Another Touch Probe Thread

[activereality]

As usual is usual around here, there seems to be one person really getting down and dirty and making posts everyday haha. Guess thats mean right now.

This project will be for a touch probe - for the z and x/y. I have seen a few made this way (so i don't know who to cite for a true attribution haha). This is roughed out to be 1/2" x 2" x 2". With a cut out on the bottom to fit over a corner or outer profile of a circle.

I see some probes are cut all the way through, for the diameter on the bottom section. Is there a reason/purpose for this? Other than visual at least. 

I also am wondering if i should face the bottom and top of the plate. 2 reasons for this:
1. Gives an actual flat surface for the plate to be touched off of (on top) and also reduces the dimension to slightly less than .5". 
2. If i ever do need to put this on something that is .5" +/- .1" or so, it should still be able to be used to find a corner.

I am also wondering if i should do a pass on the sides - to help clean up any inconsistencies on the sides - or just measure them and use that value in my probe set up.

pic for fun - and to see if i can link from imgur haha.
 
<blockquote class="imgur-embed-pub" lang="en" data-id="a/pG7A0aI" ><a href="//imgur.com/a/pG7A0aI">Touch Plate</a></blockquote><script async src="//s.imgur.com/min/embed.js" charset="utf-8"></script>


imgur.com/a/pG7A0aI

Probe



guess i am going to have to research how to link photos again - without downloading them into the actual post.

[jms]

I made mine out of .250" alum so I can use it on .250 material. recess I made .126" I put mine on my milling machine hit all edges top and bottom so that it was all square and truly flat before cutting the recess. I then wrote a couple of macros in 2 of the custom buttons in bcnc. 1 button is just for Z, the other for x,y and z.
hope this helps you, if you want the gcode for macro i wrote , let me know. Although, i did post it a cpl months ago in these forums.

[activereality]

Thanks, JMS, Yeah I think I saw that you had posted the macro - I'll take a look at it.

Is the .250" aluminum heavy enough that it does not move when the machine 'finds zero? That is why I was thinking of using the 'thicker' piece. So it would be a bit heavier.

[jms]

made a mistake, its .375 " thick and recess leaves me with .242".Mine doesn't move, but mine is 3" x 3" and recess leaves me with .242 " that hangs over x and y

[activereality]

Gotcha. I get it now. Food for thought. I was thinking 2x2. But might aim for 3x3. Hmm.

[jms]

i did not make a hole at "0" I only put a tiny dot with a sharpie for close reference when only using Z probe.

[activereality]

I think I might make a "poor man's" Z probe with some small pieces of aluminum, from another project. They are offcuts of a 2"x2" angle aluminum.

I see the value in having a probe just for the Z, for when I just need to get a z-axis set - like after a tool change.

I am going to try and see if I can face the material (top and bottom faces), by about .01", for a more consistent surface and depth. Then try and bore a small hole into a face (no angle) and see if I can solder a wire into it - to use that as the continuity line.

My spindle power supply is using the same power strip as the power supply for the CK1 Main Board. So I _might not_ need to run a separate lead to the spindle, although I will prep a line just for that.

I already have an enclosure for the CK1 mostly made (hastily thrown together for moving from Florida to Texas haha) - so will eventually be extending the wiring so I can run the electronics from the outside. When I do this I will be making some new electronics boxes - need something to contain the Spindle Power supply and also need a small box for the spindle speed controller board and knob.

[Bruce]

The circle through the end of the probe lets you see the corner of the workpiece. You can also set the zero by writing a routine to probe three sides of the inside circle, calculate the center point and set the zero that way. Not many people use this method though.