I’ve been using my 90 degree bit experimenting with some detailed maple leafs. I want to make the veins in the leaf detailed and my testing has only been hit/miss on this.
When choosing the depth in the past I’ve been able to enter a depth that is a little deeper than it needs too because in my testing the system was smart enough to know if it goes too deep the lines would be too fat so it would only go as deep as it needed to get the detail.
However, last night I ran some test carves with the detail depth set to 1/4" and I just got a bunch of fat lines. As far as I can tell I didn’t change any settings in my carving, but it simply started acting up and going too deep.
I did verify I have my material securely clamped and flat (I just use screws instead of clamps), but it seems to be going too deep.
Has anyone else encountered this? You can see from the picture, the one on the left is what I’m after and has been working fine for me, but just last night I began getting results like on the right.
I know most people will tell me to lighten the depth on the detail carve, but I did do that in my testing last night and it didn’t really help. It’s like it wants to carve everything on the same depth whereas it used to raise and fall appropriately when it got to the edges to make nice crisp ends.
Presumably, the V-Bit Z-Zero was set…?
Did you check to make sure the Z-Probe height is set correctly?
Brandon R. Parker
Yeah, I went through the standard probing process with the puck and I did it directly on the material to be carved.
Is there some additional z-zero process you’re referring to?
I don’t know what you mean when you say that your machine was “smart enough to know not to go too deep”. I have never seen a CNC machine that is smart at all. They simply do what they are told.
Anyway, I’ll move along to things that you can do something about. You are obviously using two different bits - a 90 degree v-bit to carve the veins, and a straight bit to cut out the maple leaf shape. My first suggestion to you would be to use a smaller v-bit. I use the FoxAlien 30 degree v-bit (pyramid or offset if you prefer), and have been pretty happy with the detail I can get out of it and some very fine lines. A 60 or 90 gets wide very quickly with depth and makes those fat lines you are talking about.
The second suggestion I have is that you must recalibrate your z-zero after you change bits. I personally recalibrate (or at least check) my z-zero before every carve, even if I’m just doing the same carve over again. I also use UGS to move around to different parts of the carve and check my z-zero at multiple points (with the spindle off) to make sure that the piece is not warped or uneven, which I have found to be the case several times, and it absolutely will show in the end.
I do not use a z-probe. I use a small piece of newspaper and I lower the bit until the paper won’t move any more, and that is my zero. Then as I said, I will raise my bit 5mm and move the bit around to different points of the carve (at least four) and using my newspaper again lower the bit that 5mm, and if the paper moves, I need to set my z-zero at the lowest point, or I need to level the workpiece or use another one. I have seen that a minor difference of even 0.2mm can be noticed and can potentially ruin a carve.
I really think a 30 degree bit would make a huge difference for you. Even a 60 would be better, but you will still get fat lines fairly quickly with 1/4" of depth. I would probably do a detail like that at not more than 3mm, which is a little less than 1/8".
If you are using a probe, that is as good as you will get.
Has the tip of the V-Bit been worn down?
Brandon R. Parker