Hi all. I’ve frequently had issues with bits going too deep on the initial plunge. I use both the BitSetter and BitZero.
I’m curious about the BitSetter button – when measuring the bit, the bit taps the button twice. The first tap pushes the button almost all the way down, while the second tap pushes the button about halfway. Is this expected behavior? I’m wondering if the second tap should NOT be a plunge but just a light touch, a la the BitZero’s Z indexing. The little light next to my BitSetter never comes on. Not sure if that means anything.
Yes, the machine probes twice, since the second time it has a better idea of the relative position of things and can do it more slowly which will be more precise/accurate.
Hi Will. What I’m trying to understand is: should the second probe push the button down halfway, or just lightly touch it (detecting metal like the BitZero)? And when (if ever) should the BitSetter’s LED light up? Thanks
I found an old video from Winston that shows the BitSetter doing a full press followed by a half-press, which answers my question about the second probe. Thanks
With the Bit Zero we place the bit at a height just above the plate and then it does a slow probe until it makes electrical contact between the grounded bit and the touch plate. It just touches.
With the Bit Setter it does not know how close it is to the button so it first has to do a fast probe to find the button and at that speed it passes the internal trigger point of the spring loaded button. Over shoots it, compressing the spring. ( “Full depression” as you mentioned ) It then retracts a bit and re-probes at a slower speed for an accurate reading. (“Half depression” ). This means the Bit Setter has a different trigger point requirement then the Bit Zero. The spring loaded button trigger mechanism allows for high speed over shooting verse just a simple slow speed contact.
Also the bitsetter and bit zero use different methods to detect the bit position. As was mentioned above, the bit zero uses electrical contact between the bit and plate to determine position. The bitsetter uses a proximity switch inside the housing. It is actually detecting the movement of the aluminum button in reference to that proximity switch inside (like the limit switches on your x, y, and z axes. The machine moves quickly to get a rough location of the bit against the limit switch (aka proximity switch) in the bitsetter, then tries again slower to get a more precise measurement. It’s on that second try that it will often not go as deep because it doesn’t overshoot the same as the initial higher speed bump. You’ll notice similar behavior with the limit switches for x, y, and z axes when you initialize your machine. So, it is normal to see different depths for each of the two bumps.
Since you mention you are using your Bit zero and sometimes getting the wrong initial depth of cut, double check that you are probing correctly. If you are doing a z only probe, the bit zero must be sitting fully on top of your material with the x-y alignment lips sitting on top as opposed to hanging off the edge like you are doing a full corner probe. If you do a z probe and have those lips hanging off you will end up with the machine thinking the surface of your material is lower than it is by the thickness of those lips (~.1”). Hopefully that helps and makes sense.
