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You are not logged in. #1 20120313 08:01:50
Need help with circumference and taperLet me start by saying I know absolutely nothing about trig, which I assume I would have to know to figure this out. I'm designing labels that wrap around a flower pot, but cannot figure out how to arrive at what percentage my warp or arc has to be. The pot is 31.5 inches at the top, 27.75 inches at the bottom (circumferences), and the label area will be 7.375 inches high. I have several other pots of varying sizes I'll need to create label wraps for. Is there a particular formula I could use to figure this out? Not sure if you need this, but the opening at the top is 10 inches, and the width across the bottom is 8.5 inches. Thanks so much! #2 20120313 08:35:36
Re: Need help with circumference and taperHi vectorized; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #3 20120313 09:59:26
Re: Need help with circumference and taperhi vectorized, So that tells you how big the radius of the sector has to be. Next, what angle should the sector be? Does this make sense to you? Post back if you want more clarification. Bob You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #4 20120313 10:24:16
Re: Need help with circumference and taperThanks for your responses! Bob, I'm not sure I understand any of that since I never took trig, but I have a fairly decent IQ so perhaps I can figure it out  I'd just need a bit of time. But yes, the diagram you show is what I have but flipped over. When the wrap is flat, it will have a curve and the outer end points will have a slant, which is what I'm trying to find. In Illustrator, I can use the warp tool to create and arc of a specified percentage, so I figure I can use that once I determine the correct formula to do so. #5 20120313 19:53:56
Re: Need help with circumference and taperhi vectorized You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #6 20120314 00:18:00
Re: Need help with circumference and taperBob  I thought I was smart  must be in other subjects. *sigh* I barely even made it through Algebra in high school, but #1 that was about 35 years ago, and #2 I thought it was because I didn't do my homework. Math for the most part is completely over my head. I did try writing down the formula on paper and made notes, to no avail. I hate to ask you to just tell me what it is, but at this point I have to. I'm kind of under the gun on this project, and they're in a hurry, so I need to get a sample of at least one completed today. If you could give me the numbers on this according to my measurements, I'm sure I can follow suit and determine the rest of pots of different sizes. Would you be willing? I'm an artist and make things look pretty. The synapses on the other side of my brain misfire when it comes to math! LOL Last edited by vectorized (20120314 01:02:07) #7 20120314 06:55:10
Re: Need help with circumference and taperhi vectorized, The small circle is the same fraction of the large circle: So these fractions are the same. If that's starting to get confusing, try it with some numbers. Suppose the small circle is 1/3 of the large circle. But the distance Ls has to be one third of L. So Let's say s = 10 inches. If Ls is one third of L, then s must be two thirds of L. So check: If L = 15 and s = 10 then Ls = 5 and 5 is one third of 15 tick. So the formula for calculating L is Now I've done some algebra to get L = something in this equation. Maybe that's too much for you so here it is with those numbers: step 3. So what fraction of the whole circle do we need to make this frustrum? The arc at the bottom is 2 x pi x R1 The whole circle is 2 x pi x L So the angle is this fraction of a whole circle: Now I multiplied that fraction by 360 degrees. If your software wants a percentage then I think you need: Hope that does it. Bob You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #8 20120315 01:08:12
Re: Need help with circumference and taperI think I should be able to work out this formula from here... I may need a bit of assistance from a friend that knows a bit of trig, but this should do it! Thanks so much! #10 20120316 04:48:35
Re: Need help with circumference and taperSo much for that! We can't figure it out... Can you give me the solution in the numbers that I provided? I think if I have that, I might be able to figure out the next one on my own. Another figure you might need is that the label will be .75 from the top of the pot (which is 9.125 high), and the label is 7.375 tall. I need the percentage of arc and the slant. Sorry to be a pest! #11 20120316 06:45:11
Re: Need help with circumference and taperhi vectorized
Oh boy that changes everything! The radius for the label isn't 5.0625 at all because your label isn't at the top! And if I start with a pot height of 9.125 and take off 0.75 that leaves 8.375. But you say the label is 7.375. So is there an inch below the label at the bottom? You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #12 20120316 07:42:02
Re: Need help with circumference and taperYes. The label is 1 inch from the bottom. I noticed, too, that when I create an arc in Illustrator, the ends jut out from the top and it makes it overwrap the pot. I need it to just barely overlap the ends as it wraps. If I try to squeeze it in from the sides, then my artwork distorts. I'm sure I can figure that on my end once I can get the formula down. Yes, I have access to Excel, although I don't know much about it since I work mostly with Adobe Creative Suite programs, being the artsy type. #13 20120316 08:10:23
Re: Need help with circumference and taperI'm trying to include a screen shot of the tool I have to work with in Illustrator, but I can't seem to make it work on this forum. My IQ is dropping as we speak. Help? #14 20120316 10:15:54
Re: Need help with circumference and taperhi You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #15 20120316 10:35:08
Re: Need help with circumference and taperI have the screen shot (I'm on a Mac), but I can't get it to post here in my reply. I did as you suggest, but it won't show... #16 20120316 10:39:50
Re: Need help with circumference and taperOh I see now! I have to have at least 10 posts to be able to upload an image with my reply. This makes #10. I'll try in my next post! #17 20120316 10:44:02
Re: Need help with circumference and taperNever mind. I just tried again. It's just not working. I go to image upload, select one slot for image, select the image on my hard drive, click preview and nothing. #18 20120316 11:16:50
Re: Need help with circumference and taperhi You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #19 20120316 22:25:28
Re: Need help with circumference and taperThanks so much! Will try this today. #20 20120316 22:29:58
Re: Need help with circumference and taperHow funny... worked that time! Kinda wish I had a CAD program now... #21 20120316 22:51:37
Re: Need help with circumference and taperOK I can see your picture with 12%. You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei 