region is a mile high to begin with then the peaks are pretty high up. And the views are certainly impressive.

The whole region is highveld grassland, meaning that it’s a very arid, somewhat prairie like environment with few trees and plenty of grass fires (which are often allowed to run unchecked if they do not threaten an inhabited area. Combine that with the red soil, and it looks like Arizona with tall grass.

This particular region has basalt (igneous) inclusions into a sandstone (sedimentary) layer. Consequently, over the years, the softer sedimentary rock has eroded away, leaving rather prominent peaks and ridges made of basalt and a thin layer of soil.

The higher regions of the reserve have relatively limited wildlife activity, because they are so dry and sparsely vegetated that there is little cover and less food for herds. Of course if you get close to a watering hole, then you usually see quite a bit of wildlife.

In this reserve is mostly populated with eland, wildebeest, and zebras. Occasionally you will see some Hyenas, but you don’t encounter large animals like elephants and rhinos or predators like lions. Of course this lack of the most dangerous African animals probably explains why there are so many hiking trails in the area.

I did get to see one predator while I was in Africa though. One of the local wildlife officers stopped by the factory to show some friends a ‘little’ tiger cub.

It played just like an ordinary house cat, but I would really hate to get it mad even at a fairly small size like this.

I did get one extra treat on this trip, thanks to a colleague at work. South Africa was using steam locomotives in regular operation as recently as the early 1990s. Occasionally you might find one in use, but the only time they are really seen now is when they are being run for railfan excursions. Luckily for me the railyard for Rovos Rail, a company that specializes in running regularly scheduled steam excursion trains, is just North of Johannesburg.

This coworker and I took a few hours on an afternoon when work ended early to go see the railyard and the Pretoria railway station. The station was quite an incredible piece of work. It was registered as a historical landmark for many years, but was recently burned down (arson, I’m sure) and had to be completely rebuilt. The rebuilt version is quite beautiful, and since it had an old steam locomotive on the platform we stopped in to look at it and take a couple of pictures

We talked our way onto the platform and I was about to snap a photo, when a Metrorail official on a power trip stopped us and said that we were not allowed to take pictures of the locomotive without first getting permission from the marketing department. His line of ‘reasoning’ was based on the idea that images of the engine could be used in a negative manner and hurt the tourist trade as well as their standing with local customers. Never mind the fact that the marketing department was closed that day and that the locomotive had been built decades before any current railroad employees were even born. So rather than having a cheerfull comment and a photo of a steam engine, I now have a story about how an official of Metrorail was simultaneously uncooperative, illogical, and rather rude.

Thankfully, the day did not end there. The people at Rovos rail know how to promote tourism so when I stopped by the yard I got to take pictures of their locomotives from the inside and out. After a nice chat with Mr. Rohan Vos (the head of the company) we were free to roam around the yards so long as we didn’t go into the engine shed and distract the men working there. So I managed to snap a few nice shots before being chased inside by a thunderstorm.

A fun as it might be playing with tiger cubs and running around nature reserves with a camera, I have finished (for the time being) my work overseas, and now I am back in Chicago. The weather is much nicer than it was when I left. (It’s not sunny, but it’s not bad.) Of course it has been a while since I was here. The last time I saw the Chicago skyline, there was still quite a bit of ice and snow on the ground.

It should be nice to be back in town for a while. Of course, it is a bit of a switch considering some of the places I have been lately.

Friday, April 13, 2007

One month later

No, I have not been eaten by lions, trampled by elephants, or swallowed by a crocodile. (I was however, laughed at by hyenas.)

I've just spent a month in a place where checking my email usually involved checking for a dial tone. I have now left South Africa for Singapore where I will be spending a few days before continuing on my way.

The trip so far has actually been rather nice, though far from relaxing. South Africa was rather enjoyable, though I won't go into the details just yet.

I have some photos to share and will post them in a couple of days when I get a little time away from the factory. I the meantime, I will leave you with this.

