Help With 3 Axis Zero Plate

[rb99]

I am looking for a way to zero the 3 axis on my older shopbot with a 4g controller. I remember there were aluminum plates with a recessed hole that the bit goes into the hole and touches 3 sides and then the bottom. Are these still the way to go? I see SB sells a plate of some type but it looks like it is for depth alone?

Thanks for the help!

[curtiss]

Not quite sure what you want to do, but one way is to use two hold-downs to secure the work piece / say on the upper left side. A third clamp holds down the Zero plate on top of the work piece / with the aluminum edges parallel to the work piece edges.

Zero to the top or the plate, and then drive/ nudge the Bot around with a 1/4 inch bit so you touch the edges of the plate from the x & y directions .... when the bit touches the edge of the plate set the proper read out to -.125

The 0,0 position should then be over the lower right corner of the material. Remove the plate and re-clamp as needed.

[rb99]

Not quite sure what you want to do, but one way is to use two hold-downs to secure the work piece / say on the upper left side. A third clamp holds down the Zero plate on top of the work piece / with the aluminum edges parallel to the work piece edges.

Zero to the top or the plate, and then drive/ nudge the Bot around with a 1/4 inch bit so you touch the edges of the plate from the x & y directions .... when the bit touches the edge of the plate set the proper read out to -.125

The 0,0 position should then be over the lower right corner of the material. Remove the plate and re-clamp as needed.

What I want to do is have a plate or something that allows me to quickly zero the X Y and Z axis'.

I am not sure which plate you are talking about. Since starting this thread I found the one I saw a few years ago. Then there is the new one. Or new to me.

Old one. It does 3 axis zeroing:

https://store.shopbottools.com/colle...ant=7825832513








New Zero Plate. It appears to only do Z axis zeroing:

https://store.shopbottools.com/produ...nt=24782112519




Are there any other 3 axis plates available? I remember some with a hole in the aluminum plate and the bit touches 2 or 3 sides and then it knows where the center is. As I remember there also needs to be a software routine as well. I have the 4G controller, but an old old bot.

[scottp55]

And then there's the old do it yourself methods(I haven't used but saved pics ) for 3 axis Zeroing, but you'd need to write a new Zeroing routine.
These were mainly for Zeroing a fixture,but maybe not to hard to rig a spot on your board for?

[tom burke]

The 3-axis zero plate isn't "old" and the pressure-sensitive Z-zero plate "new"—they have different functions, and I use both. The 3-axis plate can be plugged into the same connector on the gantry that the normal Z-zero plate uses, and placed where it is needed for 1-, 2-, or 3-axis zeroing (the software routines are included in SB3). The pressure-sensitive Z-zero plate can also be plugged into that connector, but it makes much more sense to order it with the optional extension cable and permanently mount it somewhere on the table where the spindle can reach it but it won't be in the way of normal operations. It is then wired directly into the control box. The point of the pressure-sensitive plate is that it allows you to use a routine that automatically adjusts the Z-zero after a bit change. That's convenient for normal work, and almost essential if you have an automatic tool changer (which I don't).

[coryatjohn]

I gave up on the automatic zeroing years ago after the second time I forgot to remove the clamp from the spindle. I switched to a much more intuitive method that uses a dial indicator.

s-l1600 (1).jpg

I've always been concerned about "automatic" systems as they can automatically destroy things just as quickly as they can save effort. I'd rather know where the bit is than trust the machine. Call me a crazy old coot but there it is.\

To do an X-Y zero, I have a 1/8" hole drilled in the table at X=1, Y=1 and use a 1/8" solid rod for doing that. My machine never loses position so I only have to change the XY if I change the axis for some reason. I rarely do that anymore.

[srwtlc]

This should get you started. You can modify to suit your needs.

https://1drv.ms/u/s!AsPqyLrhnhkRgzmU...NNVGq?e=dnJMAO

[steve_g]

Well… it took some hunting and digging, but here’s a jig I used to use.
The copper pipe cap is embedded in the jig. And the jig can be located anywhere on the table. The bit is placed somewhere inside the cap, the zeroing routine touches x left and right, y top and bottom and finally finds the bottom of the cap.
A very accurate and inexpensive X,Y,Z zeroing jig. Cheap enough that every jig can have one built into it!

SG

[rb99]

If forgetting the clamp is an issue, perhaps making it with a break-a-way using magnets would help?

[curtiss]

Usually, the x-y 0,0 is just set wherever you want it to be using the VA command.

One other method is to set the bit say an 1/8 inch above the material / near the corner you want to become 0,0

Use a digital caliper depth gauge to measure from the edge of the material to the edge of the bit and add 1/2 the diameter of the bit and that becomes the value for that axis

Repeat from the other direction and set those values with the VA command.