Align difficulties without reference points/edges

[Helmi74]

Hey there,

i'm still struggling with guidance and alignment in Fusion360. This is something that is generally often unclear in Sketches and other situations. Here's an actual example i'm often struggling with when trying to align objects that don't have a corner/edge that play well with where i want to align it to.

In this case i want to align the cylinder to touch the extended x and y axes - basically i want to align its "surrounding box" (that isn't there) to the origin point of the WCS.

Probably i'm just missing the intended way to do this - ideas?

Thanks!

[Anonymous]

Thinking about it more, I realize it's not explicitly a tangent joint, but more of a work around.  An explicit tangent joint would be nice I suppose for cases like these, but it seems like in the meantime this work around should be pretty effective.

Jesse

[Anonymous]

And just to outline what's involved in quickly (once get used to) these "tangent joints". 

1) Ground the block components.

2) Create a planar joint between the cylinder and one of the block components, such that the cylinder axis is normal to the planar joint plane.  To make things go quickly, is preferable to place the joint origin for the block component in the "armpit" near where the cylinder is desired to ultimately rest.

3) Create a contact set, which will prevent the cylinder from intersecting with the blocks.

4) Set joint limits for the planar joint, activating for both planar joint axises the Rest option, which will apply a force on the cylinder to coax it into always returning to an established rest position.  To help insure the cylinder doesn't ever jump to the other side of the blocks, one can set the rest position slightly off center from the armpit.

5) Move cylinder to general desired position.

6) "Activate" everything.  This can be done by toggling Lock for the planar joint.

7) Set desired rotation angle for the cylinder, then lock in this angle via setting it for the min and max planar joint angle limits.

If a component undergoes a change that modifies the relationships of these "tangent joints," new relationships can be reestablished by again toggling Lock of the planar joint.

Jesse

[HughesTooling]

Hi Jesse

Thanks for doing the screencasts, very nice workaround. Although it's a bit more work it looks like it has more uses as it will maintain contacted between components across more then the one surface a tangent would allow. I'll have to experiment with it a bit and hope I can remember the technique the next time I need it.

Thanks Mark