Friday, March 09, 2007

Quote of the Unspecified Temporal Interval

Most travel is best of all in the anticipation or the remembering; the reality has more to do with losing your luggage.
~Regina Nadelson

As you might have guessed, I am travelling again, and this time I'm out of the country. I landed in Johannesburg yesterday and expect to be spending a few weeks in the area (on business of course.)

I'll put up a few posts whenever I get the chance, and hopefully I'll get to do just a little sightseeing before I leave.

Thursday, March 01, 2007

Winter's last hurrah

It looks like we're getting the first of the spring storms in Chicago. I'm not sorry to see winter go, but I am sorry to be leaving right as the weather gets nice. Next week I'm starting off on a trip to the southern hemesphere and equator. It should be fun. Too bad I won't get back until mid to late April.

Friday, February 23, 2007

The easy way or the hard way?

I've been neglecting the blog a bit lately for various reasons, and I thought it was about time to put up a post or two before I forget how.

Just the other day I glanced at the cover of the Model Railroader magazine and was delighted to see a cover story touting a tour of a largely scratch-built layout. In years past this might not have made headlines as virtually every layout they featured was full of scratch-built structures. More and more though it's possible to recognize the models in the MR articles.

This layout featured a number of pieces that were hand built out of highly detailed craftsman kits or constructed completely from scratch. This gave everything a very fresh, unique look and made it possible to experience the sort of suspense of disbelief that allows you to look at the railroad as though it is real. Sadly, it seems as though thisapproach to the hobby is largely disappearing

Recently I visited the "Great Midwest Train Show" in DuPage County. After searching the show and finding only a couple of antique kits that interested me, I struck up a conversation with one of the dealers about how hard it was to find craftsman kits andscratch-building materials. It was his opinion that quality kits were only going to get harder to find while more and more ready to run and quick assembly kits were going to take over the market.

After thinking it over for a bit I had to agree with him

Several years back, I purchased what was, at the time, the only commercially available kit for a CB&Q waycar. It was a LASERkit model which means that it was mostly wooden pieces cut on a computerized laser cutter. It was quite complex and took several hours on several evenings to complete. It was quite satisfying to see it finished. A year or so later, Walthers came out with the same waycar in a nearly ready to run version. The price wasn't too out of line with what was already on the market, but the new kit could be put together in about a half an hour with a bottle of superglue. Now the model is down to about half of the original cost.

The one without weathering is the simple model.
The wooden model is the one with the handrails removed.

They're both good models, and look quite similar (though I will admit a certain fondness to wooden models) but the more complicated kit gives you a feeling of accomplishment, while the simple one just sits there and looks nice. It would be a shame for model railroading to become something as simple as buying models and setting them on the rails.

Here's an example of what most people would consider a craftsman kit.

In the 1930s and 1940s when this kit was originally sold, it was considered a pretty standard kit. I picked this up at a model show in Green Bay a few years ago in roughly this condition. Apparently theprevious owner had done some work then abandoned it when it didn't run smoothly. It turned out that the mechanism that held the brushes against the armature of the motor was damaged (and poorly suited to the task.) So I simply replaced it with a spring system of my own (loosely based on other designs) and now it runs great.

I plan to build up this kit to a finished model as soon as I get a chance to sit down and really work on it. I could drop about $160 on a modern, ready-to-run model that would probably have a quieter motor and marginally smoother operation, but that defeats the purpose of having a hobby. If all I did was buy the models I wanted, it would just be collecting, and not model railroading.

So if I may offer a bit of advice, if you have a hobby (and almost everyone does) make it worthwhile, and put some actual effort into what you do. If it's collecting, learn some history about what you have, not just the values. If it's a craft, make something the hard way and see how you like it. I bet you'll have more fun that way

Friday, February 02, 2007

Wake up campers,


Yep, that's my father, me and a groundhog having a bad day. I'm afraid I can't take credit for the shot though. If the glasses and eyepatch are any indication, I couldn't have hit the broadside of a barn at the time...even with that lovely Ruger .223!

