Thursday, 4 December 2014

Tube and Pipe 3

On first and second part we have discussed, naming and constraining your tube and pipe assembly, projecting the run planes for route constraining and importing styles so we don’t mess about with the default template.
The next thing I like to do while inside my route is Import Parameters. You don’t have to follow all this steps and I understand it might seem too much for doing a small route but it’s better to install these habits one at a time and stick with the ones you really need (find useful). I can’t help but do them all no matter how small the assembly. When you have all the time in the world to design a spool you don’t need these but when the day comes hot and heavy you will find them useful.
 What do you mean by saying Import Parameters from xml? I have a set of parameters with same name but depending on the pipe size they have different values and different description.  These are just measurements I’ve done on my fittings (most commonly used ones) in order to see how much space they take. This will help in tight confined spaces, as well as keeping the routes visual appealing.
These are the parameters that I import for a DN32 PVC-U route.

I have a set of parameters for each size-style. For DN32 PVC-U one xml file, DN32 PVC-U DN25 another xml file, DN32 ABS a different one again and so on. I use these parameters to dimension the distance between the nodes, based on what fittings I will have on the node. 

Ex: Ball valve after an elbow will have the distance between the nodes as “=e+vb+gp” (elbow parameter + ball valve parameter + gap parameter) or because it’s so common I have another parameter “ebg” that holds this sum as a formula “ebg = e+vb+gp”, so in this case I will type just “ebg”.
Unfortunately, when dynamically entering dimensions by typing the value (while holding your mouse over a reference), you can’t enter any text value so you won’t be able to type “ebg”. You can start typing a number and then in the dimension value dialog type “ebg”. Inventor will calculate the value but will not put the equation in, just the end result.  So when you edit the dimension (if you used auto-dimension) you will see the end result as 95mm instead of “ebg” what we wanted.

That’s why I just place nodes by clicking a couple of times in the desired direction and dimension right at the end using my parameters as values. If you don’t care about your dimensions, don’t bother doing this, you’re better off skipping and dimension by the “eye”.
When you start, after you select your first point (circular edge, or point) an arrow will show up indicating the direction of the route. You can change the direction either by pressing space bar or by typing a negative value while holding the mouse over the arrow vector. Because Inventor projects the plane of the circular edge and dimensions to a plane can have a negative or positive value, you can switch direction with negative sign. 

        You can enter dimensions by using right click on the reference, triad, start vector, or any face or plane your mouse can select. I don’t use the right click menu, I use + and – to increase the triad or starting vector and while holding your mouse over the reference I start typing my dimension.

If you need to use planes or faces as references, right click and activate point snap, and while holding your mouse over the face or plane start entering the value. 

If you type 100 it will create the segment 100 mm over the reference (more than), while if you type -100 it will create the segment 100 mm to the reference (less than). In my example I am holding the mouse over the wall face and type -100 to keep the nodes and segments inside the room. Inventor will not create a dimension from your node to the reference, but instead will dimension the length of the segment. I don’t want to auto-include geometry, references, and things that might change. If I want to dimension my node from the wall I will first use include geometry on the wall face.

Till next time,