Flip plane orientation

andrew_troup

It took Solidworks nearly twenty years to get around to letting us specify which side of a reference plane was "Up" (green) and which was "Down" (red)  -- Flip Normal, new in SWks 2014.

Please don't overlook this highly desirable command for OnS, when development schedule permits. It's not a must-have, obviously, but it's very much a nice-to-have.

It's important in models, (not just assemblies using SW-style mates between planes) particularly once you implement pasting geometry into a sketch, or derived sketches. 

andrew_troup

An example of where this capability can save time and headscratching:

Say a bracket has been designed with various lugs welded on to planes provided at various angles. A design change, or discovery of a misunderstanding, means that some of the lugs need to be swapped to other planes (they're right shape, but wrong plane).

In reassigning the sketches to the correct planes, some lugs end up flipped, being effectively pasted on the wrong face of the plane. 

In other packages, all external constraints will have to be identified, noted, and deleted. A "mirror sketch" operation will have to be invoked. Then the external constraints re-established.

How much easier would it be to simply flip the plane?

chris_houser

Wishing for this right now. Is there no workaround these days? The plane I'd like to flip is defined using point-normal. I thought choosing as a normal a line that approached the point from the opposite direction would be enough to flip the plane, but apparently not. Any other ideas?

EDIT: I take it back. I changed the order in which I chose the endpoints when drawing the normal line, as well (in various combinations) changing the side of the point the normal line fell on -- some combination of these did flip the plane.

peter_newman

I created a helix on the Top plane with a pitch of 69 mm and 0.25 turns. I can create Plane1 at the endpoint of the first helix and draw a circle for a second helix. I want the second helix to go down toward the Top plane, but negative numbers are not allowed in for helix creation. Since Plane1 is "up" I can only draw a helix going up, but I want to go in the opposite direction. How do I create a plane that is pointed down relative to Top?  Link to example.

Here is what that looks like in Onshape.

I was able to do what I wanted in SOLIDWORKS. 

owen_sparks

@peter_newman

Is this what you're after?



Changes made:-
(1) Helix2 - Flip Direction (Arrow Icon next to "Turns and Pitch")
(2) Helix2 - Change to "Counterclocwise"
(3) Helix2 - "Start Angle" to 270 deg
(4) Sketch3 - Apply coincident constraint between centre of circle and Helix

copy here:-
https://cad.onshape.com/documents/58da0746d31be40fe1f66b18/w/907c2c2809ba4541ef13bc44/e/5637086a00983146ea7b8376

If I've missed the point and this is not what you need then sorry, I'm still pretty new to all this.

Cheers, Owen S.

peter_newman

Thanks Owen, that is exactly what I wanted. I'm very new to Onshape and am still learning the basics.

owen_sparks

No worries, happy to help. 

I'm the other way around.  New to CAD but been playing with OS for a while.

Cheers Owen S,

peter_newman

I created a helix on the Top plane with a pitch of 69 mm and 0.25 turns. I created Plane1 at the endpoint of the first helix and draw a second helix. I want the second helix to go down toward the Top plane, but negative numbers are not allowed in helix creation. Since Plane1 is "up" I can only draw a helix going up, but I want to go in the opposite direction. How do I create a plane that is pointed down relative to Top?  Link to example.

daveaseeman

Hi All,

I actually figured out a way to do this, although it's a little hacky...

1. Click "Mirror" then select "Feature mirror"
   
2. Select the Plane you want to flip as both the "Features to Mirror" and "Mirror Plane"

That's it. Optionally, you can hide or delete your original plane, leaving only the plane with the flipped normal. The plane didn't have a name/title on it for me, but I didn't care about that.

Hope that helps.

Dave

johan_van_ravenhorst

A related improvement request:
https://forum.onshape.com/discussion/1304/ability-to-flip-orientation-of-planes

MBartlett21

peter_newman said:

I created a helix on the Top plane with a pitch of 69 mm and 0.25 turns. I created Plane1 at the endpoint of the first helix and draw a second helix. I want the second helix to go down toward the Top plane, but negative numbers are not allowed in helix creation. Since Plane1 is "up" I can only draw a helix going up, but I want to go in the opposite direction. How do I create a plane that is pointed down relative to Top?  Link to example.

@peter_newman
@daveaseeman
@johan_van_ravenhorst

You can use the Opposite Direction button in the top right corner of the feature