Sunday, January 14, 2007

Saturday, January 13, 2007

Thursday, January 11, 2007

Powerhouse to barnyard - The gas engine

In my earlier post ‘The Powerhouse’ I covered a little about stationary steam engines and the technology behind them. If you’ve already read that, or if you know a few things about steam engines, you’ll probably find that you understand a great deal about antique gas engines as well.

Gas engines (or more appropriately, combustion engines) were basically the next evolutionary step in the development of machinery and machine operation. They were often made in a format very similar to that of the existing steam power of the day. A cylinder was mounted (often horizontally) on a frame, it held a piston connected to a pushrod that turned a crankshaft, flywheel, and pulley.

The general appearance of steam and gas engines is often quite similar, but the method of obtaining power is somewhat different. Naturally, while a steam engine’s power is supplied by a boiler, a gas engine relies upon some combustible liquid or vapor being ignited in the cylinder. Unlike most steam engines, the power is supplied on one side of the piston only. In fact, while a steam engine can be powered through almost all of it’s stroke (except the very end) a typical gas engine ran on a 4 cycle system where power could only be provided about a quarter of the time. Like many steam engines, this energy was used to turn a flywheel which smoothed out the flow of power from the engine.

There were other differences as well. Combustion can produce high pressures from relatively small amounts of fuel and air, so the huge pistons and valves seen in steam engines were not necessary. Of course the power stroke of a combustion engine can be rather violent so sturdy bearings, and crankshafts were necessary.

The control methods for these engines also had strong ties to their older steam engine counterparts. Typically a centrifugal governor was mounted somewhere on the engine either by taking power from the crankshaft, or by putting governor weights directly on the flywheel. Here’s an example.

On this engine, made by the Abenaque Machine Works, a small driveshaft is geared to the main crankshaft (behind the flywheel) This shaft has two weights (painted red) which are pinned in place so that they can pivot away from the shaft when they’re spinning quickly or be pulled inward by a spring at slower speeds. This is the same principle as in the steam engine governor from my ‘Powerhouse’ post. The way this principle is used, however, is noticeably different.

Achieving reliable and controlled combustion requires a consistent fuel supply and the ability to thoroughly mix the fuel with air. Fuel injection was unheard of when engines like this were first being built. Even good adjustable carburetors weren’t available for the early years of these one cylinder machines, so creating a reliable and controllable fuel supply for every stroke was not really an option. Even if the designers of the first gas engines had been able to provide a precise throttle and carburetor system, it’s questionable it would have been a success. Many engines were expected to run on multiple fuels, including gasoline, various grades of oil, or natural gasses. This no doubt created too many variables for early gas engine technology to compensate.

The solution found was the hit and miss style of operation. On a 4 cycle engine of any kind, it’s possible to have a power stroke on every second complete revolution of the crankshaft, but what’s the point of having a power stroke when you still haven’t used the energy from the last one? When a gas engine provides more power than is needed, it’s simply stored in the flywheel, so that the engine keeps running regardless of whether or not another power stroke is made. Because of this, all you have to do is keep the exhaust valve open to relieve pressure in the cylinder, and the engine will coast for a while after making a power stroke.

Here’s how it happens. An engine is running at the speed set by the governor. A load is applied to the engine (usually by way of a belt to some other machine.) This slows the engine down, so the weights of the governor are pulled inward by a spring or counterweight and this triggers some type of cam or linkage. The engine’s exhaust valve closes, the intake valve opens briefly to allow fuel and air to be drawn into the cylinder, and the piston compresses the mixture in the cylinder. A spark from the magneto and spark plug ignites the fuel and the piston completes its stroke under power, causing the crankshaft and flywheel to accelerate. The acceleration causes the weights on the governor to be pulled outward. The exhaust valve opens to allow the spent fumes to escape, and it is held open because the governor is now moving fast enough that it is not necessary to make another power stroke. And the cycle begins again.

