Keep only certain features in mirror?

[chairilNTAB7]

Hello everyone: I am brand-new to Autodesk Inventor and would appreciate some help on the following. Attached are .ipt files and an Inventor screenshot of a flow manifold. In the original manifold (20181031_Split_4.ipt), the diameters of all four channels are identical, at 0.0625 inches. My main objective is to make the diameters of each of the four channels different.

In the modified manifold (20181031_Split_4_mod.ipt), I was able to alter the diameter of the leftmost channel by removing the driven dimension there. The second channel from the left will stay the same at 0.0625 in. However, since there is a Mirror defined (Mirror1) in the file, I can't independently change the third and fourth channels. They are linked to the diameters of the 2nd and 1st channels respectively (Sketch38 and Sketch39). On the other hand, deleting or suppressing the mirror will also remove the internal channel geometry, and I am not confident in my ability to rebuild those from scratch.

My questions are:

1) Is it possible to keep the mirror and all features, except change the diameters in channels 3 and 4 by unlinking dependence to Sketch38 and Sketch39? I have been unable to do this by using the "Edit Features" menu for the mirror.

2) I get the error message for the modified Channel 1: "The attempted Loft operation had problems with the specified rail curve not intersecting one or more sections. Try repairing the rail curve so that it intersects all the sections." I am not sure how to resolve this issue. What is the estimated impact of leaving this fault as-is on 3D printing? The internals look ok to me.

Help is greatly appreciated!

Thanks!

[gmwi]

You can use "direct edit" to make changes after the mirror command. You can stream-line a lot of your features with some other program command. 

The loft error needs a center guide rail to make the size change. The program LIKES to calculate things so help is needed from time to time.

[SharkDesign]

There's only 4 features so you'd be better off just redrawing them. If you really want to mirror, you could pick one of the features the stay the same and then use that as a reference to model around it. You can't unlink dimensions though, it wouldn't be a mirror then. 

If they were all supposed to be driven from one, I would reference the first parameters in the later sketches so I only have to update one to update them all. 

You can't 3D print from inventor, so as long as your STL export looks how you want it, it'll print. There could however be slight dimensional inaccuracies if you are getting an error in Inventor though.