(solved)circular problems

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Solo318i
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Posts: 34
Joined: Tue Apr 13, 2021 2:54 pm

(solved)circular problems

Post by Solo318i » Mon Apr 26, 2021 2:31 am

Is there a tool that can tell me the circumference of a circle? I have tried to use the measurements tool for an arc, but it says my circle is not an arc and wont measure it. It seems ridiculous to have to break out a calculator to do math for a CAD program.
Last edited by Solo318i on Sun May 16, 2021 8:31 pm, edited 2 times in total.

Solo318i
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Posts: 34
Joined: Tue Apr 13, 2021 2:54 pm

Re: circumference of a circle

Post by Solo318i » Mon Apr 26, 2021 2:44 am

trigger wheel.dxf
(113.81 KiB) Downloaded 313 times
This is what I'm playing with. I have figured out how to measure half of the circle. But I have to do it before I do anything else to the circle?

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Husky
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Re: circumference of a circle

Post by Husky » Mon Apr 26, 2021 2:55 am

Solo318i wrote:
Mon Apr 26, 2021 2:31 am
Is there a tool that can tell me the circumference of a circle?
Select the circle and check the Property Editor for the circumference.

Solo318i wrote:
Mon Apr 26, 2021 2:44 am
trigger wheel.dxf
This is what I'm playing with.
Is it part of the game to have 19 stacked circles ...?
Work smart, not hard: QCad Pro
Win10/64, QcadPro, QcadCam version: Current.
If a thread is considered as "solved" please change the title of the first post to "[solved] Title..."

Solo318i
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Joined: Tue Apr 13, 2021 2:54 pm

Re: circumference of a circle

Post by Solo318i » Mon Apr 26, 2021 3:02 am

Now that I can measure the circumference, I divided that by 74 (to get 36 teeth of equal size). I drew a square defined by that size and attached it to the circle. Did a rotate and multiple copy 36 times at 10 degrees each. Now I can't break out the segments to make the "teeth".
triggertake2.dxf
(293.77 KiB) Downloaded 297 times
Any suggestions would be welcome. (now that I have wandered off the original topic)

Solo318i
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Posts: 34
Joined: Tue Apr 13, 2021 2:54 pm

Re: circular problems

Post by Solo318i » Mon Apr 26, 2021 3:35 am

I did it a different way. I had to start over though.
I overlayed the "tooth" and took out the unwanted segments prior to the rotate and copy. That let me break out the rest of the "teeth".
I'm really working hard to expand my understanding of the software. Is there a way to "fix" the original file? Here is a copy of the "successful" file.
trigger wheel 36-1.dxf
(128.96 KiB) Downloaded 299 times
As I stated, this should do the trick, but I would like to know how to correct the first attempt with out having to go back and start over. :|
I hate just throwing away the time I spend "messing it up"

CVH
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Re: circular problems

Post by CVH » Mon Apr 26, 2021 4:43 am

hi,
If you need 36 teeth 50% ON - 50% OFF
Then ON + OFF = 360/36 =10° & ON = OFF = 5° or 360/72 (not 74 :wink: )

From your attempts I understand that the outer diameter is 4".
But then it gets unclear ... and I don't understand the squared out gap.
At the bottom of the teeth you won't have 50/50 ...

I drew a outer circle R=2" (CR)
An angled line 2.5 long at 0°(LA)
An angled line 2.5 long at 5°(LA)
An angled line 2.5 long at 10°(LA)
An auxiliary circle with R = the length of the chord at the outer circle (CI)
An inner circle through the new intersection (CI)
---
Removed the auxiliary circle
---
Auto trimmed the angled lines (AX) between the circles
---
Auto trimmed the circles (AX) between the angled lines
---
Removed the 10° line
---
What was left, I rotated (RO) around the center, copied (36-1)=35 times, angled 10°
myTriggerWheel.dxf
(130.27 KiB) Downloaded 302 times
No hard math involved. :P

BTW: The circumference is an endless number = 2Pi x 2" = 12.566370614359172953850573533118....
The number QCAD displays is rounded.

Regards,
CVH

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