The sound of an engine like this is pretty unmistakable because you can hear it fire once and then it will usually ‘chuff’ softly several times as the piston cycles with the exhaust valve open.

The introduction of combustion engines created the need for another design change. The hottest part of a steam engine is steam that comes from the boiler. Even a boiler with a superheating system would never produce steam hot enough to melt steel. (If it did, it would melt the boiler.) Consequently, the steam cylinders, though hot to the touch, did not require a cooling system to maintain the integrity of the metal. Gas engines, however, had the ability to produce temperatures that would soften or melt most steels. This meant that new systems had to be invented to keep the gas engines cool as they ran.

A simple method of keeping a gas engine cool was to add cooling fins. Much like the computer cooling systems of today, this approach increased the surface area available to expel heat by means of heat radiation or convection. Such designs were often quite simple as in the case of this model gas engine, which has a set of fins around the outside of the cylinder.

Another method of cooling was commonly used on gas engines to keep them from overheating; the cooling tank. The basic explanation is that if you stick a pot of water on top of a gas engine’s cylinder, it won’t overheat because as soon as the water gets to 212F the water will start to boil away and take the excess heat with it.

The design of the tank varied from engine to engine, sometimes becoming a bit artistic, but typically it was just a rectangular tank mounted on top of a cylinder. Of course these engines were made with a water jacket around cylinder to cool it from all sides. On smaller engines, it was even possible to build the engine so that the tank was the only thing visible, and the cylinder simply ran through the tank. If extra cooling was needed, water could even be circulated through a radiator, much like on a car.

Of course I can't talk about cooling without mentioning this circa 1912 Aermotor. In this case, a tank with cooling fins was mounted vertically on top of the cylinder. This was likely intended to help increase the amount of convective heat loss, because the air which is heated by the fins will naturally tend to rise, creating more circulation along the length of the fins. Also, this design shed enough heat that you didn't continually need to add more water to the hopper (which was quite common in open hopper engines)

Of course, these fins also have the effect of making the engine look a bit outlandish.

Over all, gas engines tended to remain fairly simple in design for many years. This could likely be attributed to the fact that farms were the most common place to use a gas engine of this sort. If the engines were made too complex or require too much maintenance, they lose their usefulness in this environment. Eventually carbureted engines would become more common, as the improvements in design and manufacturing made it possible to control an engine by its fuel supply rather than simply using hit and miss operation. Much of this development was no doubt driven by the development of automobiles and tractors which required more powerful, smoother running engines. Still, these small engines were a familiar sight until electric motors became strong enough (and common enough) to be used in their place.

While your typical combustion engine was found on a farm, powering small pieces of equipment, there were other engines which were much larger and much more complex. Larger engines were needed in many applications. Factories, mills, power plants, ships, and other heavy equipment needed power too, and although they had relied upon steam in years past, many of them converted over to combustion engines.

These applications required plenty of power and long hours of operation, meaning that the engine had to require very little time for servicing and repairs. This is where diesel engines really shined.
Some of these engines still had the same cylinder and flywheel arrangements as their barnyard counterparts, but they they were usually noticeably larger, and it was fairly common to see them made with multiple cylinders.

These engines are not easy to come by, but when you get a chance to see one in operation it’s quite impressive. Here’s an example of a page engine which was originally used to power a drag line.

Today this beast resides in the powerhouse museum on the Mt. Pleasant fairgrounds. It’s a two cylinder diesel manufactured by Page Engineering Company (Chicago IL) where it has been restored to running condition. This engine produced 110 hp. When you consider the horsepower cranked out by today’s automotive engines, this may seem rather small, especially for an engine with 13” bore cylinders. Still it was quite powerful for an engine in its time.

The best part, though , is watching (and listening to) this engine run.

Next time, more on the use of stationary engines (gas and steam.) Stay tuned!