Broom Pilot

Although we live in a pretty good neighborhood, as a bit of added security I posted a Broom Pilot to cruse the yard and keep an eye on things. Don't worry she is the good kind, only casts good spells.
Soon as I got her up the dear old 80 plus year old world war two air force veteran from across the street came over and informed me that the broom engine was a Kenner 5, and then he wondered why the push rods and rocker arms were not vibrating like they should. I could not tell him, I don't know much about broom engines.

For a little background, the tubing parts are conduit, and all the sheet metal was salvaged from a clothes drier. That is good stuff. It is plentiful, it is a nice thickness to work with, and it has been treated so it does not start rusting as soon as it is placed out in the weather. Everything that moves does so on ball bearings. The propeller shaft is the rear hub and axle from a 10 speed bike, and the whole thing swivels on pedal bearings, from the same bike. The face was the most difficult part. It was formed by pounding the metal on a piece of thick rubber on the anvil. The hair was a snap; I just cut strips in metal and then styled it like a beautician. Would you like your hair styled?
Birk

Machining Helical Gears

A little over a year ago I built a scale model Gatling gun. For this project I needed a pair of helical gears. They could have been purchased from a bearing supply house, but there is not much satisfaction in buying something that someone else has made when you can do it yourself.
If you think about it, a helical gear is a short section of a vary course pitch screw with multiple leads; as many leads, as teeth in the gear. Theoretically you could machine a helical gear in a lathe, but actual practice and theory do not always coincide. However if you set up a work holding spindle on the mill table, that represents the lathe spindle, and gear it to the table traversing screw, that represents the lathe lead screw, the theory works great. By the way I did not invent this idea, I just adapted what others had already done to my own mill.



A bracket was built and several gears machined that will remain a permanent part of the fixture. Note that I even installed reversing gears, just like on a lathe, so it will machine both right and left hand helix. Then change gears are needed in order to get the proper ratios, and I just used the gears from an old antique lathe in my collection. It took an extra pair of reduction gears more than used on a lathe, but that was worked in too. When it was all put together the counterbalance knob on the regular mill handle hit the gears so I had to make a new different shaped handle.



To figure the ratio, you need to determine how far the mill table would have to travel for the work piece to rotate one revolution. Then divide the the table screw pitch (mine is .200") into that, and that is your ratio. Simple as that, well almost. The gear I was machining was specified as 1" pitch diameter, therefore the long travel at 45 degrees would be equal to one times pi. Now pi is not a very nice number to try and factor into a nice ratio. I had several choices. I could machine a couple more change gears of the desired ratio for a one time use. I could change the helix angle slightly so the long travel would come out to a nice even number, or I could change the pitch diameter to make the long travel come out even. I chose the latter, as it only required changing the pitch diameter by a few thousandths of an inch. (I cannot remember for sure, but it was about .015") The housing holding the gears had not been made and so when I got to that part it was only a matter of spacing the center distance of the gears a few thousandths different than what the drawing specified.




The mill head was tilted to get the cutter in the same plane as the helix. I used a hand ground one tooth cutter for this job. The big work holding spindle drive gear had a multiple number of teeth of the blank I was working on. One grove was cut, Then the gear train carefully loosened and the big gear turned the proper number of teeth and re-engaged, and the next grove cut, and so on.



The last picture shows the gears after I finished cutting all the teeth. The gears were installed in the gun and it functions beautifully.

Now I have the means to pursue one of those little side shaft engines that I have wished for, for so many years.
Give it a try, you might surprise the heck out of yourself what you can do.
Birk

Cutting Gears

This morning I went out and machined the teeth on a couple pinions. This is the last two of twenty three gears required for the model steam shovel presently under construction. These two will work in unison to push the dipper stick out and in.

I do not know how many viewers of this blog machine their own gears, but it is not a difficult task. When you look at all the charts, tables, math, etc. it is scary. But I have taken the attitude that if the early settlers could make working gears for their grist mills and sawmills, etc. by pounding pegs in a log, then shame on me if I cannot make a gear on my milling machine. Over time I have collected a few commercial gear cutters, and they are nice, but most of the time I do not have the right one and end up grinding a lathe tool bit for a single tooth cutter. You can use a gear of the same pitch and very near the same number of teeth as a template to fit the cutter bit to. Most often I make a layout using the drafting table, and grind a bit to fit my layout. The small paint brush is wetted with cutting oil and held next to the cutter so the bit wipes through the brush providing a film of lubrication each round. It is a lot cleaner than a flood system, for such little jobs.
Birk

Deck gun

If it were not for guys like me old man Lindsay would probably be living in the poor house, rather than in that Mansion on the hill. Another book that I bought from Lindsay Publications is reprint of a 1922 book, "Lathe Work For Beginners". It is pretty interesting if you like reading about old obsolete stuff. After it tells all about setting up and running a lathe, there is a deck gun project shown in the back. It looked interesting so I built a modified version.

