Not having much luck with PVC! Need some help?!

Gallery for images of work cut using PhotoVCarve
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t82inker
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Not having much luck with PVC! Need some help?!

Post by t82inker »

I've been attempting using all sorts of settings I see on this forum different bits, different depths, 100% up to 180% for lines and don't see where you adjust stepover. Clearcoated wood to allow me to put black in the areas it cuts out....and it cuts out almost everthing....some deeper. Tried melamine which I thought would be awesome and it takes off the top surface also......What am I doing wrong???

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Xxray
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Re: Not having much luck with PVC! Need some help?!

Post by Xxray »

You adjust line spacing - Don't use the slider, enter a number like 15-20. The lower the number, the more lines, more detail, more time.
Note also it is common to check "invert light/dark areas" else the image machines like a negative.
Doug

Bob Reda
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Re: Not having much luck with PVC! Need some help?!

Post by Bob Reda »

If it is removing everything it is the depth of cut you may having an issue with. I normally use around 125% line spacing and a depth of cut of .035. I also use a .25 60 degree v bit or even an engraving bit. Anything bigger will also remove a lot more material. This is for a normal pvc. Some have been using ballnose with an 8 percent stepover and get more of a 3d effect. If this for lithophane , then its completely different. If you are using setting close to what I use and it is still taking off too much, the z axix on your machine is off.

Bob

t82inker
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Re: Not having much luck with PVC! Need some help?!

Post by t82inker »

My settings are 120% and .032 depth of cut with an engraving bit .250 Dia. with an 18 degree tip .002 point and it skims off the top layer of wood along with carving the deeper spots.

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Lionel
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Re: Not having much luck with PVC! Need some help?!

Post by Lionel »

Not sure if you still need help but here is my 2 cents anyway. My cnc uses a small disc to set the zero or top of material. Whenever I changeout a bit or move the material around I need to re-zero otherwise things will not work out very well. I've had my CNC for about 4 months now and one of the very first things I had to do was flatten the surface. I'm not sure if you know what that is but it is a process where you create a rectangle the size of your maximum cutting area and use a large surfacing bit to peel off about 0.005 to 0.010" at a time. You may have to run this a few times to get the surface true with the cutter. Also the melamine layer is very thin probably only 0.002" which is not a lot. As a temporary test try using a thin spacer when setting your zero, this will fool the cutter.
This is all I have, hope it helps

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