Hey Guys
I'm starting to build a homemade windmill with about a 4' wheel. I want it to look somewhat like the typical Aermotor windmills. I'm pretty good cutting and welding steel - so I'm making it out of steel. I'm using a car front hub bearing for the hub bearing - the type where the mounting flange and wheel flange are both pressed onto a single bearing to make a complete unit. These are very strong and pretty cheap if you search a little. Mine was $25. When I started on this - I just assumed that since these windmills have been around since the civil war - there would be detailed drawings for every part all over the internet. To my amazement - so far I've found nothing. If there is a website with detailed drawings out there - please let me know the URL. Otherwise I'd like to get some dimensions on the wheel as that is the part I'm fabricating first. I would greatly appreciate the following dimensions from a vintage windmill - a 6 foot one if possible as that's closest to my plan. I'll just scale it to my size.
Wheel outer diameter
Length of sails
Width of outer side of the sail
Width of inner side of the sail
Assuming the sail has a radius - with the sail laying flat, height on the curvature
Angle of the blade on the wheel - measured as straight line between blade edges
Gage of steel for the blades
Rod diameter of the spokes
Thanks in advance. I'll post pics of progress once I get into the construction
Tom
Building a home windmill
Re: Building a home windmill
Hey Tom. Welcome! it's very interesting to see what you design. I have designed ,legally protected, and made a wheel for 6 and 8 ft mills that is completely reversable, interchangable, and completely resizable for most 6 and 8 ft 5- spoke wheeled mills. Also, I have designed and built a prototype of a self -oiling windmill for a convertable 6- or 8 ft size, using mostly common parts a person can get at a hardware store. Yes, I know fellows. But it's not like a PARISH. All enclosed, self oiling, changable stroke etc.
Anyway, was about done making all the fixtures and jigs for the wheel, when "life" got in the way. HAve not done much since. Oh well, staring the age of 70 in the face, I have plenty of time left, right?
I would encourage you to research the physics of a windmill, and dynamics of the wind effects, how wear patterns affect things, and other mechanical forces in the windmill itself work, and affect things. For instance, thrust, dynamic action, end play, stresses, and other things. Which direction will it rotate? How will it oil? direct stroke or geared?
You might pick up a c opy of A FIELD GUIDE TO AMERICAN WINDMILLS by T Lindsay Baker. This will give you a great start on understanding. Also check out the library section here. Lots of info there.
Anyway, was about done making all the fixtures and jigs for the wheel, when "life" got in the way. HAve not done much since. Oh well, staring the age of 70 in the face, I have plenty of time left, right?
I would encourage you to research the physics of a windmill, and dynamics of the wind effects, how wear patterns affect things, and other mechanical forces in the windmill itself work, and affect things. For instance, thrust, dynamic action, end play, stresses, and other things. Which direction will it rotate? How will it oil? direct stroke or geared?
You might pick up a c opy of A FIELD GUIDE TO AMERICAN WINDMILLS by T Lindsay Baker. This will give you a great start on understanding. Also check out the library section here. Lots of info there.
Call Dan Benjamin for parts. P M me for the phone number.
Re: Building a home windmill
Hey
Thanks for quick informative reply. The project I have in mind does not actually do anything work - at least initially. By using a vehicle hub - I have nothing to oil, no end play, extremely high load bearing, and a unit built for extreme environments (at least from the viewpoint of a windmill). This is a project just for the enjoyment of building something. By scaling an existing design - I'm hoping to avoid as much as possible the design issues. I'd prefer not to reinvent the wheel - as I'm building a simpler wheel than what's already available from Aermotor, Dempster, and so on. So - I'm just looking for a few dimensions to get started. My backup plan is to scale things as much as possible from pictures on the internet. Thanks again for reply
Tom
Thanks for quick informative reply. The project I have in mind does not actually do anything work - at least initially. By using a vehicle hub - I have nothing to oil, no end play, extremely high load bearing, and a unit built for extreme environments (at least from the viewpoint of a windmill). This is a project just for the enjoyment of building something. By scaling an existing design - I'm hoping to avoid as much as possible the design issues. I'd prefer not to reinvent the wheel - as I'm building a simpler wheel than what's already available from Aermotor, Dempster, and so on. So - I'm just looking for a few dimensions to get started. My backup plan is to scale things as much as possible from pictures on the internet. Thanks again for reply
Tom
Re: Building a home windmill
Ok, so you just want a wheel that spins, and nothing else I guess. I use 20 ga galvanized sheet for the sails. 1 inch X 1/8 inch for rails and arms. What holds sails to rails are your choice. You might need something to keep it guided into the wind. On the other hand, if you guide it into the wind, you need something to automatically turn it OUT of the wind also. The reasons for this is that it doesn't fly apart and become shrapnel in high winds. These are considerations for putting something into the wind, up in the air. So, it needs to rotate into or out of the wind, and be able to be shut off. from the ground. And you thought this was going to be simple? LOL
Call Dan Benjamin for parts. P M me for the phone number.
