Overly Complex Code with Simple VCarve Toolpath

This forum is for users to post tips and tricks they have found useful while working with VCarve Pro
CNC_Simon
Posts: 3
Joined: Sun May 17, 2020 2:07 pm
Model of CNC Machine: Ooznest Workbee with Mach4

Overly Complex Code with Simple VCarve Toolpath

Hi Everyone, I love my CNC and VCarve Pro....but.... all my V-Carve tool paths (ie with a V Bit) produce lots of seemingly unnecessary air time. While at each cutting depth, the tool lurches back and forth cutting random parts of the letter when logic (as I see it!) would have it stay in the area in question and continue cutting, rather than doing a bit, flitting off to another area only to have to return seconds/minutes later to carry on the same cut. I have tried changing 'Use Vector Start Points' and 'Use Selection Order' and grouping 'V' vectors before calculating the tool path - and while that can make a more logical progression along a word, the business of flitting about within each letter still occurs. I know I can't write the GCode to do this complex work (like engrave a long word with 2" letters for example) but if I could I think I'd approach it more logically? Can I change any settings to get the built-in V-Carve toolpath to tackle the task with less air time? Or is it just the way the algorithm does it? Grateful for any tips/tricks. Many thanks, Simon

Vectric Wizard
Posts: 3457
Joined: Sat Jul 27, 2013 10:08 pm
Model of CNC Machine: AXYZ 4008

Re: Overly Complex Code with Simple VCarve Toolpath

Without pictures or file to examine it's difficult to evaluate whether something is overly complex or not.

CNC_Simon
Posts: 3
Joined: Sun May 17, 2020 2:07 pm
Model of CNC Machine: Ooznest Workbee with Mach4

Re: Overly Complex Code with Simple VCarve Toolpath

I'll post a pic from Mach4 tomorrow showing the density of air moves generated by the V-Carve tool path on a simple letter. Machine at workshop! Meantime, you can maybe imagine a zig zag of air moves that give an 'interrupted' cut that might, more logically do the cutting in each area without nipping off to another part of the letter - it really is too complex! Cheers Simon

Rcnewcomb
Vectric Archimage
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Re: Overly Complex Code with Simple VCarve Toolpath

We really need to see the .CRV file (copyright permitting) in order to determine why the toolpath is overly complicated.

If the .CRV file is too large to upload here you can use a file sharing site such as drive.google.com, onedrive.com, or dropbox.com. They all have free accounts available
• Upload the file to the file sharing site
• Share the link to the file here
For screenshots please use the Windows Snipping tool. These are far easier to read than photos taken with your phone.

On many Windows systems you can also use <Windows-key><Shift><S>
- Randall Newcomb
10 fingers in, 10 fingers out
another good day in the shop

tomgardiner
Vectric Wizard
Posts: 428
Joined: Thu Oct 02, 2014 1:49 pm
Model of CNC Machine: FMT Patriot 4 x8

Re: Overly Complex Code with Simple VCarve Toolpath

It is the nature of the beast that a V carve toolpath might jump about in my experience. Your example sounds more extreme than I have had though.
If the work is broken up into distinct islands of carving you could make selections of vectors and make multiple copies of the toolpath for each island. This will keep the jumping around to a minimum. You can save all the toolpaths to one file.

Vectric Wizard
Posts: 3457
Joined: Sat Jul 27, 2013 10:08 pm
Model of CNC Machine: AXYZ 4008

Re: Overly Complex Code with Simple VCarve Toolpath

While waiting for an image or a file you might want to look up the "travelling salesman problem" to find out why the program is doing what it's doing.
The Traveling Salesman Problem (TSP) is the challenge of finding the shortest, most efficient route for a person to take, given a list of specific destinations. It is a well-known algorithmic problem in the fields of computer science and operations research, with important real-world applications for logistics and delivery businesses.

There are obviously a lot of different routes to choose from, but finding the best one—the one that will require the least distance or cost—is what mathematicians and computer scientists have spent decades trying to solve.
Emphasis mine. If you have enough computing power and time you can come up with a much much better path for a large set of points. Are you willing to wait hours for a toolpath recalculation?

wolfeman
Vectric Apprentice
Posts: 63
Joined: Sat Jan 27, 2018 4:15 am
Model of CNC Machine: Xcarve

Re: Overly Complex Code with Simple VCarve Toolpath

Mine does that a lot too. Spends to much time jumping from one side of the cut to the other (air time) just to punch a small hole then back to the other side to punch a small hole (rinse and repeat) when it could just cut along a path and stop all that back and forth. No I am not a programmmer but it seems to waste way to much time. Sometime adds hours to a cut.

Rcnewcomb
Vectric Archimage
Posts: 5363
Joined: Fri Nov 04, 2005 5:54 am
Model of CNC Machine: 24x36 GCnC/WinCNC with ATC
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Re: Overly Complex Code with Simple VCarve Toolpath

It would be helpful if someone could post an actual CRV file that is displaying the problem. It helps the developers at Vectric when they have an example to use for troubleshooting and enhancements.
- Randall Newcomb
10 fingers in, 10 fingers out
another good day in the shop

Leo
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