3D Machining Depth Never Correct

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RaspberryJamGuitars
Posts: 2
Joined: Fri Feb 07, 2020 12:46 am
Model of CNC Machine: AccTek

3D Machining Depth Never Correct

Post by RaspberryJamGuitars »

Help please;
VCarve Pro
So I have been learning some CAD software and can draw and export 3D models. I export in the .STL formal. These go into VCarve Pro just fine, looking just like they should, correct dimensions come over, correct orientation etc. However I cannot, regardless of all the permutations of model depth, z-plane, zero plane, vector positioning, I believe in fact, I have played with every available VCarve variable in this area and I cannot get the Z depth to where the whole depth of the model is cut out. I can do it with the VCarve clip art, but not with any object I have drawn and imported.
Any takers on a solution for me?

This is what Vectric promises on import....
First.jpg
What's not to like? The model is all as it was drawn in my CAD
Third.jpg
Same again, with the basic settings; I have varied all of these to no avail....
Second.jpg
But wait, look at the toolpath, it has a ledge, in this case it is about 4mm out of a 40 mm deep model:
Fifth.jpg
Run the simulation and there is the ledge in all its glory:
Fourth.jpg
How do I get my 40 mm in Z model to be machined at 40 mm? I have imported a number of tests and they all experience the same problem. As noted, I have tried every variation of planes, model in the material, slicing, Z heights etc to no avail.
Any takers on a solution for me. ?

SteveNelson46
Vectric Wizard
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Re: 3D Machining Depth Never Correct

Post by SteveNelson46 »

Try adding a zero plane.
Steve

gregk
Vectric Staff
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Joined: Mon Mar 05, 2018 12:34 pm
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Re: 3D Machining Depth Never Correct

Post by gregk »

If you look closer at the toolpath then you can notice that it stops when it reaches material boundaries. In order to machine your shape the tool have to go outside of your material boundaries. You need to make your material bigger, otherwise tool will not be allowed to machine whole model. Hope this make sense,

Greg K

litzluth
Vectric Craftsman
Posts: 119
Joined: Fri May 09, 2014 1:37 pm
Model of CNC Machine: Laguna IQ

Re: 3D Machining Depth Never Correct

Post by litzluth »

Have a look at this thread. I think you are having the same problem.
viewtopic.php?f=27&t=24723&p=177179&hil ... et#p177138

RaspberryJamGuitars
Posts: 2
Joined: Fri Feb 07, 2020 12:46 am
Model of CNC Machine: AccTek

Re: 3D Machining Depth Never Correct

Post by RaspberryJamGuitars »

Thanks to all who have answered:

I have always used a zero plane and played with where it is located;
I have increased the vector offset around the model to no apparent avail;
However, although I have played with various material depth settings, I am not sure I have tried to "pretend" the model is thicker than it actually is, I will run off and try that now.

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Adrian
Vectric Archimage
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Location: Surrey, UK

Re: 3D Machining Depth Never Correct

Post by Adrian »

I created a model like yours and had the same issue. I added a zero plane and recalculated the toolpaths and it was fine.

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adze_cnc
Vectric Apprentice
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Joined: Sat Jul 27, 2013 10:08 pm
Model of CNC Machine: AXYZ 4008
Location: Vancouver, BC, Canada

Re: 3D Machining Depth Never Correct

Post by adze_cnc »

Adrian,

Was your model "bounding box" XY dimensions the same as the job size XY dimensions when you added the zero-plane?

I also made a test model like this then added a zero plane but since the base model size and the job size were the same the zero-plane didn't matter as it was that same size. I just can't really see how adding zero-plane can help on a convex model unless the job size is larger than the model size so that the zero plane extends the model. Then you can use the "model boundary" setting in the 3D finish path.

My general approach to any of these type models is to create a 3D finish path with a "selected vector" which is the profile of the 3D model. I then use the boundary offset to force the bit to cut to the bottom of the vertical curve plane. I just need to plan things so that the finish path doesn't "go over the edge" on the vertical ends--usually making the boundary vector shorter by the boundary offset on those ends.

Steven

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