How it all started…

My wife was buying some plants for the back yard so I was checking out the gurgling, bubbling fountains and waterfalls on display in the garden center.  You’ve probably seen the dolphin spewing water from it’s mouth, cherubs, and other cute statues that expel water, so I had an idea: I would get a small child’s plastic swimming pool, sink it flush with the ground, put some wood planks over it, find a small hand pump, buy a small working windmill, and have it pump the water from my “pond” into a little bucket which would overflow back into the pond.  I just knew I would enjoy looking at a little windmill turning in the breeze much more than looking at one of those fountains.  Well, I quickly found out that no one makes a miniature working windmill (at least not an authentic looking one), and the small windmill/hand pumps looked OK, but were not functional.

Several years ago, an attempt was made by an individual (he asked me not to mention his name) to build an authentic looking model that he planned to market as a non-functional lawn ornament.  The cost of building these units was a little more than he expected so he abandoned the project.  I was fortunate enough to find one of the three prototypes.  I was elated because it was just the right size for our yard…32 inch wheel, 11 foot tower – and it looked much more authentic than the typical "yard models" I had seen…

(To describe each and every phase of this attempt is beyond the intent of this article and my time available to do it…so I’ll touch on the highlights.)

I purchased the pump from American Windmills (in the Marketplace – Company Ads section) since it is 24 inches tall (perfect size for the above mill) and looks very authentic.  I figured I could put a working piston in it and make it functional fairly easily.  I still had plans of somehow designing a gearing mechanism to get a pumping motion out of the model mill.  Incidentally, the model’s gear case was a hollow piece of 4-inch pipe so I figured there was room for small gears.  When the pump was delivered I was amazed at how realistic it looked and thought with just a few modifications, I could REALLY make it look good…and that’s what turned this into more than a years worth of work.  Some of you have been there, I know…just change this a little, and that piece would look better if…before you know it you’re practically redesigning the entire subject.  Which is exactly what I did.

…so I started with it.  Actually, you could use it as it comes out of the box.  It is painted bright red but I wanted the “weathered” version so I did spend some time with the airbrush to obtain this effect.  It also comes with a ¼ inch round aluminum piston rod so I changed it to a rectangular steel type, which I think is more commonly used for windmill/hand pumps.  Plus a few other cosmetic modifications, but those were the major ones.  (Those “few other cosmetic modifications” caused this stage to take over a month!)  

The wheel was the hardest…

The Aermotor purist will quickly note this model is a contradiction to itself: the hub I chose was the latest 802 design because it seemed to be the easiest to model, yet the rest of it is modeled after the early 602 series.  My brother Doug’s is a 602 so I tried to copy it.  My friend and Master Welder, “Big Dave” Dyess, and I laid out the wheel by hand and I’m still amazed how close we came, especially on those compound angles required for the spokes.  I used 5/32 round cold rolled steel and cut 8-32 threads in both ends – one screws into the hub and is secured with a jam nut; the end that goes through the outer band has a square nut on the outside (to look authentic) and a hex nut on the inside to facilitate truing it up.  It runs surprisingly true, but it took several hours of adjusting the tension on each spoke to do it.  The sail ribs were scaled from a real one.  Dave used a scroll saw to cut out those 18 sail ribs – a long and tedious process - you will break lots of blades before you’re finished and your fingers will hurt from pushing so hard on the metal!  Overall, I’d say the wheel took at least 3 months to complete.  

Lots of welding on the gear case…

Like I mentioned, the main part of the gear case is just a 4-inch piece of pipe on which we welded sections of smaller pieces.  Watching his 50 amp Plasma Torch do its thing on thick steel and pipe is pretty incredible and sure saves a lot of hack sawing!  All welding was done with a 250 amp wire feed MIG using .023 wire in a shielding mixture of argon and CO2.  "Listen to the frying bacon", Big Dave would always say as he adjusted the settings.  Welders talk (wink).  The main shaft is 5/8" steel dowel rod welded to the front of the case.  This model has no gears and…can't pump a drop.  I hope someone will do an article on how he or she built one that pumps in a future issue of this magazine.  My curse is that I would only consider the oil bath, double back geared design…even though a belt or chain drive is probably more feasible for miniatures.  Boy, I sure wish Aermotor would market one this size…

