Creating pattern using background image as reference

[Garage5C6B]

Hello,

I've been at this for a few hours trying to figure it out. Essentially I'm trying to clean up a graphic for a user panel for a tire machine that isn't produced anymore. The image below is a sample of 3 similar circle shapes and the hashmarks surround a physical dial. I'm trying to recreate the hashmarks that go all around the circle (which will then be overlaid onto a solid black background) but I am having very annoying issues. I'm positive that it's my lack of knowledge of the program and am hoping for help!

Here are my issues:

1) I've been youtubing this and have run across blending, as well as using the rotate feature. The one that seems to be the easist for me is the rotate feature, however, I can't locate the center of the circle that I draw! I can't get it to snap to the center of the circe to get the proper reference to then rotate against.

2) I CAN get the proper center of the circle reference if I CTRL-Y, however, the back of the image (the reference circle with hashmarks) disappears and a white overlay is there which is no help at all since in some of the images, the hashmarks are not perfectly spaced so I might have to do some individual copies rather than a full pattern at once. 

In summary, I need to draw the hashmarks and then rotate them around the circle all while being able to see the background image as a reference so I can size it appropriately.

Here is the image:

Other methods are appreciated! But please, be as detailed as possible with how to complete the steps.

Thank you!

[SJRiegel]

I worked on this, and came up with a solution - it's not fast, but it works reasonably well. Start with a corcle inside the base of the hash marks, then make a single point with the pen tool. Center those on each other, with the circle as the key object, then lock the circle. 

Make sure that Use Preview Bounds in unchecked in your preferences. Draw your first vertical line at the top of the guage, using the shift key to make sure it's straight. Select the line and the point and group them. (this gives you a bottom point of your group to rotate around)

Use the Transform Effect twice on this group. The first one makes have of the long hash tags, the second reflects them. 

Repeat for each size of hash mark.  

EDIT: I got better results on the Reflect transformation when I reduced the line weight to .25 pt. After the effects are to your liking for position, you could use Expand Appearance to make the effect into separate lines, and then increase the line weight as needed.

[Jacob Bugge]

Garage,

"I'm positive that it's my lack of knowledge of the program and am hoping for help!"

This intriguing case goes deeper than that.

A crucial part of what you are facing is the fact that such a good old user panel (usually) has some inbuilt inaccuracies/strangenesses, but this one is also quite regular/accurate.

As in most cases, I believe you need to create a working panel in a managable way which means that you need to make it more regular/accurate than the original while retaining the way way the hash marks fit the dial so it works the same.

Most significant for the purpose of reconstruction are the following properties:

A) The inaccuracy that most of the hash marks are misaligned with the actual centre (of the actual dial), in a both regular and irregular way, and that applies to both direction and distance;

B) A high degree of accuracy of the hash mark increments;

C) The irregularity that the start at 2 and the end at 10 are apart by a distance/degree that differs from that of a whole number of hash marks;

D) The irregularity that the whole set is slightly rotated clockwise.

This means that certain steps are needed, and it gives you certain opportunities of a managable recreation.

You can, Smart Guides being your friends, and always keep copies of the artwork at crucial stages in the process so you have something to fall back on, and you can compare the new and original artwork to make sure that you have a satisfactory match:

1) Establish the centre of the hole/actual dial, then create the best possible fit of a circle round it corresponding to the inner ends of the has marks, some being inside the circle, others will be outside; this addresses the first part of A); this can be done with a circle that fits the hole in the image, remember to have the centre shown; copy the circle and hide the original;

2) Establish the distance/angle between the hash marks at 2 and 10 by ClickDragging with the Line Segment Tool from the centre to best fits with the hash marks on the image; this addresses C) and D), use the outer ends of those hash marks, then adjust the lengths of the lines to be identical, still starting at the centre, then lock the lines;

3) Cut the copy circle from 1) at the intersections with the lines from 2) and create at least two copies;

4) For each of the hash marks at 2 and 10, ClickDrag with the Line Segment Tool from the intersection between the line from 2) and the (end of the) copy circle created in 3) to the end of the line; this will give you hash marks of identical lengths;

Now you are able to create the full set of all the longest hash marks as a Blend as follows:

5) Create a vertical line with the same length as the hash mark at 2/10 and the same/desired Stroke Weight, then with the Selection Tool Alt/OptionClickDrag (an inner copy of) the line by the upper end to snap to the lower end, then set the Stroke of the lower/inner copy to None and Group it with the upper line/actual hash mark;

6) With the Selection Tool Alt/OptionShiftClickDrag (a copy of) the Group from 5) to the right (horizontally) by a suitable distance; create copies of both lines;

7) Set the Blend Options to Specified Steps = 7 and Align to Path, and Make the Blend;

8) Select the Blend from 6) and the topmost copy of the cut circle from 3) and Replace Spine;

Now you have the full set of all the longest hash marks round the (copy) circle, and you can create the full sets of all the intermediary and shortest hash marks as follows, just on top of the longest ones:

9) Establish the length of the next shorter set of hash marks as in 4), then shorten the length of the copies from 6) and repeat 7) and 8), only with Specified Steps = 39 for the intermediary length (intermediary hash marks at 2/4/6/8) and with Specified Steps = 79 for the shortest length (unmarked hash marks);

Now you have all the full sets of all the hash marks, and you can add the numbers as follows:

10) Use a best possible representation of the font and sizes original numbers and place them for best fit; you can create a circle through the centres of each size of letters and create Blends with dots similar to those made in 7/8 and 9 for the two sizes, and use those dots as guides to place the numbers; all numbers are unrotated;

11) Hide the bits that are unwanted in the final artwork, notably the cut circles. In that connexion, you can, if you wish/must, expand the Blends and delete the shorter hash marks that are on top of longer ones, and/or reverse the stacking order of the hash mark set.

Edit: Hi Susan, working for a while on a different approach before seeing yours.

[SJRiegel]

Hi Jacob - as always, there are multiple approaches to these problems. I love the challenge of figuring out how to make it happen.

[Garage5C6B]

I've been away on vacation / busy at work so have not had a chance to finish. I'll be working on it soon but thank you both for your responses! I'll be getting back at this soon!

[Jacob Bugge]

So far three of us; and thank you for the intriguing challenge, Garage. We shall look forward to the next one.

[kphotopage]

Garage. Hi.

Here I created 2 Pattern Brushes.

I applied one brush to the right side of a cut circle.

Then again, applied the other brush to the left side of a cut circle.

K