Pocket first pass to deep

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Pocket first pass to deep

Postby Jim Krager » Fri May 22, 2015 12:13 pm

I set all of my passes to 0.0625 inches, but the first pass plunges to 0.25 inches can anyone see a reason my crv file is doing this?

peace sign.crv
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Re: Pocket first pass to deep

Postby 4DThinker » Fri May 22, 2015 1:30 pm

There doesn't seem to be anything wrong with your tool paths.

If you used a touch plate to set z=0 when cutting this file I'd check that what the controller has set for the touchplate thickness is actually how thick your touchplate is.
Then I'd double check that your bit is tight in the collet. Upcut spiral bits can pull themselves down as they cut if loose in the router collet. Gravity can pull most other bits down as well.

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Re: Pocket first pass to deep

Postby SnaykeByte » Wed Sep 30, 2015 8:57 pm

I'm having the exact same problem for the second time now and I just set Z with a piece of paper. Ruined two pieces of stock so far.
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Re: Pocket first pass to deep

Postby Rando » Sun Oct 04, 2015 2:31 am

There's a 20-mil offset (Grrrr....) that is apparently buried inside the controller.

When I touch-off, I use "no" touchplate, but instead use an 0.020" piece of sheet metal. That seems to give a very accurate height, as long as there is minimal cupping of that sheet metal.

Before I did that, when I was touching off directly from the (Aluminum) stock, it would always bite 20 mils PLUS the first layer height.

In cases of non-metallic stock, I'll subtract 20 mils from the number the controller calls it's location after the touchoff. So, if I start at a random distance up, 1.53 inches, and then touch off using the 0.375" touch plate, it will go back to 1.53 inches relative to the material height. Except guess what...that 1.53 it claims it's from the surface? Yeah, it's **really** only 1.33 inches from the surface. So, using the Set button I'll SUBTRACT 0.020 from whatever number it has for Z. That way when it plunges to zero to start the cut, it's actually at zero, not 20 mils inside the material.

Hope that helps; it sure has fixed my first-layer problems.

Regards,

Thom Randolph
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Re: Pocket first pass to deep

Postby meb » Mon Nov 02, 2015 4:47 pm

Make sure you are using the right parameters. Check your post processor you save your tap file with check bits used check units in the control panel to make sure you are using inches or millimeters, don't mixed them because this could cause the problem you are having.

Also if you have updated post processors that could be the problem.

One more thing, why are you pocketing the inside areas, just include the vectors in the cutout and save 2/3 of the total time to cut the project. Not to mention doing away with the tool change and ware and tare on the bits and machine.

There is another post about pocketing problems they updated their VCarve 8 software, this may be the issue.
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