Re: Building a home windmill
Oh, sails for an average 6 ft wheel are about 24 in long, and about 5 or 6 inches wide at the base, and about 10 at the top end. If you don't want to taper them, you don't have to. 10 in wide all the way is ok. Then there is the matter of straight or rolled, or curved. Keep it all balanced within a couple ounces, and use locking hardware all around.
Now, the tail is another matter. If you don't use one, then give it a wide berth as you walk around it on a breezy day.
Now, the tail is another matter. If you don't use one, then give it a wide berth as you walk around it on a breezy day.
Call Dan Benjamin for parts. P M me for the phone number.
Re: Building a home windmill
Hey
Thanks guys ! This will get me started. I guess I should have defined the goal a little more. I plan to install a tail - off center from the wheel with a spring to center (similar to Aeromotor). I'll most likely have provision to manually get the tail perpendicular to the wheel. I plan to balance and true the wheel as close as possible (I do this with bicycle wheels regularly).
Tom
Thanks guys ! This will get me started. I guess I should have defined the goal a little more. I plan to install a tail - off center from the wheel with a spring to center (similar to Aeromotor). I'll most likely have provision to manually get the tail perpendicular to the wheel. I plan to balance and true the wheel as close as possible (I do this with bicycle wheels regularly).
Tom
Re: Building a home windmill
Those dimensions you guys supplied are in the range I was expecting except for the sail material. I would have guessed 16 ga minimum - possibly even 16 or 14 ga.
Can you give me some idea as to to the angle for the sails and any recommendation on straight vs curved sails. If curved - what arc height for your width sail (at top of sail) - or just the radius if you have that?
Tom
Can you give me some idea as to to the angle for the sails and any recommendation on straight vs curved sails. If curved - what arc height for your width sail (at top of sail) - or just the radius if you have that?
Tom
Re: Building a home windmill
Some makers actually had straight sails. But if you wish to roll them, it won't take much. I don't have a measurement. Offhand, I would guess that a curved sail for you would be maybe an inch less than the flat measurement. (point to point)
If the wheel turns CW (from the front) then also from the front, the vane (tail) needs to swing to the right. Yes it needs to be off center to the mainshaft. which way I forget. AERMOTORS turn cw so check a diagram to see how the tail is offset from the mainshaft line.
Opposite for the mill turning CCW.
If the sails are not rolled, then a thicker gauge will be needed, as a rolled sail incorporates strength, so 20 Ga is good for 6 and 8 ft mills mostly.
If the wheel turns CW (from the front) then also from the front, the vane (tail) needs to swing to the right. Yes it needs to be off center to the mainshaft. which way I forget. AERMOTORS turn cw so check a diagram to see how the tail is offset from the mainshaft line.
Opposite for the mill turning CCW.
If the sails are not rolled, then a thicker gauge will be needed, as a rolled sail incorporates strength, so 20 Ga is good for 6 and 8 ft mills mostly.
Call Dan Benjamin for parts. P M me for the phone number.
Re: Building a home windmill
Here's a diagram of an Aermotor case. The tail pin is offset from the mainshaft for the wheel to the left ( from the front) a couple inches.
Also a picture here of the wheel and sails. You can guess at a curve, and get it right.
Also a picture here of the wheel and sails. You can guess at a curve, and get it right.
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Call Dan Benjamin for parts. P M me for the phone number.
Re: Building a home windmill
Makes me want an Iron Man Z702 (4’) mill?
