# Cnc router v groove help



## KennebellGT (Jul 10, 2015)

We are having an issue while attempting to v groove corian with our cnc machine. We are using alphacam 2014 R1, using a 90 degree single blade insert with a v groove blade. The problem were having is after the material is v grooved the bit leaves behind burs and burns at the bottom of the v groove. which means if we glue our edge detail on you'd see a white line where the material was burned. Is there a method to leaving no burns/burs behind and have a clean cut v groove? Thanks, and happy to be a part of this forum!


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## 4DThinker (Feb 16, 2014)

What feed speed are you using? Typically burns are cause by friction. The center of the bit spins but if it isn't moving forward quickly it'll heat up the bottom of the slot and cause the burns you are seeing. Creep up the speed until you don't see any burning. Dull bits can also contribute, so a new sharp bit will help.


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## KennebellGT (Jul 10, 2015)

What feed speed would you recommend? I won't be back to the cnc until Friday. Thank you for the quick reply.


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## 4DThinker (Feb 16, 2014)

KennebellGT said:


> What feed speed would you recommend? I won't be back to the cnc until Friday. Thank you for the quick reply.


Depends on how deep each pass is. Just set it 20% or so faster than you have it now and do a test cut.


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## KennebellGT (Jul 10, 2015)

One thing I had noticed is when I sped it up, it would chatter the v groove, and going to slow would like you said cause it to burn the material leaving a white burn line.


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## 4DThinker (Feb 16, 2014)

You didn't say what kind of CNC you have. Chatter can be from flex in the system, a dull bit, or both. I'm going to suggest a new bit. Minerals in the material can dull a bit quickly.


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## KennebellGT (Jul 10, 2015)

Sorry for the late reply we have a scm pratix s


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## subtleaccents (Nov 5, 2011)

I was a Dupont CFI for 30 years before retiring. I have a Techno LC 4896. It is considered a medium duty machine. I did V Groves with it.
All my vanity tops were cut on it. (Bowl hole, bowl alignment marks, faucet holes, back splash and buildup when doing a sandwich)
I did have small chatter marks when I first tried doing the V grove. I eliminated that by taking a .010 finish cut after 2 rough cuts @ .230 each. Those numbers could vary depending on the factory thickness of the individual sheet stock. I checked each piece to get an average before cutting. I tried to leave .005 uncut so I didn't cut the tape. Never had seam show using this method.
As mentioned by others, you do need a sharp cutter. Corian is abrasive as you probably already know. I found what is dull for cutting Corian is still fairly sharp for soft woods.


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## KennebellGT (Jul 10, 2015)

Thank you, I will give it a shot when I have the free time. What feed speeds would you recommend?


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