I can't figure out how to make the arc i need

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awdang
Posts: 23
Joined: Sat Jul 09, 2016 1:14 pm

I can't figure out how to make the arc i need

Post by awdang »

I'm trying to make a pocket path in an arc shape using the draw arc feature. The arcs I need are not a perfect arc but more of a banana shape. The width of the pocket needs to be 1.75" along the entire path. My problem is that I create the first arc no problem then I make the second arch and it's close to the same radius but not quite. the same. I'm sure I can make them identical using the set radius and set height adjustments but I guess I'm not quite understanding them for example, I draw my first arc then I make an imaginary straight line from end to end. then I measure up from the center of that line to the arc (lets say it's 4"). then I make my start and end points for my 2nd arc 1.75" further out than my first arc and since the height of my first arc was 4", I set the height of my 2nd arc to 5.75" and presto it's not right. I'm using Vcarve pro8.... any help would be appreciated. Thanks Ron

sharkcutup
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Joined: Tue Mar 08, 2016 5:23 pm

Re: I can't figure out how to make the arc i need

Post by sharkcutup »

Have you considered copying the first arc and paste it 1.75" from the first arc?
ZZZ.jpg


Or are you looking at making a different type of arc?

Sharkcutup
V-Carve Pro Tips, Gadget Tips & Videos
YouTube Channel - Sharkcutup CNC
V-Carve Pro 11.554

awdang
Posts: 23
Joined: Sat Jul 09, 2016 1:14 pm

Re: I can't figure out how to make the arc i need

Post by awdang »

that's exactly what i'm looking for and yes I've tried that and it looks kind of like yours. is yours 1.75" the whole distance? or is it some kind of optical illusion. looks wider at the top than bottom like mine does and when I use the measurement tool along the path at various points it either gets wider or smaller. if yours is 1.75" the entire run, then maybe mine was and i'm just looking at it wrong or over or under thinking it. Thanks for your help. I really appreciate it

sharkcutup
Posts: 408
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Re: I can't figure out how to make the arc i need

Post by sharkcutup »

that's exactly what i'm looking for and yes I've tried that and it looks kind of like yours. is yours 1.75" the whole distance? or is it some kind of optical illusion. looks wider at the top than bottom like mine does and when I use the measurement tool along the path at various points it either gets wider or smaller. if yours is 1.75" the entire run, then maybe mine was and i'm just looking at it wrong or over or under thinking it. Thanks for your help. I really appreciate it
Here is another 1.75" arc for I did not save the first one I created. But to answer your question I believe it was an optical illusion due to the type of arc that was created (Sharper curve at top to less gradual curve at bottom). This new one looks more even. But again I'll let you be the judge because you know what you are looking for!!!
ZZZ.jpg
Sharkcutup
V-Carve Pro Tips, Gadget Tips & Videos
YouTube Channel - Sharkcutup CNC
V-Carve Pro 11.554

awdang
Posts: 23
Joined: Sat Jul 09, 2016 1:14 pm

Re: I can't figure out how to make the arc i need

Post by awdang »

Thank you Sharkcutup. Mine does now measure evenly all the way thru. For some reason it plays a trick on my eyes and doesn't seem right. I appreciate the help and if you don't mind another question. Did you manually input arrows and 1.75 between the lines for the visual or is there a way to make the measurement tool do that?
Thanks again! Ron
Attachments
arc.JPG

sharkcutup
Posts: 408
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Re: I can't figure out how to make the arc i need

Post by sharkcutup »

Did you manually input arrows and 1.75 between the lines for the visual or is there a way to make the measurement tool do that?
I used the Dimensions Tool under 'create vector' heading (fourth row second icon) see attached image.
ZZZ.jpg
Just select this icon then select a vector line to measure from and drag mouse from that line to a vector line you want to measure to then click left mouse button. Arrows will then appear between the lines. Now drag the arrowed line to where you want it on the drawing then click mouse button again and the measurement will appear and the line will lock into place where you have dragged it to.

Also I would like to mention here that once the dimensions menu has been chosen if you make a mistake use the undo feature to correct your error. If you try to click on the line to try to just delete it. The dimension process will start all over again creating a dimension line.

Sharkcutup
V-Carve Pro Tips, Gadget Tips & Videos
YouTube Channel - Sharkcutup CNC
V-Carve Pro 11.554

awdang
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Joined: Sat Jul 09, 2016 1:14 pm

Re: I can't figure out how to make the arc i need

Post by awdang »

Well what do you know. There it is. just never clicked on it. Thanks Again!
Ron

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gmm50
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Re: I can't figure out how to make the arc i need

Post by gmm50 »

This is exactly why I have High School students working part time.
I keep reminding them these problems are just like video games. Seems to work.
George

Rando
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Re: I can't figure out how to make the arc i need

Post by Rando »

The trick to remember about creating "parallel" curves is that the effective radius of curves is increased (convex) or decreased (concave) on the two sides. The reason copying the curve looks so odd is that they are identical, and materials with thicknesses don't act that way. If you want a "real" curve like you're asking, you should close the first curve, then use the "offset" command to create the other side, then cut the closed vectors to get the shape you really want. The offset command correctly adjusts the "other" side's curvature. Give that a try :D.

Hope that helps

Thom
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