Linked Values, Equations and using them

[shift1313]

This is kind of a procedural question. I can use linked values with no issues if I have features of locations of things that I want consitent throughout different sketches. I can also create Equations using these linked values by going to Tools>equations with no issue. Where im having issues is trying to create equations in the sketch using linked values. Is there any way or format to use while typing values into the Linked Value dialog box to create valid equations? It doesnt take all that much time to open the Equations dialog in a sketch but id like to know if its needed.

 

Thanks

[shift1313]

Well i havent found any way or format to type into a dimension box or the linked values window that works. The only way I have found is to open the Equation dialog inside the sketch. Its not that much extra work and if the formula was complex you would want to do this anyways.

 

On another note I was able to link values like those for extrude. If you select the feature in the tree, the dimension will be displayed on the screen. From there you can right click and "link value".

[shift1313]

Just another note on this topic. One thing I found to speed up modeling if you have known equations or known values you are going to use. Before you model anything open the equations window, add equations or simply values by naming them. i.e.. Box_Height = 200. This way when you are modeling you can just right click your added dimension, Link Value and be able to use the drop down and pick your $Var :Box_Height. I found this makes edits easier because you can open your equations window, Edit All and change values. If you create a variable in the context of a sketch, link the value and name it, it will not let you edit this value in the Equations window. You have to either enter the sketch and edit the value or click on the sketch and select the dimension when it appears on the screen. For small changes this isnt a problem but if you need to change 10 values at once, the equations window is much faster.

[DannyB]

Sounds useful, will have to try this out. Can't say I have used linked values for repeating modelling as everything is more or less one off designs with many different individual parts.

[shift1313]

Well it doesnt have to be for multiple revisions(even though its extremely useful in that case) but it makes changes to models quicker. Everything I do is pretty much one-offs as well. The benefit comes when you need to dimension something in relation to another part of the design. It could be equation driven curves, offset chains, patterns and so on. It makes changes to large models a bit quicker. For instance say you had the base of you model as a rectangle that was 100x200mm. In stead of dimensioning it that way you can say the W = 2 x H. Say later you want to change their relation you can easily do so from the equations tab. You can also incorporate these values into features and their properties such as draft angles, shell wall thickness, extrudes and so on. Basically you could change several parts of the model from one window as opposed to manually changing each operation.

 

A specific example would be a a small insert i am working on. This insert goes into two other parts to restrict rotation and the geometry of all 3 can vary depending on how the design progresses. The insert has features defined with equations and users inputs(via a design table) until the final design is approved. If to start with I had a set of constraints to follow the flexibility wouldnt be needed but in this case a one off has gone through multiple revisions before its OK to proceed. Until its finalized I can continue work on the other parts using this part.

 

Another little thing is on the Equations Window you can specify all or certain configurations.

 

I honestly dont use it all that often but there have been cases when I wished I had to start with so I try to use it when I can. Even for simple things like dimensions

[DannyB]

Yes, it sounds more useful having described it that way. Especially with concepts that you need to progress further until approved. I think I need to get used to it more as it seems to be part of the CSWP, which I'm looking to do soon.

 

I had a little look at linked values this moring before I got busy. Linking values seemed ok, just right click, link value and name it etc. What I couldn't initially work out was how to relate this linked value to another value e.g W=2xH. Do you need to use the equations tab or make a table to do this after making a linked value ? Shame this PC hasn't got SW on yet, otherwise I'd try it.

 

Cheers

[shift1313]

That was my initial problem as well. I could not find a format where i could type in something in a dimension box(like you can in Inventor). When you link a value and create its name from the Link Value pop up, these dimensions can be used by others(drop down box instead of naming a new dimension in the link values pop up), but i wasnt able to get formulas to work no matter how I entered it. While in a sketch, you can link a value, name it(lets say A = 60). Then you can open up the equations pop up while in the sketch and create an equation(say B = Ax2). When you go to link your next value you will have two variables on your drop down from the Link Value menu. one will just say A, the one created in the equations tab will say $var : B.

 

You will notice in the Model Tree there is a folder named Equations. If you expand this you can view all the variable names and current values.

 

I found it much faster to create my variables on the equations tab rather than during Link Value. Simply for edit-ability from the equation window. If you create them before hand(even if you arent sure of the dimensions) they will already be on your drop down during Link Value.

[DannyB]

Yes, I managed to figured it out today. I was quite pleased with that as I didn't manage to yesturday morning. Like you say if you create them before hand they are there ready to use.

 

Thanks