Vertical Constraint can't be added? Angled lines are PARALLEL?

[doni49]

I'm trying to develop a dynamic block that will represent a 45 degree fitting for some pipes.  When I try constrain the vertical line, I just get a message telling me that the vertical constraint can't be added.

I figured I'd come back to that and moved on to try and deal with making the angle constrained to be the same at all times.  It's telling me the two lines are parallel!  The two black lines are the ones I'm trying to assign angle constraints to.  What I'm shooting for is the ability to choose a pipe size from a list and have that pick from the block table the od, fc, a & b dimensions and to have all the lines below the diagonal mirror the diagonal.  Any ideas why it's fighting me?  I'm going to post the dwg in case someone wants to see it.

Never Mind.  After continued troubleshooting, I found that they were not all on the same Z elevation.  I moved everything to zero and it's working as expected.

Here's a short video.

[Libbya]

From what I see, I wouldn't use any constraints at all.  I'd just use dynamic parameters/actions and either a lookup or block properties table.

Some of your issues adding constraints may be because your linework is not all on the Z=0 plane. 

[doni49]

I thought lookup needed to use named dimensions and the only way I've seen those created was the with dim constraints.

I'll look into that.

[Libbya]

The dynamic parameters can be used on Lookup tables or on a Block Properties Table.  Constraints can be used on a BPT but cannot be used on Lookup tables.  

[doni49]

Ok.  I went back and tried again.  I think what I was doing in the past was that I tried to use a named dimension in a formula.  That's where I needed to use a dim constraint.

I've assigned names to my dimensions and created the lookup table (right now, it only has two options -- at the extreme ends of the dimension sizes so I can get a visual confirmation that it's working.

BUT.......  I'm having difficulty getting the lines to follow the dimensions.  The end result should look exactly the same -- with only the FC, od and a dimensions changing (fc1 will be the same as fc, od1 will the same as od and a1 will be the same as a).

[Libbya]

The name of your file may be throwing me off.  Are you working on a block that allows different sizes of the 45° elbow, or are you attempting to make a block that allows different sizes of any angle?  I assumed the former, the latter would be considerably more complicated.

[doni49]

Currently working on one that allows 45 degrees at various sizes.  Eventually, I will be working on additional angles as well.  I'm undecided as to whether or should do them as One DBlock or a separate one for each angle (there will only be a few angles).

I've tried using MOVE and STRETCH actions and they didn't show any visual change.

P.S. I was leaning towards having separate blocks for the various angles because I thought it would be a LOT more complicated.

[Libbya]

The reason I am asking is because if you are keeping the 45° angle, then it seems that you only need the OD and fc.  All of the geometry would be set with changes to those two parameters.

FYI your units had degree precision set to whole degrees.  Your angle was off in the last file.  I've never seen any reason to set unit precision below its highest settings.

See the attached file.  

[Libbya]

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@doni49 wrote:

Currently working on one that allows 45 degrees at various sizes.  Eventually, I will be working on additional angles as well.  I'm undecided as to whether or should do them as One DBlock or a separate one for each angle (there will only be a few angles).

I've tried using MOVE and STRETCH actions and they didn't show any visual change.

P.S. I was leaning towards having separate blocks for the various angles because I thought it would be a LOT more complicated.

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It would be relatively easy to have a visibility state for each desired angle.  It would be a lot less easy to have infinite adjustability for the angle.

The reason you were not seeing any effect is because you had the move action associated with the fc parameter's startpoint rather than its endpoint.  When creating a linear parameter, the startpoint is the first point you pick, the endpoint is the second.  A lookup will change the endpoint of a linear parameter in order to change the linear length while the startpoint will remain unchanged.    

[doni49]

I'll check it out when I get home.  Thanks.

The angle will NOT need "infinite adjustability".  There will be a 90, a 45 (this one), a 60 & a 22.5.

[j.palmeL29YX]

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@doni49 wrote:

... with only the FC, od and a dimensions changing 

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Do you really want to change the values of fc, od AND a?  

If that is true, you will get a block which works as demonstrated here (only for fun): 

I can't believe that you expect such a behavior.

I could understand if you say you want to change besides the parameter od one of the parameters fc OR a and additional an angle. This would look a demonstrated here:

(This is not the solution. It only illustrates an example how I can imagine the behavior of such a block)

Before someone spends more time with your block please specify your intention more detailed what you want to achieve. 

Additional: An arc (and two lines) are placed on the Defpoints layer, that means you will never plot it. What is the sense of this arc? What do you need it for? 

[doni49]

Thanks for the assistance!  That did what I needed....for the most part.  Your version removed the inside pipe walls (the hidden lines).  I added them back in and successfully modified the actions that you had created so that they get moved as appropriate as well.  Thinking that I understood what you were doing, I attempted to the same thing for the 22.5 degree elbow.  OMG!  EVERYTHING moves at weird angles.

Just like with the last version, the angle should stay the same and just change the dimensions. 

