Maybe not more accurate, but… LASERS!! 
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Yea, didn’t get as far as reading instructions, lol. Couldn’t sleep last night and sat up thinking about cnc stuff…
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Happens to me a lot…
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No real benefit over a v-bit i guess other than not having to mess with the z axis to bring the bit to the surface.
I wasn’t thinking about using an exact location to start cuts, more of having a precise location to calibrate to, and a few others to check accuracy. We deal with systems that involve miles of line, flexing crane booms, soft attachments seating, line elongation, humidity changes, temperature changes, etc. which all contribute to inaccuracies. We typically find a “home” in the space (i.e., a nail driven into the ground or a paint mark on concrete, etc), and if we notice the system is beginning to lose accuracy, we “re-zero” (not necessarily 0,0, but known coordinates) at the home position. This procedure or something similar may already be in place, and forgive me if it is.
So, what I was driving at, was “zero” at a known location. Drive the sled to another known location (maybe towards the extremes of the space), and check for accuracy. Does that make any sense?
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Can you use a 12mm cheap module and a bit of masking tape to make it fit in the 1/2" collet?
If you want to be serious you can use a pair of laser line modules attached to the sled and aimed so they cross in the center of the bit, and it’ll stay crossed at the same point if you increase the distance from the sled to the workpiece. Not really necessary on a maslow, but, you know, two lasers!
Sounds like a normal machinist thing. Don’t you need two points to handle inadvertent rotation?
I call it Point of Origin. I suppose you can abbreviate that to POO. In the software for the Shapoko3 the user can choose several predefined areas. Upper left, Upper right, Lower left & I think workspace center. On my laser it is Upper Left as you would read a book. My first 3D printer had no end stops on the revision I started into so it was always center of the work space and distance of travel divided by 2 - mins a safety margin. On the Maslow after much thought I prefer the Center of the Workspace. I have a hole for using a pencil in my sled that i use to make a home point. I plan at some point to add a laser on an offset for fun because you know Lasers!
I will have a index mark to use the laser offset from the center for working on new sheets of material and defining home.
However the work flow of the Maslow calls for redefining Home on fly.
“Home is where you hang your hat”
A defined POO is important for parking your work or multiprosses parts with indexing pins. I plan to use dowels as indexing pins and this is where the laser will come in to find a known starting location. This will only work if the machine is accurate enough. with this you can flip 2 sided parts.
@bar and I had a discussion on mounting pins / fasteners.
People have shown concern about using plastic nails instead of screws, I will choose to use dowels because they are cheap and plentiful. Bar pointed out he has plowed through screws with no problem for his router.
Here is an example of using index pins to make 2 sides parts -
Depending on your work flow a known home pint of origin is or isn’t important.
Thank you
see the triangular calibration topic.
we have enough variables that it’s more than just checking two points.
but with the newer, simplified calibration approach you could quickly check the
calibration, you need to check the distance between the motors and then two
points (home and one other)
I would do this with a V bit, drill a couple tapered holes in the frame with the
bit, and then you can tell how close you are to being exactly there again.
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guy’s this V-bit idea really must get a spot in the wiki.
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