So, the hub spins around the main shaft on two sealed ball bearings - you can actually turn the wheel by blowing hard on a sail (blade).  I was satisfied with that.  A bigger challenge was the horizontal rotation (pivoting) around the mast pipe.  We simply drilled a hole in the top and bottom curvature of the 4-inch pipe, and welded a steel tube in place and put bronze bushings inside the tube.  This pivot axis is offset just like the real ones to allow it to self-regulate in strong winds. The shaft part of the mast pipe rides inside the bronze bushings, but the challenge was to locate those two holes precisely so the tube was dead true in two axes.  We came very close.  

You can see how nice the lower bronze bushing looks in the completed case.  It wasn't until I finished the furling elements that I discovered there was too much drag to pivot it and had to completely redo the bottom bearing assembly.  I replaced the bushing with a similar type sealed ball bearing that is used on the wheel, but smaller. Finding a suitable bearing with a small enough OD to fit inside the bottom-bearing mount is next to impossible.  (I still don't understand how the Aermotor pivots so easily without using ball bearings - great engineering I suspect.)  Anyway, the bearing is really too big but is difficult to notice with the furling collar, rings, levers, and linkages in the vicinity.  But all the rework was worth it several times over because I can now use a very light vane spring tension and it still pivots clockwise without the tail pulling over.  You veterans know a light spring tension allows it to self-regulate better, requires less force to furl (turn it off) and lets it stay in the wind on those marginally windy days.  I think even La Verne Noyes would approve of the bearing setup.  Fortunately, this thing lives in the city, in a backyard, so the dust and grit that would ruin ball bearings in the country is not an issue.  I'm thankful for that. 

Target practice…

The bonnet (hood or helmet) is a high visibility part (no pun intended) so I spent some time trying to make it look realistic.  A balsa wood frame was made and a layer of fiberglass cloth was resined over it.  Aluminum panels were then epoxied on the sides so I could punch simulated bullet holes through them with an ice pick.  I wanted the ingress and egress effects, which you can't get by simply drilling holes…it worked nicely.  Remember, I'm trying to replicate my brother's and his is shot up pretty badly.  Sadly, the "scars" look like they should be there… 

The tale of the tail…

The tail bones or struts are straightforward - the top one is flat and the bottom is angle iron, both 1/2 in wide and 1/8 thick.  The hardest part was to get the distance between the Z bends in the forward brace correct - it has to be dead on or the front of the bone assembly will either be spread too far apart or not enough to fit properly on the back of the case.  As you know, this brace is also the mount for the vane buffer bolt.  It took me three attempts to get it right.  My vane buffer copies the Aermotor buffer exactly.  A lawnmower valve spring was too stout - I have no idea where the one I'm using came from, but I found it in my spring drawer…pure luck!  It flexes just like it should when it bangs against either side of the case.

The sheet metal vane was cut out with big tin snips and rolled over a 1/8 inch wire frame with a bead roller.  To show you how determined I was to make this exactly scale, the wire frame was made from a 48 inch long piece of steel rod which turned out to be 5/8 of an inch too short.  I could have simply brazed the ends together, but instead, a 5/8 inch piece of rod was brazed between them…too crazy!  Which set the stage for something I had been worried about when I started the project…how am I ever going to faithfully reproduce the "old Chicago Aermotor" logo?  

Thank you, Doyle Herrig!

Doyle has probably sent me over a hundred pictures of his real 8 footer, but two were especially important - straight on shots of the left and right side of an old "Chicago" vane (tail).  Using his photos, I literally hand drew…and erased…and re-drew…and erased…the letters until they were as close as I could get them.  That probably took several hours.  Even harder was to locate them correctly on the vane itself.  For example: on the left side, the "E" and the "R" have to span the curved part of the angle strip reinforcement.  The real kicker is to have the middle part of the "M" positioned so the bolt that goes through the top bone and the vertical support on the right side exits precisely in the "valley" of that "M".  And all the time the spacing between each letter should be equidistant.  The right side has similar challenges, notably the "M" and the "O" have to equally span that vertical support strap.  Lots and lots o' fun! 

