Help - new to CNC

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zeighty
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Help - new to CNC

Post by zeighty »

I am a new to CNC and vCarve. I am practicing using Pine. I don’t think I would use this for anything finished.
Here’s my dilemma: i’m having trouble determining how deep to go when v-carving. I did a practice run today and certain parts of letters are not deep at all; barely scratching the surface. For example the horizontal part of an H is no deeper than I could have made with a ball point pen. I was using a true type font script.
Machine is a next wave automation Piranha XL. The bit I was using was a quarter inch shank, three eights inch diameter, 90° v carve.
Any help would be most appreciated. I need to get past this learning curve so I can be productive. Thanks again!

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Mike-S
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Re: Help - new to CNC

Post by Mike-S »

i’m having trouble determining how deep to go when v-carving
You don't really need to determine anything as the depth is determined by the spacing between the vectors and the angle of the V-bit. The bit "rides" on the two vectors and goes deeper when they are spaced further apart. It sounds like your H has closely spaced vectors.

Also, your pine surface needs to be exactly parallel to the X-Y plane or you will get uneven V-carving.

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mtylerfl
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Re: Help - new to CNC

Post by mtylerfl »

zeighty wrote:...I need to get past this learning curve so I can be productive. Thanks again!
Hi. I think you will find the following Video Tutorial helpful. It should answer some questions about v-carving that you may not have thought of to ask yet! Here is the link:

http://support.vectric.com/tutorials/V9 ... ll&time=31
Michael Tyler

facebook.com/carvebuddy

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Leo
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Re: Help - new to CNC

Post by Leo »

I will also encourage you to watch the video that Michael referenced above. It will answer a lot of questions.

Just a couple of points though

1) the smaller the text the narrower the space between lines.

2) You will get better results on smaller text with a more acutely angled tool like a 60* or even a 30*

3) Larger text - 5" or 15" till get better results with a blunter angled tool like a 120*

The more acute the angle, the deeper the tool will cut.
Imagine the Possibilities of a Creative mind, combined with the functionality of CNC

zeighty
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Re: Help - new to CNC

Post by zeighty »

Thank you all for the feedback and direction. It really helped me understand why my selected typeface behaved as it did. I have watched many of the tutorial videos, but had not gotten to this one. It was most enlightening.
Thanks again. I am sure I will be back, hopefully with more challenging questions.
This software is really impressive.

LittleGreyMan
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Re: Help - new to CNC

Post by LittleGreyMan »

As some carvings may be very shallow (when the distance between vectors is very small), you also need a perfectly flat material and an accurate Z0.

You may have to surface the material on the machine to perfectly control these parameters.
Best regards

Didier

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zeighty
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Re: Help - new to CNC

Post by zeighty »

One more thing that’s bugging me... tool marks on the bottom when using a pocket tool path. I see them mostly when using a 1/8” spiral up cut end mill. I think this is probably a case of selecting the correct bit for the wood/job.

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Leo
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Re: Help - new to CNC

Post by Leo »

Having the spindle absolutely perpendicular to the machine bed is extremely important.

If the spindle is not perpendicular, then the flat end of the cutter will not be perfectly parallel and one corner will dig in more, leaving lines

Even if - you get the spindle perfectly perpendicular, you will get spirals - just the nature of the process.
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Jozua
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Re: Help - new to CNC

Post by Jozua »

zeighty wrote: I see them mostly when using a 1/8” spiral up cut end mill. I think this is probably a case of selecting the correct bit for the wood/job.
What step-over did you specify for the 1/8* clearing bit?

Joz

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scottp55
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Re: Help - new to CNC

Post by scottp55 »

Once your Z is plumb,
For a .125" bit for small pockets, it doesn't get much better than Drillman1's downcut;
https://www.ebay.com/itm/1-8-1250-CARBI ... 0005.m1851
Downcuts give me a better pocket bottom than upcuts in hardwoods.
For bigger(biz card and up size) I like the Centurion FEM downcuts;
http://www.centuriontools.com/router-bi ... =Downshear

Playing with the pass depth so that the last pass is about .01-.02" helps a LOT.
Sometimes just running the toolpath twice helps (or nudging the Z down a hair), as there's no side pressure on the bit.
On less rigid machines, lighten up on the pass depth....I HATE sanding small pocket bottoms! :)
scott
Attachments
KYOCERA .125 2F DOWN.jpg
M POCKET TEST CENTURION.25FEMDOWN 7.jpg
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zeighty
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Re: Help - new to CNC

Post by zeighty »

To all, thanks for the advice. I am traveling on business. Once I return I’ll check the step over and also consider the suggested bits.
Scottp55 your second example is great. I have not attempted anything that small or detailed. Soon I hope.

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