It is built to be functional with a .22 barrel. It has a falling block that allows loading. The whole action slides back when it recoils just like the big ones. There are horizontal and vertical movement hand wheels. Living so far inland, I'm not exactly sure what they use deck guns for, but I believe they world work great for "Decking" dogs that poop on your lawn.
Birk

Post Drill

You know, my wife and I actually have interests in common; Babies. Of course she prefers the people kind, grand babies, great grand babies, other peoples babies. Where we differ is that I prefer the mechanical kind. I seem to have this warped mind. Most often when I see a full size mechanical something or other, I have a desire to make a "baby one" of it. So I turn out babies as fast as I can work them into the schedule.

Today's baby picture is of a blacksmith post drill. The reason that they are called a post drill, is not because they were made to drill posts, but because they ware almost always mounted on a post or column the the old workshops. This one is a 2" scale model of a full size one in my collection of antiques. To give an indication of size, the base it is mounted on is 3/4" thick. I hope you like looking at it.

Bug!

That is one of those dangerous West Nile varieties. If you see one of them buzzing around, you had better arm yourself with some bug spray-- quick! Because as you can see they are hungry Buggers.

Non-Identical Twins

A while back Rowland Manufacturing Company in New Washington Ohio advertised model engine castings in just one issue of Home Shop Machinist magazine. Normally I do not buy castings, but these looked kind of unique and the price was reasonable. I believe it was a college student using his new computer design skills to design engines, same as POWDER KEG does. He had done a lot of work and had designs so the engine could be made into any kind of piston engine, gas, steam vacuum, etc. He sold the castings and plans separately. In order to maintain a little personal identity of my own I just ordered castings and made my own plan. When the castings arrived, in order to get more than my money's worth, I used the castings as patterns and poured a send set. One engine was fitted with an eccentric and a spool valve. The other with poppet valves. They are also timed to run on opposite directions.


Nothing spectacular, just more engines to look at.
Birk

Which Way

I'm a little slow getting a post today, because the first priority of the day was to get about 4" of that famous Utah powder cleaned off the drive and walks.
That Surplus Center place in Nebraska had a "grab bag" special on pneumatic cylinders; 10 for $20, their choice. So I placed an order, I like surprises. When the package arrived it was opened and one of the Bimba cylinders had a rod sticking out both ends. I thought what will I ever use that thing for. Then all of a sudden the little light blinked on in the attic. How about a double ended engine?

I already had a flywheel pattern that would work, and being symmetrical it only required a couple new ones. It has a rotary valve that rocks through an arc of 90 degrees, operated from a crank on the right end. The wheels on the right always turn the same direction, because they are timed with the valve, but the ones on the left can rotate either direction, depending on which way they get started. What is it good for? Like most of the other stuff I build, nothing,---except perhaps a bit of amusement.
Birk

Flame Licker

It seems that sooner or later almost every model engine builder makes a vacuum, or fire eater engine. I'm no exception, so here is a picture of how it turned out. The visual exterior appearance is of my own doing, but the actual working mechanics were borrowed from Phillip Duclos.

Work Bench

I ordered from Lindsay Publications, one of those wonderful "Model Engineering" books written by Henry Greenly in England, and published in 1915. That century old book is as interesting today as it was when it was new. In the first chapter Mr. Greenly discusses setting up a shop for model building; space, tools, machines, etc. One of the highly recommended machines was a hand shaper. Shapers must have become obsolete cause I could not find one, so I proceeded to make my own, by looking at the picture in the book. There were no dimensions given so I just had to guess at them. Therefore I do not know if it is the right size, but here is a picture of the finished "hand" shaper.



Another very important tool was a good bench vise, so I proceeded to make one of those to go along with the shaper.


Then they were mounted on my workbench. As you can plainly see, I'm now ready to tackle any small job that comes along.


Yes, the tools all work! The files for instance, are tips from needle files. The tin snips will cut foils, though its just hard to get your fingers through the handles. The brace actually has a working chuck with jaws like a full size one.
Birk

Spoked Wheels

Today I'm in the process of machining some spokes cable sheaves for the steam shovel. The operations are similar whether your making a sheave, a gear, or a flywheel. I thought that those new to the hobby might be interested in the process. These are fairly small being 2 1/2" diameter and 3/8" thick. First rough blanks were sawed from some plate steel, then blued and laid out. Under size pilot holes were drilled at what would end up being corners. A hole was drilled and reamed in the center. It will eventually be fitted with a brass bushing. Then the blank was put on a mandrel where the O.D. and sides were turned in the lathe. On this particular job I drilled a 3/8" hole in the center of each space after turning, just to hog out some metal. I don't always do that. Then the part is moved to a three jaw chuck on a homemade rotary table on the milling machine. The circular arcs are milled by simply turning the table and leap frogging over the spokes. The sides of the spokes are milled by traversing the mill table, and indexing the table the proper number of degrees for each spoke. Spokes are nearly always tapered from the hub out to the rim. These sheaves have a 6 degree included taper. That needs to be taken into consideration when setting up, but is easy enough to do with the rotary table.