OK, so the letters are finally drawn on the poster board.   Now all you have to do is cut them out, one by one.  I used several XACTO blades doing this and my forefinger has taken a permanent set!  Still not done.  So we now have two pieces of poster board in the shape of the vane, with the letters cut out of them.  How do you mask it off so you can airbrush the "weathered red" paint for the letters?  

I love frisket paper!

If I was going to paint directly on the sheet metal almost any masking medium would have worked; however, my "rusty" colored model railroad lacquer was what I was painting over and I didn't want to take the chance of that lifting…especially after all that work!  Art stores sell what is called frisket paper, which is essentially a very low tack vinyl masking sheet.  It comes in various sizes but I used 8-1/2 X 11 since that’s what they had.  I could lay that over the lacquered sheet metal, yet still remove it without lifting the lacquer…whew!  But, I still had to cut out all those letters ONE MORE TIME from the frisket paper before I could airbrush the letters.  It all came out pretty well, but there are probably close to 40 hours just in the weathering and lettering on the tail.  Another one of those high visibility parts of the mill. 

Those tricky furling levers, linkages, collars, rings, ball joints, fulcrum points, moment arms, pivot points, too much throw, not enough throw, too much brake, not enough brake, what angle should the tail fold to, YIKES!  All of these concerns drove me nuts!  Then, you have to cut out the metal pieces, form the metal, and braze or weld the pieces together.  And when you're finished with that, everything has to fit and work in perfect synergy with the other parts.  I guess I "cheated" by making trial pieces out of balsa wood / plywood and repeatedly dry fitting everything until I was satisfied.  Then I cut the pieces apart, traced the outline on steel, and had Big Dave cut them out with his gorgeous plasma torch; but I probably used a straight die grinder with a cut off wheel just as much as the plasma torch to cut out the pieces for the furling elements…as long as you're cutting fairly straight lines, it works fine.  By the way, a Victor #0 welding torch tip is just right for most of the brazing on this.  The best part is the mill turns on and off just like it should and the brake really works!  Again, La Verne must be smiling up there.  

Dang that Doyle…

See, I worked my hiney off to get the tail to fold exactly parallel with the wheel…I thought that's how it was supposed to be.  (I can hear the experts laughing!).  I sent Mr. Herrig an e-mail, bragging about my accomplishment and he quickly taught me that it should only fold to about 85 degrees from the unfurled position…you see, the brake tightens in the direction of normal rotation.  And so there should be some wind pressure on the wheel, even when turned off, to help the brake stay tightly engaged.  So…another week was spent re-doing the furling geometry to meet that 85 degree spec.  It's close, but I'd bet it's closer to 82 degrees than 85 degrees…sorry Doyle.  

No! Not Led Zeppelin…the ladder!  Quandary: do I use the Dempster style (rail and rung) - it's easier…or do I make the loop steps and keep it true Aermotor style?  Ellen (American Windmills) "gently" insisted that the loop style would look better.  I was thinking, "Yeah, but she doesn’t have to form, bend, cut the threads, silver solder all those little swages on them, etc., – and there would be a bunch to do!"  The coup de grace was when she sent me a pair…now I had to commit.  Big Dave simply welded some 3/8 - 16 bolts to a scrap piece of angle iron at the proper spacing to make a wire bending form that worked flawlessly.  He also taught me that with enough heat you can bend the world…heating the 1/8 inch wire to a dull red before bending makes it almost effortless to put those "kinks" in the upper corners of the loops.  A tip: when you run a die over the rod to form the threads and you have to bend the rod right where the threads stop, you will usually fracture the metal at that point.  Yet that is exactly how those loop steps come from Aermotor.  I discovered that simply applying the torch in that area to turn the rod a reddish-orange color, then letting the metal cool SLOWLY will make it quite ductile.  After it cooled, I was able to put a 45 degree bend right at the thread transition point without breaking any of them.  I ended up using 18 loops, each mounts in 5-1/8 inch hole spacing.  The top loop is about 3-1/2 inches down from the oiling platform.  

