Boundary Not Closed Message

[Rob Holowack]

Occasionally my high school student's get the "Boundary Not Closed" message when attempting a pocket operation. It usually takes a while to find either the duplicate entity or unjoined corner and fix it.

Can anyone suggest a quick / efficient procedure for correcting the problems which could cause this message.

[cadcam]

I find for a quick way to see .

Is use "screen" "endpoints" alot of time then you can see if there is points in the middle of a long line wnd if you see two points real close ant a end altt of the time there is a break.

[Trevor Bailey]

Instead of creating points everywhere, you may also "analyze-chain". This will show where the chain stops/starts or breaks. Then you just need to trim or patch the entities. If you are working from an IGES file or the like, create your curves and then "squash" the entities at the desired depth for that particular toolpath.

[cadcam]

I agree with Trevor to this another way that I do things to.

There are a few just have not stated all.

I am guessing that your students are working in 2D at this time.

[Michael Reynolds]

This actually happened to one of my students today. We tried all the above suggestions (all good, of course), but when all else failed, we did a "screen", "statistics" and found that two of the entities were splines, which mcam does NOT like to chain. Changed the splines to arcs, and off we went!

Hope this helps!!

Mike R.

[cadcam]

Now mike i find this to not be a problem.

I push splines and lins along with arcs all the time.

Maybe the splines were not in the same "Z" plain by a small amount.

put you can you slpines and arcs,lines in the same contour.

[Michael Reynolds]

Hi Jay!

The spline was on the same z level as the rest of the geometry. All's I know is that when I created the arcs and deleted the splines, the toolpath worked. Mabye I have a bad setting in my config file?

BTW, did you get the new "mill" tutorial with the instructor book? If so, whadaya's think?

Thanks!

Mike R.

[cadcam]

Are you talking about the new mill training book?

If so i just saw it yesterday but have not purchased it yet.

[Charles Davis]

Likely if you look closely at the endpoints of the splines, they did not connect with the adjacent line/arc entities.

If the spline actually shares endpoints with other entities, they definitely will chain.

All I can think of is the spline didn't touch the adjacent entities, but was very close. The chain tolerance wouldn't automatically join the entities (notice how splines are difficult to trim unless they actually intersect the trimming entity).

When you converted the spline to arcs, the chaining tolerance would work.

Just guessing; but the central problem is the entities were not connected, and that should always be solved using Trevors suggestion before proceeding. My 2 cents.

[Rob Holowack]

Thanks for all the excellent advice. Should save us a lot of time when this problem comes around again.

[Guest CNC Apps Guy 1]

When I've had problems chaining splines and arcs/lines for toolpaths, I've found that the endpoints were not in EXACTLY the same place. They varied on averave .0001 or so. The one key way to tell if things will work as planned is if when you select your chain, pick it close to the start of an entity, if the chain arrow moves to another section in the chain, you've got a problem. Try "squashing" the spline, this has worked for me in the past, if all else fails, create points along the entity , create a bunch, create points at the end points of the entities you're tying to chain to and create a new spline.

JM2C

[Guest CNC Apps Guy 1]

Dang Jay, you live in here or what?????? You're trying to post more than me huh? j/k I've been busy racing BMX, spending time with the kids and teaching, oh and work too.

Later,

[cadcam]

Well I warned you a few months ago when you went to Oregon.

The Race is on and jay is coming up fast on James bike but just not.

Close enough.

[Scott Bond]

Hi

Jay ,James and fellow race fans:::

This december 15 I am haveing my birthday party at the santa calrita BMX track. On a satureday single point race night. Jay I'll have a bike for you at the track. If anyone one else would like to attend,,,,, bikes for you as well.

The post race determans who is the poster-child

The BMX race determans who is the first looser.

"THE RACE IS ON"

[Chips Ahoy]

Did you ever use the C-hook "Squash" I've used this a few times and it works wonders if you want all your geometry on the same plane. Rick

[cadcam]

I use that C-Hook vary often.

It has helped me in many cases.

[Michael Reynolds]

James, Jay & Ricky:

Hi guys! So I'm sitting here trying

to do a "cut away view". I create a

spline around the geometry I want to

hatch. I get the same message about

"chain not closed". So I tried the "squash"

c hook on your advice. Worked like a charm!

 

Thank you, thank you, thank you!!!

Mike R. (lifelong mastercam learner)

[cadcam]

I will say you are welcome from James, Jay & Ricky.

[Chips Ahoy]

We like "Squash"

[cadcam]

I agree ricky it tasts preaty good with a little chesse on top.

[Guest CNC Apps Guy 1]

Try some cinnamon and sugar too, it's great.

[cadcam]

James really it does taste good .you have tried this.

I would of never thought of that.

ok i will remember this.

[Guest CNC Apps Guy 1]

My Grandma used to make it when I was a kid. Very tasty indeed.