The first picture shows a sheave in the process of milling the spokes, and the second picture shows two sheaves. One after turning, but before milling, and the other one after the spokes have been milled. The spokes come out rectangular in shape, and the could be rounded of with a radius cutting mill, but it is hard to find a cutter the right size to fit those tiny spaces. So I just use a file, and within a couple minutes can have the corners rounded enough to look ok. The rounding is cosmetic anyway, so it does not matter if it is not perfect.
Try it you might like it.
Birk

Beam Engine

Although maybe not the most efficient design for a steam engine, beam engines are certainly interesting machines to watch running. Anything they lack in efficiency is more than made up in entertainment. The beam engine posted here today is a little more refined than the Coffee Engine that I posted yesterday. This engine very closely follows the Stuart Turner beam engine drawing, but I made my own patterns and castings, and that allowed me to add a few of my own embellishments.


For a simulated masonry base, I reworked a little cutter similar to a slitting saw. It was put in the mill on a extended mandrel and set at the height of a mortar joint, and then I slid the casting past the cutter by hand to scribe the joint. Then the elevation was changed to the next joint line, and so on. The vertical joints were chiseled in with a graver and a small hammer.
A flyball governor was an optional accessory on the Stuart engines and I had no drawing for that, so I simply designed my own. It works nicely, controlling the speed of the engine. I have it set a slow pace which makes it more realistic. Working from someone else's drawing is sometimes easier, but I spent over forty years working at a large metal fabrication and construction company, much of that time doing design engineering, so it comes quite naturally. The only difference between models and the real thing is simply size.

Half Beam Engine

After building the Beam Engine that I posted yesterday, I built a Half Beam engine. I have no idea why they call the half beam, because they still use the full beam. They have also been referred to a grasshopper engines because the action somewhat resembles a grasshopper leg. It only required making two new patterns. One for the A frame on top the cylinder and one for the rear beam support.


The brickwork for the foundation was cut in the same was as for the beam engine, only on this one, after the brick red paint had dried, it was sprayed with an off white paint and immediately wiped off with a rag. This left some white in the grooves and smeared a bit on the face which gave it a rustic aged appearance that I rather like.
An advantage of making your own patterns and pouring your own castings, is that you can make them unique to your own workshop as seen if you look closely at the rear beam support.
This engine does not have a governor.
Till next time
Birk

Steam shovel update

After setting nearly a month being dormant waiting for drawings to be made, and then followed by parts being cut and fabricated, my baby steam shovel sprouted a thing on the front late yesterday. I'm not sure just yet, but I think that means that it is going to be a boy one.

That is hardly a start on the boom, there is so much still left to do on it. In fact right it is now only being held up in place with a piece of wire. It needs to come off to be worked on some more, but I have to do things like that once in a while to spur my enthusiasm. Anyway Wes said he wanted to see a progress picture.
Birk

Ball Turner

A ball turner is kind of a unique accessory for your lathe. Most every machinist at one time or another will have a need to turn spherical shapes. The easiest way is with a ball turner. You can buy one, but they are simple enough to make yourself, and there are all kinds of instructions out there on building them. Usually the cutting tool travels in a circular arc in a horizontal plane or else in vertical plane along the centerline of the workpiece. I have built a couple of them, one quite large with a capacity of about 6" diameter and the other smaller, with maybe 2" diameter. I'll just show the small one today. I need to mention this is a demonstration picture. Normally when I'm turning ball ends I hold the work in one of those 5C collet chucks. That way I do not risk having the chuck jaws strike the ball turner, and cause all sorts of commotion.



On this one I used some features of a plan that I found, but modified it so that it would work on the quick change tool post. I have found it handy for making the balls for fly ball governors, ball ends for guard rail posts for railing around models, etc. One use was to form the ball ends on a helping hands work holding fixture for silver soldering.



For this demonstration picture I just clamped three pieces of brass and positioned them together. From here it would be a simple task to daub the joints with flux and silver solder it together. To assemble that same configuration without the fixture would be a difficult task.