Cowley makes great coffee…

Let's just say that simply bolting together pieces of angle iron so you end up with a tower-like looking structure isn't going to get it.  Where do you use square headed tower fasteners, round headed, do the nuts go in or out, do the straight angle braces have any particular relationship with the "twisted ones", what goes on the inside - the angle brace or the wire brace, do the pieces overlap on the inside or outside, where does that 45 degree cutout on the oiling platform go, does it matter what leg the lower pull out is in relation to the upper furling yoke handle, what diameter pull out wire should I use, at what angle should the lower pull out handle be when it's turned on, are the angle iron X braces bolted to the bands and/or at the X where they cross, what do the eyelets look like on the end of the wire type braces…and on and on.  Easy stuff for you pros, but for someone who is building one just from pictures and e-mails, it isn't intuitively obvious.  And so for quite a few mornings, ol' Paul and I would have some spirited discussions on stuff to him that was so simple.  He would drink his coffee and try to explain…more coffee…more explaining.  But boy, does he know his stuff!  (Word is, though, that Al Thomerson was his mentor years back…)  If this tower holds up, it's because of their counsel and guidance.   

I welded a 4 inch square piece of 1/8 steel plate to each 18 inch anchor leg and tapped them for a ¼-20 “level adjuster” bolt.  A 2 inch concrete base was poured into each hole so the above bolts could rest on a solid base.  After the concrete hardened, plumbing the tower was just a matter of screwing the bolts in or out…it worked well.  (I used a fence post level and attached it to the mast pipe to make sure the mast pipe was exactly plumb.)  When the two bubbles were centered, the holes were filled with concrete.  The anchors are inside the tower legs and the nuts face out – per Mr. Cowley’s instructions…thanks Paul. 

I was bound and determined to have something more authentic looking than the yard ornament windmills sold at the gardening centers, and I just had to be able to see that old logo on the tail.  It would be standing proudly over a little pump with the pump handle disengaged for hand pumping, but attached to the wooden sucker rod and the wood under the pump would be starting to rot away.  That's the image I had in my mind when I started thinking about putting a small windmill in our back yard over a year ago.  

…the above image would be just a dream.  I know it, and they certainly deserve mention and recognition for their contribution to this attempt.

·        First, to my wife Karen for putting up with my “obsession” with this for over a year.  There are lots of you that could probably do a better job, but just don’t have the time to spend on something like this.  Karen gave me the time.  And to my boys, Jason and Justin, and my daughter, Kimery, who didn’t kick me out of the family because I was always “too busy” for them.

·        “Big Dave” Dyess who taught me how to work with steel and heat.  Never once did he say, “This would be too hard – let’s forget it”.  And for spending so much of his time on this project to help me.  You all should have a friend like him!

·        Bill Cherry for his Website – I got to know the “experts” through this medium and for giving me the opportunity to share my miniature with you.

·        Paul Cowley – taught me how to correctly assemble a tower and set me straight on tower fasteners; and for helping me locate the prototype in the first place. 

·        Doyle Herrig – for taking the time to shoot all those pictures and answer hundreds of e-mail messages – most of which were below elementary to him, I know.  And for sending me all the parts of the furling mechanism, without which I simply couldn’t have built mine. 

·        Ellen Sattler – even at first she was interested in my success and kept encouraging me when I was frustrated.  She also sent me some real parts to model from and convinced me to completely redesign the mastpipe – the furling elements would obviously not work had I kept the original one. Additional construction photos for this miniature can be seen at http://www.windmills.net/jimduda.htm which is part of her website.

  I also got some advice from Ken O’Brock and Randy Stubbs.  Reads like a list of Who’s Who of professionals in the windmill community, doesn’t it?

To me, a rusty, but complete windmill has an aura of stately grace and elegance that somehow invokes a rush of boyhood memories of a simpler time and friendlier place.  I wanted that same feeling when I looked at this and knew that it had to look real to effect those feelings.

If nothing else, maybe someone out there will take the challenge and make theirs look like this but actually pump water into that little bucket, have it overflow and drain back into the pond… I’ll be waiting to see the video of it in this magazine.