Z zero plate

Post by **Burchtree** » Sat Feb 24, 2007 11:38 pm

Hi all
I made a new Z zero plate for my shopbot and I would like to share it with you. My Z zero plate was made out of aluminum but I was still worried about very pointed V bits hitting it and breaking the point. I needed a Z zero plate that could flex.
I machined a step .125 deep 6 inches long in a piece of brass .375 thick 2 inches wide by 8 inches long. Drilled and tapped 4 holes I next drilled the 4 holes in the Z zero plate.
I have run the Z zero routine 10 times and repeats good I was amazed at how much the aluminum plate bends on the first hit of the Z zero routine.( That could break a point ) The second hit does not seem to move the plate.
Dan

Post by **Perry** » Sun Feb 25, 2007 4:01 pm

GREAT Idea Burchtree!!!
I hope you don't mnd, but I think I will adapt that for my use also
Thanks for sharing.

Post by **Burchtree** » Sun Feb 25, 2007 4:38 pm

Thanks Perry
I was hoping people would find the idea useful and feel free to improve on it
Dan

Post by **Phil** » Sun Feb 25, 2007 4:45 pm

Thanks for posting Burch. I'd given up on using the zero plate for V-bits. I broke too many points.

Post by **RoutnAbout** » Sun Feb 25, 2007 4:45 pm

Dan,

I'd have to agree with Perry, Thats a great fix to small problem, I've been attempting to come up with one that was a short box with a spring top. I guess I was over designing it. Thanks for the Post. I'll have to duplicate this. Might even Vcarve the name Dan's Zero plate.

Great Idea.
Thanks Dan

Post by **brockadeau** » Mon Feb 26, 2007 12:05 am

Looks like a great solution-- On a non shopbot machine, does anyone have an easy wiring solution for the zero plate? Treat it as the bottom limit switch for the z axis? Is there continuity through the router to complete the circuit?-- anyone have any help?-- thanks-- Jack

Post by **dman** » Mon Feb 26, 2007 2:51 am

Hi Jack,
I don't know what controller software you are running but in Mach 3 I just completed making a z zero plate and have it wired as a probe. I really like the design Dan has come up with and will look into making one like it for myself. Right now I just have a solid plate. I have it set up to lower the z at 5ipm so hopefully a vbit doesn't get damaged. Works great so far. For the info on making the plate, I found cnc zone and the mach forum on yahoo helpful.

Damian

Post by **GripUs** » Thu Mar 01, 2007 11:59 pm

Let me start by saying that 4 years ago I couldn't even spell CNC and everything I know I have learned the hard way. I may be presenting a solution to a problem that doesn't exist or you may have a much easier way to accomplish this. I manufacture pistol grips so most of my cutting is repetitive and I always zero my "Z" at the spoil board. I move the bit over the black dot just south of the aluminum piece (at the bottom of photo 1) and use the Mark I eyeball to center it. Since this is the the "X" and "Y" start reference point those positions are not that critical. I then do a "Zero All." I milled a slot out of the spoil board the same depth as the aluminum strip with the hole in it. I then attach one lead of my ohm meter to the strip and the other to the bit. I lower the bit close to the strip, then set the jog to .001" for the final few clicks (photo 2). As soon as I have continuity (photo 3) I know my bit is touching the aluminum strip. Since it is aluminum and I am moving the bit downward .001" at a time I have never damaged a bit upon contact.

Just thought I would throw that out...maybe someone can use it.

Can't seem to get the photos to show up. Oh well...

Post by **Peter Stenabaugh** » Mon Mar 19, 2007 9:28 pm

Hey guys, here is another and perhaps simpler method of setting your Z zero. What I use is a 1/2" diameter round bar of stainless steel, although most any metal would work. I bring the tool down to approximately 1/2" above the workpiece and then use a fine jog setting of .001" and gradually lower the tool to the round bar. As I do this, I roll the round bar back and forth below the tool, until I feel the tool touch the bar. All I need to do then is reset Mach 3 Z setting to 0.5000" and we are done. It only takes a couple minutes to do this, and it is very accurate, likely getting you within less than .001" each time, but more than accurate enough for woodworking. With this method there is little to no chance of damaging your cutter as you are only using light finger pressure to roll the bar below the cutter.

I use the same process on my milling machine, except it is even easier as I can carefully raise the table to achieve the same effect, which is even a bit faster for me. The only difference here is that my round bar is a hardened steel bar, but being careful there is still no chance of tool damage.

Using this method tool changes only take a few minutes and you can have really accurate repeatability if you need to re-set the same tool again on the same job.

Pete

Post by **dighsx** » Tue Mar 20, 2007 2:37 pm

Hey Dan when are you going to start selling them? Put me on the list

Post by **RoutnAbout** » Tue Mar 20, 2007 8:09 pm

dighsx wrote:Hey Dan when are you going to start selling them? Put me on the list

Yea, put me on the list also. In fact if your coming to the conference we could exchange cash or talk turkey there!!

)

Post by **ddlawrence** » Wed Mar 21, 2007 6:21 pm

Nice work. Can you tell me the sensor manufacture & part number?
Do you use the same wiring and z-zero program?

I will pay for the plans if you have them.

regards........don

Post by **Burchtree** » Wed Mar 21, 2007 9:33 pm

Hi Don
I don’t have any plans on how to wire up a Z zero plate on a machine. My ShopBot was set up at the factory with that option. What I did was improve on the factory Z zero plate.
Jay and Don are you are serious about buying a plate ? If so that makes three. I did check into the price of brass for the bottom piece. $46.00 per foot! Well I think brass is out. I could use corian and a brass top plate Black corian or blue for a ShopBot and or make the whole thing out of aluminum plate.
Dan
P.S. Maybe CNC Jay’s would even stock it in his store

Post by **dighsx** » Wed Mar 21, 2007 10:03 pm

CNCJay would be happy to be your retailer for your z-plates. I'll wing ya an email.

P.S. I just bought a place in Lewiston (about 18 miles east of Gaylord). So we'll be closer neighbors now. hehe

Post by **DavidCousins** » Tue Apr 10, 2007 8:12 pm

Hi,
Can someone point me to the zero routine? Is it a Mach3 routine?

Also, is this device have just one wire? Or are there two wires, that connect when the top plate bends and touches the bottom plate?