By the way if you do not want to build your own helping hand fixture Harbor Freight has an in store coupon sale going on right now, till Feb. 11, for $1.97. (normally $3.99) It is smaller and does not have as many joints to move and position things as my home made one, but at that price I could not pass it up, even though I already had one. They also include a magnifying lens. Take that off attach a nice handle and do a little detective work on the side.



In closing I suppose a ball turner could be compared to a bull on the farm. It is not the amount of work it does to earn his keep, it's the occasional service it performs.
Birk

Table Engine

Here is a third engine that I built following Stuart guidelines for their series of models that use interchangeable parts. This one comes with several names too. Elmer Verburg built one and called it a mine engine. In the Stuart catalog it is referred to as a James Coombes engine, possibly because of the original builder or something. The table calling comes from the fact that the cylinder sets of a platform supported by four legs like a table. In the Stuart catalog it states that the original prototype engine had a 10" bore and 24" stroke, and produced 20 hp at 40 rpm. It also stated that it was used at a Bristol colliery for more than 100 years. Wow! How many machines now days last that long? A lot of people feel lucky if their car lasts long enough to get it paid off.

Most of my engines are painted gaudy contrasting colors, because it makes them so photogenic, but I figured ant engine that had spent 100 years working a a coal mine would be black. The color might be right, but it sure makes it hard to photograph so that you can see it properly.

There are at least three more engines in this series that I have not built yet. I have to compare myself with a young man on a big college campus with thousands of girls. There is simply no way that all of them can be pursued, You just have to make do with what ever number you can work into the schedule.

Birk

Unicycle Dude

At our place I try to have something of interest for every size and age of people folk, so why not a Unicycle Dude. The first picture shows a close up right after he was built. The second shows him on the high wire (cord) in one of the display buildings. One end of the cord is stationary, and the other fastened to a lever that moves up and down. That action causes his little legs to pedal that cycle as fast as he can back and forth across the building. He has pretty good sense of balance. He has only fallen of a couple times when someone bumped him.


What is not shown in the pictures is the mechanism that makes him go. Down on the wall is a little crank that is within easy reach of even little people. That crank is connected to gears and then a drive shaft up the wall to more gears and another crank and finally to the lever. You know, whatever it take to keep it mechanical. I'd post a picture, but that part does not photograph very well.
Birk

Lubricating sealed bearings

have devised a pretty slick way (pun intended) of lubricating sealed bearings. It is so simple and non destructive. The bearings are placed in a container just big enough to hold them. In this case, a little plastic cup. Oil is poured over them until they are completely submerged. Normally I use 90W gear oil. Then the cup is placed under the bell jar on the vacuum table, and a vacuum pulled which extracts the air. As you watch you can see the air being pulled out of the bearings and bubbling up through the oil. After a moment or so release the vacuum and oil will be sucked into the bearings to replace the missing air.

I've lubricated lots of bearings this way. Usually they get over filled so they leak a bit until the excess drains out, but that is ok. I've re-lubricated electric motor bearings that sounded like they were wore out. The bearings in my 50 plus year old table saw sounded like a grist mill until I lubed them. Now they are quiet as new ones. One time I ran onto some new-old stock bearings that had set on the shelf so long the grease had hardened rendering them useless. Some fresh oil to soften the grease and and they are ready to roll again.
Not every shop is equipped with a vacuum table and a bell jar, but something as simple as a 1/2 pint canning jar with a hose fitting soldered to the lid would work fine. There are lots of sources for vacuum, some people could even hook it up to their head. A vacuum cleaner would probably not draw enough. You need at least 15 inches. Those hand pumps that are used to bleed hydraulic brakes would work, there are aspirators available. Even condensing of steam in a closed chamber.
Play a little, you will have fun with it.
Birk

Bimba

An easy quick way to build a lively little engine is by using a pneumatic cylinder. Air cylinders can often be found at flea markets and swap meets, etc. The Surplus Center in Lincoln Nebraska has bushels of them. This engine has a simple spool valve and is connected with plastic tubing. The crankshaft bearings are from roller blade wheels. Skate boards, roller blades, and those little aluminum scooters are all equipped with ball bearings, and the bearings usually outlast the treads on the wheels so they are a good source for little bearings for your engines.

Although the cylinder on this engine is not a Bimba brand, I named it that anyway. The Baby Bimba shown below does have a Bimba cylinder. In fact the factory decal is still on it

It is a real little hummer, with a 1/4" bore by 1/2" stroke. I sort of suspect that is the smallest cylinder that Bimba makes.

Grasshopper or Half Beam Engine

The engine above is a Grasshopper or Half Beam engine. The one to the right is a Beam engine, and the black one in the background is a Table engine. All three were built from Stuart drawings, and they share a lot of interchangeable parts. (Castings)