"Weight" center of an irregular shaped object??
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- Vectric Craftsman
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"Weight" center of an irregular shaped object??
I have a long irregular shaped object that I would like to hang on a string in a balanced way. . If I center it, its length from the origin center to either side would be equal, but one side is actually "fatter" than the other. So If I use that origin as center and try and hang it, it will slant down on the heavier side. Is there any way I can determine the center of this shape so that the weight (not length) on either side would be equal? The wood is 1/8 inch plywood with uniform density throughout.
Thanks
K
Thanks
K
- dwilli9013
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Re: "Weight" center of an irregular shaped object??
Well a really trick way I have seen to do this is put the object on edge then place a dowel rod or other round object under the edge approximately where you feel the center may be. Then roll you object back and forth until you find the balance point. Once you have gotten close pencil mark you center point and hang. This obviously is no good if you have no flat edges on your frame.
D-Dub
Dwayne
Dwilli
Dwayne
Dwilli
- Jim_in_PA
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Re: "Weight" center of an irregular shaped object??
Honestly, the easiest way to calculate this is to cut a sample with a bunch of test holes that you can hang and experiment to find the best balance point...and then finalize your tool path to cut the mounting hole in "the spot".
- scottp55
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Re: "Weight" center of an irregular shaped object??
Pad smallest suitable clamp, put a piece of cord around clamp in center, and move clamp until it hangs right....mark!
I've learned my lesson well. You can't please everyone,so you have to please yourself
R.N.
R.N.
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Re: "Weight" center of an irregular shaped object??
Wasn't there a gadget at one time that would find the centre of mass? Or I might be dreaming. Autocad?
- Rcnewcomb
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Re: "Weight" center of an irregular shaped object??
Here are the steps using AutoCAD: ->Link
- Randall Newcomb
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10 fingers in, 10 fingers out, another good day in the shop
- adze_cnc
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Re: "Weight" center of an irregular shaped object??
If you already have the object: https://youtu.be/HaaL2wucyRE
- mtylerfl
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Re: "Weight" center of an irregular shaped object??
There used to be shortcut keys for calculating volume for 3D models, but was removed. Anyway, I don’t think that would have helped for determining Center of Mass.tomgardiner wrote:Wasn't there a gadget at one time that would find the centre of mass? Or I might be dreaming. Autocad?
An old-school method for finding Center of Mass for planar shapes/objects was to make a cutout version in card stock and balance it or hang it from a string.
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- Vectric Apprentice
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Re: "Weight" center of an irregular shaped object??
If you are willing to uploade your shape, I can try to find the c.o.g. using a cad software.
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- Vectric Craftsman
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Re: "Weight" center of an irregular shaped object??
The Balance gadget might be of use to you.
http://forum.vectric.com/viewtopic.php? ... et#p194186
http://forum.vectric.com/viewtopic.php? ... et#p194186
- SteveNelson46
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Re: "Weight" center of an irregular shaped object??
Why not just clamp something relatively sharp or round in a vise (back of a knife, steel rod...) and just hand balance it on the rod or knife. Make a mark on the edge then rotate it 180 degrees and hand balance it again. Draw a line between the two marks. That is your horizontal center of balance.
Steve
- mtylerfl
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Re: "Weight" center of an irregular shaped object??
I stand corrected! There still is a set of shortcut keys for calculating the volume of 3D models (they were changed sometime in 2012)mtylerfl wrote:There used to be shortcut keys for calculating volume for 3D models, but was removed...
Here is the shortcut combo: CTRL-ALT-SHIFT-V
This may not help with determining Center of Mass, but I wanted to post the correction to my previous statement. (Volume calculation can be handy for folks making molds for glass, chocolate, wax, etc. so they can get a close estimate of material needed for pouring into the molds.)
Michael Tyler
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