Mechanical Engineer question... or question for anyone that's had basic geometery.
If you are asking will the blue pins represented by the distance A ever get longer, than no, assuming the ride in the same plane as the pivot pin does.
If you are looking for clearance for the supporting side member to fold, then yes, as it does not ride in the same plane as the pivot, you would need to draw a circle starting at the pivot, and touching the lower point of the member, you can see that for it to clear, it will pivot outward somewhat until it reaches the same plane as the pivot pin, that is the point of maximum length.
If you are looking for clearance for the supporting side member to fold, then yes, as it does not ride in the same plane as the pivot, you would need to draw a circle starting at the pivot, and touching the lower point of the member, you can see that for it to clear, it will pivot outward somewhat until it reaches the same plane as the pivot pin, that is the point of maximum length.
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I made the parts in Solidworks and confirmed my thoughts before answering but then I made the blue holes and the hinge at the same centerline for lack of a better sketch.
My answer is therefore correct until better dimensions and complete dimensions are given.
Since the biggest diameter circle with the circumference going thu the blue hole to the right and it's center on the blue hole to the left, the arc obtained by drawing a radius arc from the hinge centerpoint and intersection the circuference therof on the center of the right most blue hole will result in movement only within the larger diameter.
Simple huh?
My answer is therefore correct until better dimensions and complete dimensions are given.
Since the biggest diameter circle with the circumference going thu the blue hole to the right and it's center on the blue hole to the left, the arc obtained by drawing a radius arc from the hinge centerpoint and intersection the circuference therof on the center of the right most blue hole will result in movement only within the larger diameter.
Simple huh?
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Well, simple math in my world but I'll say no based on your first drawing. If the hinge were on the top, the overlap of part 2 past the end of part 1, when folded flat on top of each other, would be equivalent to the gap between the two parts while in the flat position. Based on the second picture, with the hinge 2 inches down from the top of part 1, I would think part 2 could not overlap the end of part 1 when folded because of the interference of the two parts on each other.
Just an observation after the fact but I don't believe you'll ever have to worry about the overlap since the joint isn't likely to rotate, all the holes are oval.
Just an observation after the fact but I don't believe you'll ever have to worry about the overlap since the joint isn't likely to rotate, all the holes are oval.
If the blue dots are below the point of the hinge, it will get longer til the three points fall upon the same line, at whcih time they should return to their original length, and possibly a little shorter.
At 1/4" The amount may be negligible.
If you want to test it, make the offset of the blue dots to the hinge pin larger, and build some sort of model out of cardboard, paper, etc.
At 1/4" The amount may be negligible.
If you want to test it, make the offset of the blue dots to the hinge pin larger, and build some sort of model out of cardboard, paper, etc.
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This is the 5th time I've tried to post this!


YES, the length DOES get longer, mainly because of the pivot of all 3 points aren't in perfect alignment.
However, the inch or so that it lengthens doesn't affect it so much that it won't work.
An over-view of what this is all about:
There is a chain that goes around the 2 blue 'holes' in the diagram and the hinge allows the shorter arm to fold onto the top of the longer one to allow for an over-all narrower width for transport. The chain gets slightly tighter as the arm is folded from the flat position to the folded position, but because of the slack in the chain, it doesn't bind up.
Thanks to all of you that answered!

This is the 5th time I've tried to post this!



YES, the length DOES get longer, mainly because of the pivot of all 3 points aren't in perfect alignment.
However, the inch or so that it lengthens doesn't affect it so much that it won't work.
An over-view of what this is all about:
There is a chain that goes around the 2 blue 'holes' in the diagram and the hinge allows the shorter arm to fold onto the top of the longer one to allow for an over-all narrower width for transport. The chain gets slightly tighter as the arm is folded from the flat position to the folded position, but because of the slack in the chain, it doesn't bind up.
Thanks to all of you that answered!
DTR's Volcano Monitor, Toilet Smuggler, Taser tester, Meteorite enumerator, Quill counter, Match hoarder, Panic Dance Choreographer, Bet losing shrew murderer
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From: Kenai Alaska
It was interesting but also gave me a nosebleed. So it was both fun and painful. Sort of like getting spanked.
Rats, I made it creepy again didn't I.
Rats, I made it creepy again didn't I.
DTR's Volcano Monitor, Toilet Smuggler, Taser tester, Meteorite enumerator, Quill counter, Match hoarder, Panic Dance Choreographer, Bet losing shrew murderer
Joined: May 2007
Posts: 965
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From: Kenai Alaska
That thing is huge! Nice work but I think you should paint it pink.
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