Turning Hinges by Degrees

bart_harris

How would one go about turning a revolute mate by a set number of degrees? I have tried right clicking and clicking "rotate 90°" but it just says "Moving instances had no effect."

What am I doing wrong? Here is an example:

https://cad.onshape.com/documents/6851b01973b14124bcd6224a/w/44ab6ee4efae4df08c015b92/e/5258c56a268142e3a9692cb0

jakeramsley

For your example, I would just rotate the alignment of the mate.

1. Edit "Revolute 1" either by double clicking on it or RMB and choosing "Edit"


2. Click the "Reorientate secondary axis" button or press 'q' for the shortcut.  This should realign the mate and rotate it 90 degrees.  Press this until it is in the right quadrant.


This changes the angular alignment of the two mate connectors.  If you need a specific angle, you can edit the mate connectors that define this mate and rotate one to the desired angle.  From here, you just need to set the mate alignment correctly.

3dexter

@jakeramsley could demonstrate this situation " If you need a specific angle, you can edit the mate connectors that define this mate and rotate one to the desired angle.  From here, you just need to set the mate alignment correctly."?

andrew_troup

It seems to me that solving a problem is often 80% diagnosis, and 20% devising a solution

And methods of diagnosis tend to be much more generalised and powerful than individual solutions, with the fringe benefit that they're easier to acquire.

Rather than ask to have each exact problem solved by the master, I wonder if it would help more people towards a deeper level of understanding if those of us who have stumbled at some of the same obstacles, shared some of the tricks we used to work out the solutions for ourselves?

Here's one from me, to "start the bidding"

Onshape is currently very deficient in diagnostic tools, and this can be challenging when dealing with constraints, and with mates. Just one example: We can't (yet) click or RMB on a mate connector in the list within "Edit Mate" dialog, to find out which part, if any, that connector belongs to. 

And when two connectors are superimposed (as they generally are when creating a mate), the screen display is almost no help to us.

So what I tend to do is temporarily "Offset" the mate (checkbox tick) by an arbitrary amount.
I generally type something evidently nonsensical, like 12.345mm. I sometimes get dragged away by an urgent query and might otherwise lose track of what is "kosher" modelling, and what is a temporary kludge.

Suddenly the connectors (and more importantly, their coloured axis designators) can be inspected separately. If you press "animate Mate degree of freedom" (resembling the "Play" icon for a music player) you will see which connector belongs to which part.

jakeramsley

3dexter said:

@jakeramsley could demonstrate this situation " If you need a specific angle, you can edit the mate connectors that define this mate and rotate one to the desired angle.  From here, you just need to set the mate alignment correctly."?

Sure thing.  If I want to have the hinge be rotated at 27 degrees, I would hover over "Revolute 1" and notice that the mate connectors are pointing in the same direction.  This means I should be able to rotate either one of the mate connectors and have it rotate with it.

1. Hover over Revolute 1 to get the alignment of the mate connectors.  I'm looking at the blue/z-axis and in this case as I only see one it means they are in the same direction.


2. Expand the "Revolute 1" mate connector list and choose one to edit.


3. While editing the mate connector, select "Move".  This will show me the controls to move my mate connector.  Based on the alignment of the mate connectors, I'll want to rotate it about the z-axis to get a 27 degree angle.


4. Enter 27 and hit enter.  Notice the mate connector rotates, but the parts don't.  This is because a revolute mate has a free degree of rotation in this axis.


5. Now that we have all of our mate connectors lined up, we can reset the mate back to its default position.  This won't lock it there, but will put it back to the starting position, which is 27 degrees.

michael3424

andrew_troup said:

It seems to me that solving a problem is often 80% diagnosis, and 20% devising a solution

And methods of diagnosis tend to be much more generalised and powerful than individual solutions, with the fringe benefit that they're easier to acquire.

Rather than ask to have each exact problem solved by the master, I wonder if it would help more people towards a deeper level of understanding if those of us who have stumbled at some of the same obstacles, shared some of the tricks we used to work out the solutions for ourselves?

If the masters have the time, I think that sharing the tricks can far more helpful in as much as it takes the user to a deeper layer of understanding for how Onshape can be used or maybe to a better understanding of the philosophy of it's use.  Your example was a good one that I'll be using in future.

3dexter

Thank @jakeramsley .