ceiling fan blade balance - the blade weights go where?

have a _very_ old emerson 32" six bladed ceiling fan. very similar to 'hunter original' in motor construction, but I'd guess mine is a 1920
vintage, + or - a hair. I'm doing a restoration on it of sorts, & planning on using it starting tomorrow.
few days ago I weighed all the blades (with their cast iron 'motor blade fastener arms' attached) on my triple beam, and then made weights from an old unknown alloy solder so that the blades (with their attached 'arms', as a unit) will be within 1/4 gram of ea other* (once the weightsd are attached), BUT, where exactly to fasten the weights? seems the logical places -might- be:
a. as close as possible to motor arbor, on upper surface of blade, centered leading to trailing edges,
or maybe
b. centered halfway between between upper outer edge-center of each cast iron 'blade arm' and extreme outer tip of each blade, and centered halfway leading edge to trailing edge?
or, would some kind soul please tell me the 'standard procedure'?
thanks in advance :-)
*this procedure, making the weights and 'fine tuning' them took 'some considerable hours', not counting the other hours in remaking blades themselves, with three coats hand rubbed, fabricating the ceiling hanger hook, etc etc ;-)
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The best way I've found is to balance two blades at a time. Put on two that look close and try the fan. If it runs true, mark those as a pair and try another two. The problem with weighing is that, even if identical, if the weight is not distributed evenly, they will wobble. Once you get three balanced pairs, put them all on. I have taped pennies or nickles on the top of a blade to do it. From the wobble deflection of a pair, guess a weight and try moving it in or out. Less weight out equals more weight in. The main thing is to do the blades in pairs, not all at once. I'm sure you're aware but the heavy blade will be on the outside of the wobble circle. Weight the other one. Respectfully, Ron Moore
dave wrote:

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dave wrote: (clip) BUT, where exactly to fasten the weights? (clip) ^^^^^^^^^^^^ This is another idea that ought to work: The heaviest blade is going to be used with no added weight. Balance it across a support, to find out where its center of gravity is. Then place each weight on its corresponding blade so the balance point is the same distance from the end. You will end up with all blades having the center of gravity at the same radius. That should do it.
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On Mon, 12 Jul 2004 04:46:23 GMT, "Leo Lichtman"

Or simply put it all together, put on a longer hanger pipe and lay it on saw horses with the blades vertical and balance it like a tire.
Which is what I did before I put mine up.
Works fine for me.
Gunner
That rifle hanging on the wall of the working-class flat or labourer's cottage is the symbol of democracy. It is our job to see that it stays there.         - George Orwell
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wrote:

Now that's a good idea ! I've never been able to figure out that problem on the ceiling. And I've tried about everything short of a strobe.
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dave wrote: (clip) BUT, where exactly to fasten the weights? (clip) ^^^^^^^^^^^^ This is another idea that ought to work: The heaviest blade is going to be used with no added weight. Balance it across a support, to find out where its center of gravity is. Then place each weight on its corresponding blade so the balance point is the same distance from the end. You will end up with all blades having the center of gravity at the same radius. That should do it.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ I can vouch that this method will work as I have done it. I achieved a nice balance at all 3 speeds with a chandelier suspended below the fan. There is only a small shimmy in the dangly things at high speed probably due to twisted blades whose pitch angles I couldn't balance well enough.
Two additional things to check:
Tips of blades equally spaced around perimeter circle
Pitch angles all equal. If not, or if blades are twisted along their length try to correct or match opposite pairs
Hope this helps, John.
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dave wrote:

Unfortunately, because of uneven weight distribution (I'm assuming plywood blades) weighing them doesn't work. My technique is to put the fan on it's side, and if the bearings are decent the heavy blade will turn to the bottom. Add steel washers about 3/4 of the way out on the opposite blade until you can't get the blades to turn at all, no matter what position you start them in. This will get you real close. Moving the weight inward will help if the weighted blade is too heavy. Moving it farther out will help if it is just a little too light.
When you get as close as you can get with static balancing, then put it in place and run it. Move the washer(s) in and out a bit to make final adjustments. 1" OD steel washers and 2" packing tape seem to work well. Make sure the blade is real clean before applying the tape, as you don't want the tape to come loose and let those washers fly!
Jon
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"Jon Elson" wrote: (clip) My technique is to put the fan on it's side, and if the bearings are decent the heavy blade will turn to the bottom. (clip) ^^^^^^^^^^^^^^ You have reminded me of a technique which I found useful once. If you have a vibrating engraver, hold it against the fan, and this will make the bearings drift smoothly until the heavy side is down.
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dave wrote:

Since you're doing it by total weight, put your added weight at the balance point of the blade. You want them all to have the same balance point too.
Balance them out first, then weight them as needed.
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I used a trial and error method. I used "sticky tack" for weight. Sticky tack is used to hold posters on the wall without sticking a pin in the wall.
The nice thing about sticky tack is that it won't hurt someone if it comes off and it is easy to move and change the amount.
chuck
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calmly ranted:

I put them centered between leading and trailing edges on the top just outside the diameter of the outer bolt.
I would be willing to bet that bent arms are the #1 reason for wobbly fans. It happens when the kids (or Mom when cleaning) put broom handles into them while they're spinning, while they're stored, and when they're dropped during installation or repainting, etc.
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