Z plate

[woodworx]

I decided to mount a carriage bolt (adjustable) down near my home position. I just set it around -1 on the X axis. I would like to set it up so I can zero all bits on this bolt. Any one have a custom file written for this type of action so I can just hit C4 with my new bit and have it go to the correct position and zero my Z. Also, some parts will require zeroing from the material top. Can I just run an extra wire and ground to my bolt so I can keep my z-plate in case I need it?

[Gary Campbell]

Justin...
Open a new file in the editor, name it "Custom4.sbc" and save it to C:\SbParts\Custom.

Put this in the file:

JZ, &safe_Z
J2, (your bolt X position), (your bolt Y position)
FP, c:\SbParts\zzero.sbp
END

You need to make sure the bolt is insulated from ground and run a wire from INPUT 1 on the control panel to it. Or you can add something like a banana post to the zero plate wire as I did to use the plate or other zeroing fixtures.
Heres a pic:

7684
Gary

[myxpykalix]

Let me ask a couple of questions that might be dumb.
What is the point of mounting a bolt with some arbitrary height to it that you would set your Z height to? That seems to me would always be different than your table or material height.

Is the reasoning that your material would cover all the table and you need to Re Z to the table after toolchanges but don't have a place to Re z to?

If that is the case then I would make this suggestion so you could use it in a multipurpose way.
Take a round bar with a flat end that would be your Z'ing surface. Make a round holder similar to the router holder on your carrige, something that you can screw a allen bolt into that holds the bar with a set screw that would allow you to move the bar up or down.

Now take a "square" lay it on the table and across to your round bar and raise the round bar to meet the Square and you have a table height Z setting outside the parameters of the table and material.
If you need to Zero to the top of the material but will be cutting it away and lose that measurement but need to make a tool change then prior to cutting material run your square from top of material over, move your round bar up to meet it, lock it off and you have a constant material height Z outside of the material.

You don't need to figure out offsets and other things that might mess you up.

[woodworx]

going to put the bolt at table height. I think that is the answer to the question. Yes otherwise it would seem silly.

[jerry_stanek]

use aluminum rod so if you hit it by accident you won't break your bit and you can machine it to table height.

[nat_wheatley]

Justin,

Ed Lang has an article on this:

http://www.shopbottools.com/getting_started.htm

On that page, scroll down to 'How I zero the Z to the bed'.

Good luck,

Nat