To be clear:  I'm not asking for anyone to do it for me -- this is something I really want to learn.  But none of the DBlocks I've created in the past used lookups.  They all used visibility to turn things on or off and/or used linear dimensions IN ONE DIRECTION to stretch something out.

Here's what it looks like within the block editor:

Now outside the block editor, I've set it to use "2" from the lookup list:

And this is what it looks like when I use "63" from the lookup list:

I'm' attaching the final working version of the 45 elbow (with my inside wall lines shown) as well as the 22.5 elbow that's currently giving me grief.

[doni49]

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Do you really want to change the values of fc, od AND a?  

I hadn't done the math (yet) to see what that would do.  I was provided with a table from the fitting manufacturer and it included these dims.

[Libbya]

The angle of the fitting is currently set to 23.401839°.  Is that correct or should it be a true 22.5°?  The miter angle is at 11.7009195°.  Should it be 11.25°?

You placed the fc parameter backwards of how I placed it in my example.  If you have the grip turned off then it doesn't actually matter which direction you place it as it will never show.  However, you must remember that the startpoint (bigger X) will never be moved by the changing of the lookup value.  Only the endpoint will move.  Because of that, all actions that you would like to act via the lookup need to be associated with the endpoint, not the startpoint.  The direction the action needs to act can be adjusted in properties after selecting the action and modifying the angle offset property.  The angle offset is relative to the direction of the parameter movement. 

The following assumes that you keep the fc parameter oriented the way it currently is.   

You associated the Stretch1 action with the correct endpoint of the fc parameter.  However, you need to select the Stretch1 action, go to properties and change the angle offset to 22.5 in order for it to stretch in the correct direction.

You associated the Stretch action with the startpoint of the fc parameter.  As mentioned previously, the startpoint is never moved by the lookup, so it will not do anything as is.  Delete it and remake it.  This time associate it with the endpoint of the fc parameter.  Then select it, go to properties and change its angle offset to 180 (it needs to act in the opposite direction of the endpoint movement.

Stretch10 and Stretch11 are set up correctly.

Stretch14, and Stretch15 need their angle offsets adjusted appropriately. 

Stretch12 and Stretch13 need both their angle offsets adjusted appropriately AND their distance multipliers adjusted appropriately.  The distance multiplier changes the distance the action acts over per each unit of movement of the parameter grip point.  The easy way I have found to accurately find the necessary distance multiplier value is to draw a right triangle with one line of 1 unit length in the direction that the parameter grip is moved and then finish the triangle in the direction you need the action to act:

Bear in mind that the value will not be correct if the miter angle should actually be 11.25.

Take a stab at those adjustments and report back with any questions.  

[Libbya · Accepted solution]

I forgot to mention that the od parameter needs to have its Base location changed to midpoint.

I attached an updated version of your block.  I did not adjust the angle to 22.5. 

If you make a single block with visibility states for the different angles, you can use the od and fc parameters along with the some of the stretch actions in ALL of the visibility states and then just add the necessary stretch actions for the modified angles.  You could also use a block properties table for a single pulldown grip that would access all of the angles/sizes.  

[doni49]

Thanks.  I always wondered exactly how the basepoint selection fit into the equation on these.  This should point me in the right direction.  None of the video tutorials I've ever watched regarding dynamic blocks mentioned anything about the basepoints -- they just placed the linear parameter(s) and attached the actions to them.

EDIT:  you were correct in your assessment of the angle.  It IS intended to be 22.5.  I took the previous 45 degree elbow and used the mid point to find the end of the fitting.  There must've been something wrong with the source linework in that block.  I'll go back and examine that closer (the original linework was provided to me as something the boss wanted the fitting to look like -- I hadn't realized the angles weren't correct.).

Anyway, I've corrected the issue and I'm going to repost it here in case anyone reading through this wants to see the final product --hopefully someone will find it helpful on their own road to learning this process.

[Libbya]

I took a quick look at the version you posted.  It looks like you adjusted the linework, but did not adjust the angle offsets or distance multipliers of the various stretch actions so that they match the new angles.  The difference isn't huge, but the block will become progressively skewed the farther it is stretched from the as-drawn state if they are not adjusted to match the new angles.    

[j.palmeL29YX]

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@doni49 wrote:

I'm going to repost it here in case anyone reading through this wants to see the final product --hopefully someone will find it helpful on their own road to learning this process.

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Attached you can find an other variant for such block. It is similar to yours with two main differences. 

- I decited to use an other IMO more meningful base point. 

- Instead of the LookUp table I used a block table. 

 The  advantage of the block table: you don't need to type each of the fc values one by one (and - if you don't have a given tabe with these values you had to calculate each of the fc values manually), but can let do this job an EXCEL file and than simply copy these values from the Excel file and paste into the block table. 

A (perhaps( disadvantage: LookUp tables you can place as many as you want, only one block table is allowed in a block definition. 

My example is not yet complete (it is only to give another view to the issue). 

Your table above doesn't include any information about the thickness of the pipe. Therefore I let it for all sizes to 1.