Radial Vcarve texture on circular box lid. Updated spin-off!

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Hi guys.
Probably you all know how to do this, even then I thought I could post it to find out if there is an easier way.
I drew a circle and then I made a narrow triangle of 5º that later on I copied 36 times at full 360º. Then I chose a 12º V bit with a Vcarve path. The triangles were longer than the radius of the circle so that they would reach the edge of the circle once it was cut afterwards. I also made a smal circular pocket to prevent messing too much the center of the box lid
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Well, deepening into the posibilities of this approach, I thought I could make a box with a saw toothed seam between the lid and the bottom.
Here you can see the result, the box is neither sanded nor finished the top surface is varnished because I used a scrap that it was.

IMG_6668.JPG
Problem one: The tips of some of the teeth were flat, which makes me think that either my spoil board is not horizontal respect the gantry, or that the thickness of the wood piece was not even all over the piece.
Problem two: I don't know why my cnc machine is making those small circular stairs at the center of the pocket, I used the same G_Code file for both pieces and it didn't make them in the oak one.
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Problem three: Some of the teeth chipped away rendering the joint not so good looking. So I guess it is a matter of wood choice together with the order in which the different paths are milled, the speed and feed rate, as well as the grain direction that the bit encounters when milling.
IMG_6671.JPG

I have not seen videos on youtube making this sort of joint in boxes, which doesn't mean that I am the first one. Probably I am rediscovering the wheel and they are not there due to the not so good results at the end.

Anyway, any suggestions from more experienced CNC members to solve the mentioned drawbacks will be welcomed.
 
Toni are you using a climbing cut?
Hi Jay. I’m using a climbing cut on the saw teeth and conventional on the pocket and profile cut. Do not ask me why, because I still don’t know how much difference they make when milling. It is just that I thought it would be good to do so.
 
Well, deepening into the posibilities of this approach, I thought I could make a box with a saw toothed seam between the lid and the bottom.
Here you can see the result, the box is neither sanded nor finished the top surface is varnished because I used a scrap that it was.


Problem one: The tips of some of the teeth were flat, which makes me think that either my spoil board is not horizontal respect the gantry, or that the thickness of the wood piece was not even all over the piece.
Yes, it could be that the machine bed it not flat or not parallel to the gantry axis in X and in Y. You can fix that by attaching a "sacrificial" table surface and then machining that flat with a "pocketing" toolpath, cutting as little as possible - maybe 1 mm

Problem two: I don't know why my cnc machine is making those small circular stairs at the center of the pocket, I used the same G_Code file for both pieces and it didn't make them in the oak one.
Not sure about that one

Problem three: Some of the teeth chipped away rendering the joint not so good looking. So I guess it is a matter of wood choice together with the order in which the different paths are milled, the speed and feed rate, as well as the grain direction that the bit encounters when milling.
I will blame that one mostly on wood species. Some woods just chipout more than others. Oak is notorious for that. Hard Maple is really good. DENSE close grain wood is best. As to feed and speed - CHIPLOAD - is the most important factor to gain an understanding of how that matters.


I have not seen videos on youtube making this sort of joint in boxes, which doesn't mean that I am the first one. Probably I am rediscovering the wheel and they are not there due to the not so good results at the end.
You do certainly do push the envelope though I have watched a lot of seriously talented folk doing some really intrecate stuff.

Anyway, any suggestions from more experienced CNC members to solve the mentioned drawbacks will be welcomed.
 
Hi Jay. I’m using a climbing cut on the saw teeth and conventional on the pocket and profile cut. Do not ask me why, because I still don’t know how much difference they make when milling. It is just that I thought it would be good to do so.

I use climb cut as much as possible.

On the "V" cut it doesn't really matter, as the cut is climb on one side of the cutter and conventional on the other side, no matter what you select.
 
A "V" cut with the tip of the bit cutting ON the vector is always going to cut Climb and Conventional. It's just the nature of the beast. Cutting off center will not make a pointy botton of the "V" cut.

Same thing on a slot where the slot and bit are the same dimension.

I have not found making several lighter depth cuts to help with chipping Oak. Oak is just going to chip out because the small cross section is weak because of the not se dense open grain.

I can get a really nice "V" cut in hard maple, but not oak.
 
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