"The selected sub-chain does not touch the branch point"

[HankMcSpank]

What's that message all about?

it's driving me potty - I'm trying to do a countour, but when I chain...I keep getting the message "The selected sub-chain does not touch the branch point"" ....a user manual &/or Google search reveals very little!

To my eyes, it looks like all lines/entities in the design are are touching...but the message suggests not. Is there an easy way of establishing where the problems lies?


Can anyone shed any light on this?

I've attached the file of the design I'm working on when I get the message.

Many thanks!

[Superman]

Have you imported a DXF into mastercam then trying to chain it ?

Autocad, for me has problems with splines and arcs, where it breaks them into small line segments. Ends are not trimmed together

Zoom in to a problem endpoint and see how the ends meet

Easiest solution is to open up the chaining tolerance ( allows the endpoint of another entity to have a little "gap" )
There are Chooks for checking for overlaping entities, and also do a "delete duplicate entities" .

On another similar note, try to create curves from solids, not surfaces. Curves from surfaces also create some chaining errors.

[9 1/2]

Try trimming all joining points. It may "look" connected but no be. For the time it takes, just use the trim functions and double check.

peace

EDIT: so i took a look at the dxf file. there were multiple entities on top of each other (only a few but that will screw up your chaining.)
Trimmed all the corners and it contours fine.

[Matt Berube]

Use "delete duplicates"... That gets rid of some issues...

Then press ALT-C or SETTINGS >> RUN USER APPLICATION...

Then select findoverlap.dll

Window select all of the entities to be checked...

Then you'll probably have to trim some entities to finish it up...

With experience this will become easy...

A favorite tool of mine when tracking down this bad geometry is "Analyze Chain"... It can help to pinpoint exactly where the issue is...

[HankMcSpank]

thanks guys...i tried all your suggestions...it's better but still got an issue (see the screen scrape - top right corner of my drawing seems to be when i get the error).

Here's a screen shot of what I'm getting...

http://img190.imageshack.us/img190/9903/mastercam.jpg

And I've attached (what I think is ) the cleaned up version in DXF!

[9 1/2]

At the point of the red arrow there are three horizontal chains one on top of the other all with different lengths. you must manually delete these layered chains or you chaining efforts will fail.


EDIT: there are 23 duplicate chains and one arc in addition to the ones I mention above.

[diycnc]

if that vertical line isnt split it may fail also. also they may not all be on the same height.

[HankMcSpank]

Thank you once again.

Just to set out my stall...this is a toolholder that someone else on this forum designed in imperial - I simply converted it to metric in Autocad, & imported it to MAsterCam.

In my naeivity, I thought it would just be a simple matter of generating a toolpath - big no! (that said, it's probably my fault as I'm new to Autocad might have uinadvertendly clicked on some lines in error)

So, from the responses I've had above (thanks)...

I selected everything, then went menu - edit - delete - delete duplicate endpoints (in my original file it found some ...so they were deleted).

Next, I selected everything & went Alt-C, selected find overlaps.dll clicked on the green tick - & not much happened (is there meant to be user input after this point)


So to my questions...

A couple of reposnses have pointed, that there are three lines on top of one another, or a vertical line that might need splitting.

how are you establishing this? The design outline looks fine to my (very) untrained eye!

Is there a prescribed method - say at the end of designing a drawing - for finding out, for example...

1. Lines (Entities?) that aren't joined.
2. Lines that overlap.
3. Duplicate lines.

etc, etc

I ran the analyze (entity, contour etc), but there was nothing immediate that gave me that info!

[Superman]

Everyone has had a go, even myself.

And all have missed the one obvious thing that crops up when chaining,...branch piont reached.

Mastercam has chained as far as it can go automatically, it now waits for input from you, at the red arrow end, select the next entity in the chain in the direction you want the contour to go.

Hover your curser over the entity, the one that changes color to creme is the one that will be selected if you L-click ( doesn't matter if 3 or 50 entities lie on top of one another, by doing it this way, you are only selecting one of them )

You can reverse the chaining direction at any time ( switches the red and green arrows around ) ( to do this, it is the double ended arrow in the dialog box )

[HankMcSpank]

Gentlemen...thank you all so much for trying to help me. I've actually now given up....instead I'm now learning how to design my own toolholder (which I should have done in the first place).

The first part I've created, I've been able to generate a contour toolpath with no issue...so it must have been a quirk of importing as a dxf file....

Thanks once again.

[Matt Berube]

Sometimes if you have dirty geometry overlapping, etc... It can be easier to set your "Z" in Mastercam to .1 and use 2-D mode then re-create the dirty contour (.1 above the original)...

Once it's complete delete all of the original (dirty) entities and continue along with toolpathing...

P.S. when you ran the findoverlap.dll, I believe MC was waiting for you to select the geometry you wanted to test for overlaps... Then green check...

[cadcam]

HankMcSpank please review this link showing me profile the outside of the DXF and the issues I found in the file.
I used divide to remove the two segments to make the contour continue but I could of broken the geo and still been able to profile. the file was not drawn correctly in Autocad.
Hope you find this helpful. as you get used to the system you will learn how to find and define issues. I spent about 5min but I also see this kind of stuff all the time from my students to the customers files.

http://www.mastercam-cadcam.com/vide.../designdxf.wmv