Spherical Gear - revolve not working

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MartinCrane
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Joined: Tue Sep 21, 2021 2:30 pm

Spherical Gear - revolve not working

Post by MartinCrane »

Hi:

I'm new to all this, so forgive me if this have been dealt with previously. I'm trying to create a spherical gear with teeth in both axes. I tried multiple methods... first I tried taking a sphere and simply using a subtractive sweep in both axes... but I got basically a blank object... it looked like the algorithm totally failed, the result was a single deformed triangle with the rest of the object being empty.

Then I tried making an additive sweep with teeth in one direction, and another but with inside gears in the other direction with the hope of using a boolian operation to 'cut' the teeth from one object from the other... but that did not work... it failed badly.

Nest I tried an additive sweep in one direction followed by a subtractive sweep in the other, but it refuses to make the shape...

I've tried attaching an image where you can see FreeCAD stubbornly refusing to cut all the teeth, hopefully that works.

Is there a known bug with sweeps? Would anyone know how to make this work?
spheregearfail.PNG
spheregearfail.PNG (128.84 KiB) Viewed 1681 times
Thanks for your time, cheers!
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papyblaise
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Re: Spherical Gear - revolve not working

Post by papyblaise »

what is the use of :?: :?: a waffle mold to place a scoop of ice cream
Attachments
moule à gauffre.PNG
moule à gauffre.PNG (52.5 KiB) Viewed 1637 times
moule à gauffre.FCStd
(523.05 KiB) Downloaded 25 times
MartinCrane
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Re: Spherical Gear - revolve not working

Post by MartinCrane »

Thank you Shalmeneser.

To papyblaise: you seem to believe that if you have no use for it no one else should... What I want to use it for is my business, I wanted to know how to make it, why I wanted to make it does not dictate how/if it can be made. why post such a comment? it is unproductive, you clearly didn't know the answer so why post the comment?
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papyblaise
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Re: Spherical Gear - revolve not working

Post by papyblaise »

this makes the exercise more fun for me, but if it shocks I put them back in my pants (french expressions)
do you prefer "Headbreakers" medieval weapon :lol:
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casse tête.PNG
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domad
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Re: Spherical Gear - revolve not working

Post by domad »

Greetings to the Community!

After a first experiment this is what I managed to get (very similar to the one seen in the video https://i.imgur.com/382WZ0z.gifv), obviously it needs to be improved.
If I have time I will try to model the pinion as well.
For now I cannot attach the FC file because it is "heavy" and raw.
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spherical_gear.gif
spherical_gear.gif (559.9 KiB) Viewed 1387 times
user1234
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Re: Spherical Gear - revolve not working

Post by user1234 »

MartinCrane wrote: Fri Sep 24, 2021 12:49 pm What I want to use it for is my business
How should he help if he does not know for what purpose this part is? You can not make a spherical gear isotrop, so he must know the purpose for the right workflow.

Greetings
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papyblaise
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Re: Spherical Gear - revolve not working

Post by papyblaise »

Do you prefer a boule to play pétanque on the ice floe? :lol:
solution: do the part that subtracts at scale 1.01 so as not to be blocked by the coplanars
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boule a crans.PNG
boule a crans.PNG (56.62 KiB) Viewed 1333 times
MartinCrane
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Re: Spherical Gear - revolve not working

Post by MartinCrane »

To papyblaise:

I was actually thinking of a mechanical eye, the special gear would permit rotation the same way an human eye does.

Cheers!
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papyblaise
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Re: Spherical Gear - revolve not working

Post by papyblaise »

that's a more serious project, with a hemispherical movement
2 simple examples: the movement of video surveillance cameras
or even simpler: the electric mirrors but the movement is very limited
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