Trying to constrain sketch to 3d geometry hole...problem

[sleske]

I've been trying constrain a sketch to a hole in another 3d part. Problem is, when I pick the edge of the sketch and the center of the hole to constrain the edge to it creates an angled constraint, then I pick that I want it to be a distance dim. and it gives me a zero dim from the sketch edge to the perpendicular point on that edge in reference to the hole. (I hope that made sense.) I'm unable to find out why it's doing this or how to rectify it. Any help would be appreciated. Thank You!

 

[5050t]

Is the hole perpendicular to your sketch?

 

[sleske]

Yes! I was able to constrain one side to the hole no problem. This other side is perpendicular to constrained side and I doubled check and the hole is perpendicular and hole surface is on same plane as sketch.

 

[sleske]

Add-on! Getting same problem when picking edge of 3D part instead of it's hole. 3D edge is parallel to edge of sketch.

 

[jackk]

2 things you might try:

1. project the edge of the hole (or intersect the face), and then constrain to the yellow feature

2. add a construction line tangent to the edge of the hole, and constraint to the line

 

[DBezaire]

I am assuming you have 2 part files. If so, you should be using an assembly constraint between 2 parts.

Regards,
Derek

 

[sleske]

Thnx jackk! I was able to do it with that. I'm trying to create a part and am using the 3D geometry already in place to constrain it as I make it. Maybe I'm doing this wrong. The part I'm making is a NC block and though i've been designing parts to the default XYZ planes i've been designing NC blocks to the assembly's XYZ. Not sure if this is correct design practise or not. (I guess this question would be apt for another forum.)
Thanks again!

 

[jackk]

Glad to help. Your way should have worked and is much cleaner than either of my workarounds. Not sure what was causing your problem.

Regarding the XYZ origin: I don't think if really matters where the part is with respect to the origin. Assembly constraints should be used to locate the parts with respect to other parts. And I'm sure you have your own Axis System to base the NC data off of.

 

[solid7]

sleske -

1) are the holes really holes?
2) Are they 100% perpendicular to the sketch plane?
3) Do they project as splines or circles?
4) Is the data native?

Here's my explanation:

1) sometimes, the features appear round, but are just "unround" enough to cause problems. (especially with translated data)

2) sometimes you get slightly skewed planes - just barely outside of the model tolerance for recognizing roundness - but corrected by projection. Strange and rare, but troublesome. (had the problem a lot in an earlier version)

3) Splines don't have centers. If the object projects as a spline, see #1 and #2.

4) UG data, in particular, always does this to me. For some reason, the holes are never recognized as round until projected.


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[sleske]

Hey solid7,

1) Yeah the solid I'm using, I created in V5 (Not translated data.) So, it should be round. (Used hole command)

2) I was thinking that a skewed plane may be the source of the problem. Used the compass to make sure it was at the right angles, everything checked.

3) The hole projected as a hole.

4) Yeah the data is native.

Not sure if I just have some setting not set right or something.