DIY Three Axis Zero Plate?

[dana_swift]

Here is the thread where the build-it-yourself 3 axis topic got introduced to the sweat fitting method. I posted several photos of my method in the post.

http://www.talkshopbot.com/forum/showthread.php?13534-Setting-X-Y-Zero

I came up with the sweat fitting method on my own, there may have been other people who came up with the same idea prior to me, its pretty obvious. Its still the way I use to position fixtures, the main table, etc. I'm glad the idea has spread from whatever source it may have come from.

Also I have a custom superzero made out of aluminum. The sweat fitting method is so cheap, reliable, and flexible that I rarely use the machined part.

D

[steve_g]

Here’s a typical jig setup for me… Having a super Z cap on the jig means I can locate the jig anywhere on the router bed (parallel to the X&Y axis) and quickly be set up and running…
SG

[rb99]

Here is the thread where the build-it-yourself 3 axis topic got introduced to the sweat fitting method. I posted several photos of my method in the post.

http://www.talkshopbot.com/forum/showthread.php?13534-Setting-X-Y-Zero

I came up with the sweat fitting method on my own, there may have been other people who came up with the same idea prior to me, its pretty obvious. Its still the way I use to position fixtures, the main table, etc. I'm glad the idea has spread from whatever source it may have come from.

Also I have a custom superzero made out of aluminum. The sweat fitting method is so cheap, reliable, and flexible that I rarely use the machined part.

D

How accurate is the copper sweat fitting? How perfectly round?

How do you measure the thickness for Z zero accurately?

Without it being inset into a thin block like the Super Zero how do you zero the X and Y with it?

[jerry_stanek]

The sweat fitting doesn't need to be round it could be square the bit touches each side and the the measurement it divided.

You tell the software the thickness of the zero plate

Without the super z you use the table limit switches.You would do a C3 command and the gantry moves to the X limit and backs off the offset that you have set in the SB setup software then it does the same for the Y. Every time you run the C3 it should go to the same spot on the table.

[steve_g]

RB…
The beauty of the super Z is that its accuracy isn’t dependent on the precision of the copper cap… Mathematically, you’re measuring the length of the cord of an arc, going to its mid-point and repeating the measurement at a right angle to the first… Theoretically, the mid-point of the second arc is the center of the circle. If the cap isn’t perfectly round, running the routine the first time gets you close and running it the second time assures that the cords you’re measuring are the same ones every time, assuring repeatability.
In my case, I’ll first embed the cap in a fixture blank, zero with it and then build the fixture from that setting.
There are several ways to measure the cap thickness if you’re using the super-z in a manner that requires you to know it… One method is to zero a bit to the bed, next, with the z-zeroing wire clamp attached to the bit, lower the bit inside the cap SLOWLY using the “fixed” setting at only a few thou per click when you’re getting close, when the “light” on the channel the z-zero is hooked up to lights up read the DRO for your thickness.
Hope this helps!
SG