What's happening in that knurl demo video? (Sept. 30, 2015)

hansrudolf

Dear community,
I'm trying to analyze and re-create what is done in that video. But as hard as I try, I come to a hard stop. I will try to describe what I see. The task is to generate a knurl pattern on a cylindrical surface. What happens in the first minute is quite clear, a 180 deg. helix is drawn and then a perpendicular plane defined at the endpoint of that helix. Then we see that a rectangle is drawn in the free area (with the rectangle tool). Now we see about 20 seconds of frantic mouse movements, selecting and unselecting sides and corners of the rectangle, the mouse pointer moving to the 'normal' and then to the 'pierce' icon (not sure if both are clicked or just accidental movement), and the upper roght corner of the rectangle is hanging at the end of the helix. Now something happens that I absolutely don't understand: the rectangle makes a 90 deg. clockwise turn. I made several experimental drawings, trying to rotate a rectangle, but failed completely.

So I hope someone has seen that video also (I'm not sure how to find the videos from the e-mails, they are not in the tutorials...) and can tell me exactly how all that above functions and how I can rotate a rectangle without deleting all its constraints.

Regards, Hansrudolf

nav

Hi @hansrudolf in both Cody`s knurl video and my post video we use center point rectangle, in the video below I constrained a point of both your sketches and I`m able to rotate them.

cody_armstrong

@hansrudolf The selecting of sides and corners of the rectangle is to delete the horizontal constraint that all rectangles have.  You will not be able to rotate a rectangle until these constraints have been deleted.  In that example it is a diamond knurl. Sketching a rectangle, deleting the constraint, and rotating the rectangle is a fast way to create a diamond shape. However, you can simply sketch the diamond shape with lines if that is what you are comfortable with.


Here is an example Knurl if you would like to take a look at the sketches and features.

hansrudolf

Many thanks for your answer, unfortunately it's not so easy in my case. Selecting and unselecting sides and corners of the rectangle do not remove any constraint. After consulting the help index I found that by selecting the hor. constraint (after making all visible) and using the delete key I can remove it. But even after doing that the rectangle does not rotate; I can only make it larger or smaller. It stays horizontal all the way. Something I must do terribly wrong? The remaining constraints are parallel, perpendicular and coincident. Do I have to remove these also?

Regards, Hansrudolf

nav

Hi @hansrudolf hope this helps.

hansrudolf

Unfortunately, no. I appreciate the big work, but I can't reproduce it. Such a video is much too fast to see what happens, and as I wrote before, even if I delete the horizontal constraint I can't rotate the rectangle.

Kind regards, Hansrudolf

cody_armstrong

@hansrudolf Instead of using a rectangle, have you tried sketching four lines in a diamond shape and making them perpendicular?  This accomplishes the same thing.

It's difficult to tell without looking at your actual sketch which constraints are keeping your rectangle from rotating. Deleting constraints doesnt hurt, so I would delete them one at a time until I found the one that wasnt allowing me to rotate.  

If you would like us to take a closer look, consider making the model public and posting a link here.

hansrudolf

Sure, if I draw a rectangle from 4 individual lines, I can arrange it in any position. My feeling now is that I don't know thr right mouse click/movement or whatever to rotate a rectangle. I've drawn a public example, two rectangles on the front page. The left one is as original, the right one has the (single as I see it) hor. constraint removed. When I grab and pull the top right corner they behave the same.

https://cad.onshape.com/documents/59773e82034b45adbeaebc04/w/f6f49358f50641639c0175af

Hope this can solve that puzzle!

Kind regards, Hansrudolf

nav

Hi @hansrudolf in both Cody`s knurl video and my post video we use center point rectangle, in the video below I constrained a point of both your sketches and I`m able to rotate them.

hansrudolf

Ooh - THAT was the secret I didn't see! Many thanks, I can do it both ways you showed in the last example. Again gained a bit of knowledge (ok not too sure about that, I always clear the constraints with the delete key). 

Great help, thanks again,
Hansrudolf