anyone see any errors in this file?

[knight_toolworks]

can someone check these parts? I can't find any errors but if I select them as a outside cut I get a oversize square hole. I can cut the holes seperatly but it makes me wonder what is wrong with the part. I can't find any overlapping lines or any other errors. this is in vcarve 5
http://dl.dropbox.com/u/1939753/186%20Billy%20Goat%20Top%20Mold%20Tail%202004-1.zip

[dana_swift]

Steve I dont see anything wrong with them, what specifically is the problem you are having with the file?

The holes are round, 0.5" diameter, you can pocket them or drill them with a 1/2" bit.

The curve shapes are all closed, so they should cut fine. I set up an outside profile on them just to check, and it worked the way I expected.

I am using Apire v 2.504 if that is a factor-

D

[knight_toolworks]

did you select the holes and the outside part? if I select it all and chose outside cut the holes are toolpathed as oversized squares. if I only select one it is fine. but if I select both then I get square holes. if I choose inside cut then the holes are cut on the outside but they are round.
it was very strange and I was not sure the part was right. I thought the drawing had some wacky thing I was missing. I replaced the holes with real holes as the ones were not perfect and that did not help. my customer had a lot of problems getting the file right with importing errors.

[srwtlc]

Interesting! If you make the circles 0.51 it makes a circular toolpath or if you adjust the tool diameter for a 0.25 bit to 0.248, it will also make a circular path. Otherwise it's square. Not that I'd ever toolpath both together in that manner, but....

I'm running the latest Aspire.

Ummm, Brian.....:confused:

[knight_toolworks]

why would you not toolpath them together? they are all through cuts.
that is weird about the size. wonder if you change the bit to .249 it would work? have to check that tomorrow.
I had so many problems with their files because they kept goofing up it took more time then it would have to cut all the parts out.

[adrianm]

I can't actually get it go wrong in the way described but I expect the problem is along the same lines as not being able to pocket a dado that is exactly the same width as the bit used.

Changing the bit diameter or vector size by a fraction solves it.

[Brian Moran]

Hi Steve,

Can you send the CRV file with the toolpaths to support at vectric? Playing with your DXF I'm not seeing any errors, but I have no idea what settings you are using.

Thanks

Brian

[tmerrill]

Steve

In the setup for the Profile Outside toolpath select the Corners tab and uncheck Sharp External Corners. Then you should get round holes.

I've sent details to Vectric but you should still send them your .crv file as they requested in case there is something else happening.

Tim

[srwtlc]

why would you not toolpath them together? they are all through cuts.

Not that it's wrong, just habit that I generally do profile cuts last and then combine any that use the same tool when posting the .sbp file. Also, I may want different parameters for just the holes than I do the profile, like leaving several thousandths for a final clean up pass or onion skin.

Scott

Edited: Good catch Tim. Funny why it will only do it when the part profile is selected with the holes though. I can make it happen with a new file with a rectangle and 0.5" circle using a 0.25" bit outside profile.

[dana_swift]

Steve I decided to examine the DXF file itself. There are very suspicious things in there "tab characters". This makes no sense in a DXF file. Technically the data is still readable, however the tabs are found in many many places, but consistent. For instance:


POLYLINE
5
42
8
TOP_MOLD
66
1 << there are two tabs here, spaces ok, tabs suspicious
10
0.0
20
0.0
30
0.0
70
1 << there are two tabs here, again why?
0
VERTEX
5
FD
Note the second case I pointed out, parameter 70 which has a value of 1. According to the DXF file format specification (DXF Reference is u19.1.01 Autocad V 2008):


70 Polyline flag (bit-coded); default is 0: 1 = Closed; 128 = Plinegen
This value of 1 tells the reading programs that the vector is closed. Interesting that your problem seems related to this parameter being interpreted correctly. If the 1 is being ignored or not read, that could account for the problem.

Now how to fix it?

Read the file with Autocad (or a clone), save as DWG. Reopen the DWG and re-save as DXF. Now the DXF file will be re-generated from scratch and the offending tabs should be removed.

Hope that helps

D

[dana_swift]

Addendum-

Note the tabs were "eaten" by the forum software, trust me they are there in the DXF.

I examined the DXF using Notepad++ if that info is of any use.

D

[tmerrill]

You can clean up the file from within VCP. Just select the circles and use the Fit Curves to Vector tool to change them to circular arcs.

It worked in this case.

Tim