Constraints between orthogonal planes

rune_thorsen229

When a constraint is applied between two planes a scalar projection like  is used, right?. 
Is there a way to constraining, say an equal length, between orthogonal planes?
I don't want to use feature scripts.
What I seek is a way to constrain a line length on top plane to have the same MAGNITUDE/NORM (absolute value) as a line on the front plane. 
Same goes for circles and splines.  

I know there are workarounds: 1. a feature script for 'reading lengths' 2. assigning a variable 3. telling that it's the wrong way. 4. Asking for a 'improvement request'

Example: A horizontal line A on top plane (sketch1). We want a horizontal line on the front plane (sketch2) to be of the same length.  
The intuitive way would be to simply make an equal constraints between two lines ,but no, its not possible. 
What I can do is
step1: make a vertical construction line on sketch 1, which I (strangely enough) can make equal to the horizontal line (because in sketches despite the logic of scalar projections, allows equal constraints to mean: same norm. 
step2: project that construction line to sketch 2.
step3: constrain my vertical line on sketch 2 to the projected line.
Besides being 2 operations  too much for something so simple, this doesn't work with circles etc. 

If that is really the only way it slips my engineering mind why, having implemented and invariant projection in the sketches, this haven't been implemented as an option as a projection between sketches. It shouldn't require more than a few lines of code to implement the 'Equal' constraint variant as being 'Equal norm' !

Have I missed something?

rune_thorsen229

Reference questions: 
https://forum.onshape.com/discussion/comment/6805#Comment_6805
https://forum.onshape.com/discussion/8249/whats-the-easiest-way-to-create-a-orthogonal-line-axis-to-a-plane
https://forum.onshape.com/discussion/comment/60298#Comment_60298

NeilCooke

No it’s not possible. 

rune_thorsen229

Thanks, @NeilCooke
How can I forward this as an improvement request?

NeilCooke

Please create a new IR in the category on the right ->

Entities external to a sketch are projected onto the current sketch plane, like you say, and your workaround is valid. 

Jake_Rosenfeld

@rune_thorsen229

Are these both in sketches?  Why not create a variable and then dimension both lines to have their length be defined by the single variable?  Then updating the variable will update both lengths?

rune_thorsen229

Jake_Rosenfeld said:

@rune_thorsen229

Are these both in sketches?  Why not create a variable and then dimension both lines to have their length be defined by the single variable?  Then updating the variable will update both lengths?

Thanks Jake, You are right about the variables, but say if you had a spline or something then its not possible. 
However I just found an alternative but its an ugly hack. Making an assembly where the sketch is imported twice but fixed orthogonally and then do in-context design. 

Jake_Rosenfeld

@rune_thorsen229

It is possible with spline.  See description of Arc length/Curve length dimension here: https://cad.onshape.com/help/Content/sketch-tools-dimension.htm

lougallo

Variables will be the way to do this and we will be working on ways to make this quick to add variables on the fly:  Vote here:  https://forum.onshape.com/discussion/comment/33056