Hey All!
I am self taught and use this software for personal and school projects; I’m not a professional drafter nor do I have experience with other software to build on/reference.
I say that for context: I don’t use constraints. I’m not going to say I never have, but they’re absolutely a last resort for me and I feel like even though I make it work, it is ‘improper’, maybe how they Python community would say that a certain line of code will run but it isn’t ‘Pythonic’, or how a mechanic might grab a 14mm when he needs a 9/16 (I think that is the similar SAE value).
So, my questions are twofold. First and foremost, what are constraints when they’re not descriptive, for lack of a better term, such as telling the end of a line segment to be tangent to a circle in a sketch? There must be something like a constrained dimension or locked point or something because I with some degree of frequency get told I can’t use and/or modify a sketch I make. While annoying, this just happened to me again, and after deleting and remaking the sketch, I am getting the same issue. I used a 3 point rectangle instead of a diagonal one and issue persists which prompted me to make this post. How can I identify what this unwanted, invisible to my eyes, unrequested constraint is and throw it in the garbage so I can manipulate my geometry? Show constraints is on and auto constrain is off, referring to the toggle-able options in the cog icon from the constraints toolbar.
Second question, because I’m not opposed to ‘seeing the light’ so to speak regarding constraints, does anyone have tips, tricks, reasons to use them, etc? I did try when I was first starting out but I rarely got the results I wanted and almost always got into a pissing match with the software about how I wanted my shapes and sketches to act.
Thanks in advance!
https://support.shapr3d.com/hc/en-us/requests/new
Forgot to add screenshot of my current frustration…
I think you are being confused with the digital engineering terms that are used for visual CAD design. These are standard names used for all CAD system.
The constraints are just visual locks to help make a drawing into a solid shape. You can draw a rectangle and “extrude” to create the 3rd dimensional shape of a cube and never realize that there are hidden constraints in plain sight to you probably never realized…especially if you drew the rectangle with exact dimension like in the photo (using a width of 10mm and a hight of 6mm)
The app creators intentionally did not clutter the page with big icons or words so that the app could calculate the math behind make a drawing into a 3 dimensional object. They used penny tiny clues to indicate what is going on
All the subtle clues are selectable and deletable.
But some relationships between the joined lines are just easier to completely delete and redraw, rather the zoom in and try to individually change a line lock
if a section you draw does not turn blue to extrude, then they are not “coincident” (or touching/ locked together) simply enter the drawing and DRAW a line through the object to find the misconnection in the drawing
remember… all items are deletable (except purple indicators), even dimensions. All these things “lock” a shape exactly how it’s needed.
It took me a while to get the hang of what “constraints” to what, and in what order you have to select items to get them to “lock together” how you want.
Youtube is your friend.
https://www.youtube.com/results?search_query=shapr3d+constraints
Once you learn this skill, you can use ANY 3d CAD modeling software. they ALL use the same names, icons, and what they do in relation to each other
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Hey Messages4alex,
That was very detailed an helpful; I appreciate the time you took to help me.
Some context that I didn’t realize was needed; in my screenshot, I wanted to move the left edge to the left, as viewed. I wanted it to remain .625" long, but needed to align it with the body in the picture a little differently than I had guess when drawing on the plane that light gray face has.
After reading what you wrote, I need to read dimensions that are displayed even when said line/edge/etc isn’t highlighted as a locked dimension, and I can correct this problem by selecting the 1.1xx" and deleting that value. After this, I should be able to elongate and/or move that rectangle?
What about that purple x? I know you said that indicates the starting point, but I’m not sure what that means. Well, I understand that is where I started drawing from, but I don’t understand how it is relevant. If I draw the exact same rectangle, once from top left, the other from bottom right, they’re going to function the same even though that x will be in a different spot, right?
Thanks again
If you dont have anything selected, and you see dimensions on any lines, then it is constrained to that dimension. and can no long be “stretched”. You would need to delete that reference in order to freely relocate the line.
The little purple X is just an indicator that it was made by the rectangle/circle/elipse tool, and can be moved as a whole with the center dot. Once you “disconnect” the reference (by choosing any dot (node) in that closed section, then the center dot is removed.
The center dot is useful because you can use it to precisely put it at a dimension that you need. A simple double click will select all connected dots and allow for you to move them all together.
Just keep in mind that it CAN mess up other things that have “grabbed” on to a line. The dots are deliberately “sticky” and will lock in once you let go of the mouse click.
You can always remove the little lock to “unstick” the reference and you will see the center dot in the circle disappear.
Once you disconnect any edge the center reference is gone for good. You will have to redraw it to get it back… or “undo” CMD-Z
if you disconnect any lines and the center dot reference is removed, you can just grab the dot, and move it away, and then back on top of where it was before. this will redo the connection.
The double click on a line will give a good indication if the lines are all connected.
anyways, I hope this helps a little.
Good luck
The Purple X is the starting point like mentioned and the starting point where things increase or decrease in size.
For your example the starting point is also locked to the top left corner. When you draw sketch on a face if your sketch end point/midpoint touches the face’s end or midpoint the sketch will automatically lock at that point.
Also if you type in a dimension it’s now locked to that length, if you hover over your dimension you will see a new locked badge which you can click to disable.
Nice explanation. I learned something new. Thanks
