New Dynamic Block

[matthew.mccormack2257W]

Hi all...

I'm trying to create a new dynamic block, its a block used for round bends in mechanical ductwork...

what I'm trying to get it to do is to, be able to enter an angle and it'll draw that angle of ductwork. or to be able to stretch a line around a centre point, so I can stretch it to the angle I need.  so for example in the attached dwg, I need the green lines to remain attached to the RED at all times... the RED line to stay stationary in its position and not move, The green lines to move and stretch around the centre point, which is the centre of the magenta circle....   the current angle of the bend is 35 degrees, i need this to changeable from 5 degrees to 90 degrees max.

I hope this makes sense and can anyone help...

Many thanks in advance

Matt

[hwalker]

If you have full AutoCAD it would definitely be possible using constraints.

[matthew.mccormack2257W]

I have tried using constraints, because I can imagine that's how it needs to be done but I can't get them to work for me in the right way... 😞

[hwalker]

@j.palmeL29YX you might be able to help with this problem

[j.palmeL29YX · Accepted solution]

Based on the given (in my opinion not really meaningful) geometry I'd do it as shown in this video. 

[matthew.mccormack2257W]

Thanks for the video tutorial.. I've created a new bend following the video guide and its nearly working perfectly so I'm not quite there...

to start I've deleted the inner margenta circle marking the cen point as i didnt need that but everything else is there....

I've added all the geometric constraints and parameters as per the video guide, but the block is not behaving correctly in the sense the vertical line is rotating on its own end point instead of from the cen point of the arc's and the inner arc is not stretching back when I change the angular parameter to a shorter angle....

does this make sense? can you help? see attached new dwg

[matthew.mccormack2257W]

got it, just figured it out and its working...

I put locking geometric constraint at the end of the construction line (cen of the arcs) and the vertical line is rotating where it needs to now... 

🙂

[j.palmeL29YX · Accepted solution]

FYI: 

For this new initial geometry (all arcs share the same center point) the block can be much simpler (less constraints). 

If my reply solves your problem, click the "accept as solution" button. This can help others find solutions faster.

[matthew.mccormack2257W]

Perfect, Thank you all for taking the time to reply... much appreciated...

I'm getting more use to the geometric constraints now...