Angle constraint

[msmit]

The following has me puzzled (and quite frustrated)

To constrain a part in an assembly using two planes or surfaces, I only get the options: coinside, allign and ofset. The option angle only appears sometimes when there is already an angle between the two. Is there a way to force setting the angle between the planes?

any help, solution or work around would be greatly apreciated.
Cheers,
Smitje

 

[kdem]

To get an angle constraint you need to specify an alignment constraint between two axes, two edges, axis and edge. For a mechanisim constraint you can specify an angle with the cylindrical constraint.I don't remeber if there are others off hand.

 

[msmit]

@ kdem: Thank you for your help I will try using an edge or axis instead!

@all:
However, sometimes "angle ofset" does appear when constraining tho planes or surfaces or a mix. Does anyone understand when this happens and how to force it, because it is frequently unavalable when I need it.

 

[kdem]

Can you give an example of when you have seen this. One constraint I forgot to mention that you will see this with is an insert constraint whichaligns axes.

 

[msmit]

hi kdem,

I just did some testing in my model and as you say I do get an "angle ofset" between two planes, after adding an "insert" between two cylindrical surfaces. This makes sense when modeling anything that hinges like this. But how would I assemble for instance a cube in a diferent orientation than along the existing datumplanes

one trick i used sometimes is to create a datum at a random angle, ten use that to get the "angle ofset" and fill in some number, and then change the reference to this "random datum" to the datum I originally wanted to reference. (but that would first only give me coinside allign and ofset) and then throw out the extra datum.

cheers,

 

[kdem]

From what I can find out it looks like the method you are using to create an angle is the method you need to use to angle a cube at a random angle. The offset angle constaint from what I'm reading was intended to be used with the insert constraint although you can create one by aligning axes and edges, and it can be created with the mechanism connections pin and cylinder.

 

[msmit]

this point Remains a PITA for me so an aditional post...

For reasons that elude me the technique I described above only works if you use insert but not if you use axis align. Does anyone have an idea why this might be? To me they look perfectly equivalent in all ways including mathematical.

Cheers,

 

[dgs]

Try using ctrl + alt + middle mouse to spin your model slightly before you add constraints. If you get it off of square, you should get an angle constraint.

For me, I ahte that it assumes it because I usually don't want it.

 

[jayanta.diff]

In proe angle constant will be available when proe can not have any other choice except that. So make every constant before selecting for angle constant. e.g for any hing first select the axes to align, then perpendicular planes to axis to mate or align, then u will see the offset icon will be change to angle constant one.