pocket depths

Discussion/questions about software used with your CNC Shark and programming issues

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albers
Posts: 13
Joined: Sat Jun 10, 2017 10:39 am

pocket depths

Post by albers »

I have programmed a pocket to be cut with several successive depths because of the overall desired depth of the pocket. When programming a pocket at several depths, the *.tap file shows that the tool retracts to clear plane between the successive depths...is there a way to prevent this?

sharkcutup
Posts: 408
Joined: Tue Mar 08, 2016 5:23 pm

Re: pocket depths

Post by sharkcutup »

VCP 8.5

If you are clearing a large area with varying depth you might want to try the Fluting tool path. I have tried several pockets with varying depths (.25" - .75") with only a .0005" clear plane. That is the best I could get otherwise an error message says - The 'rapid clearance gap' must be greater than zero (0). I do not know of any other alternative except the Fluting tool path.

The Fluting tool path is a bit more complicated to use but it can provide better results in some instances.

Sharkcutup
V-Carve Pro Tips, Gadget Tips & Videos
YouTube Channel - Sharkcutup CNC
V-Carve Pro 11.554

albers
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Joined: Sat Jun 10, 2017 10:39 am

Re: pocket depths

Post by albers »

thank you for the response. The pocket is of constant depth....the multiple depths flow from the fact that the depth of the pocket exceeds the capability of the 1/4 inch end mill, so I wanted to take the material out in two depths....
does this change your answer?

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Kayvon
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Joined: Tue Oct 21, 2014 11:46 pm

Re: pocket depths

Post by Kayvon »

I don't think the fluting toolpath applies to your situation at all.

It sounds like you're concerned that, between successive depths, the bit retracts above the top of the piece before starting the next depth. You can change how far up it retracts, giving it a low number. (I don't think a negative number is allowed here.) However, I don't know of a way to prevent it entirely.

Fortunately, the time it takes to move up and down is pretty short. If you want to make it shorter, you could increase the Z speed of the bit in question. This will also increase the plunge speed into the material, so you'll probably want to make a ramped entry into the material if you're not already doing so.

sharkcutup
Posts: 408
Joined: Tue Mar 08, 2016 5:23 pm

Re: pocket depths

Post by sharkcutup »

Okay so the fluting tool path may not be beneficial here. Just a thought from what I initially understood!

I am now assuming that you have a material thickness that is beyond the depth capabilities of your chosen end mill length and you are wanting to carve out in successive depths with said end mill to achieve the desired total depth. As Kayvon has pointed out you could give the Z 'rapid clearance' gap a low number thereby the bit will not retract as far. And I also agree that you cannot use a negative number you are only able to use anything greater than zero (0).

There may be a way to edit the tool path g-code to achieve what you want and just maybe there may be someone here that knows how to do it.

Good Luck!

Sharkcutup
V-Carve Pro Tips, Gadget Tips & Videos
YouTube Channel - Sharkcutup CNC
V-Carve Pro 11.554

albers
Posts: 13
Joined: Sat Jun 10, 2017 10:39 am

Re: pocket depths

Post by albers »

thanks to all. The minor editing of the tap file is my selected path of action....very efficient for the Shark and very efficient cycle time....

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gmm50
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Joined: Fri May 16, 2014 5:22 pm

Re: pocket depths

Post by gmm50 »

What we used to do many years ago with poorly generated assembly language code is to pass it through an optimizer.
Lots of work to get the first one running but then very easy to keep using it.
This works great in a production environment but probably not worth it for a hobby project.

I just sit here an watch the wasted motion. We're running about 80 hours a month of pure cutting time.
So soon I will be able to justify paying a high school person the $$ to create the optimizer program.

GCode file in OPTIMIZED GCode file out.
I would program it in Visual Basic and run on a Windows machine. My 2 cents
George

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