Z Zero Plate Operation - Comments?

[steven_p_sparrow]

Hi All,

I'm a little shy of using the Z Zero plate up to now. I have the SW set at the correct plate thickness (0.125" in my case) but early results (when I was even less experienced than my current inexperienced state!) were less than encouraging. Now I'm up to using shiny and expensive 60 degree V bits, I just don't want to risk breaking the tip off such a piece of gold. Without some easy to use and accurate zeroing system, accurately zeroing Z, especially with the stock dust foot fitted, is a real chore. Also, when using a flat area clearance tool, the need for accuracy on the vee bit zero is magnified, hence the need for a better method.

What to others do? Does the Z really stop instantaneously, as soon as it makes contact? Any comments would be greatfully received.

The only thing I have though of to date is to use a slow Z speed when zeroing to cut down on Z axis inertia and momentum but whilst I'm brave, I'm not that brave!

"There are old Pilots and bold Pilots, but there are few old, bold Pilots'

Regards

Steve

[feinddj]

you might try the super zero plate. It zeros z and can zero x and y at the same time. the program seems to be a bit softer landing than the z zero routine. That said, I have never had any problem snapping a tip off a bit with either. the only thing that I watch out for is to make sure (by touching the bit to the plate) that I have continuity.

[dubliner]

One thing to do is , use the keyboard to lower the bit close to the plate, escape, C2, then the plunge is slower. Although I have never chipped a V bit either, sometimes I drop it down as I'm impatient. Being so close to the plate doesn't allow any ramping up. , Oh by the way, I think we all still break bits ( I do, less frequently albeit )

[myxpykalix]

I have used the Z zero plate with v bits from a large height and have never had a problem with any bit breakage. I believe the normal Z zero plate thickness is .121 not .125

[dlcw]

Also, the z zero plate is aluminum which is a lot softer then the carbide tip of the V-bit. You'll notice indentations in the z plate but no damage to bits.

[michael_schwartz]

I have been using my ZZ plate with sharp V bits without any problems. I forget the thickness of my plate, but I did check it with calipers before I set it. I think I remember the default being correct.

[adrianm]

I amended the standard Z routine to remove the initial "fast" move and do only one slow move. Seems to be gentler that way.

I always touch the plate on the bit before starting the routine to make sure contact is being made as well.

[rb99]

If the bit is indenting the aluminum would the zero not be out that amount?

RIB

[Gary Campbell]

Steven...
Many of us have "tuned" the speeds and move distances in the OEM Zzero file to make them suit our needs. You may want to slow down the speeds of both the initial and second pass. Also, I have made the second pass roll back shorter.

With thousands of these out there in use daily, I am sure if they werent accurate, there would be noise. There is a much greater chance that some other factor would create an inaccuracy than the plate and zzero routine. Most of these are adjustments to the motion parts and should be part of your routine maintenence.

Once the bit is zeroed, you can MZ to the plate thickness and use the plate as a feeler gauge to check how accurate the routine was.

My old plate was .122, my new one is .1245. They do vary so make sure you mic yours in a few places.

[jdervin]

I too have never seen any damage to my V-bits, but am wondering about the smaller, more fragile bits such as a 1/16" or 1/32" ball-nose. I'm also wondering if smaller bit surface area affects the rate of current flow and hence the accuracy of the Z-zero routine. I suppose this might be true of pin-point V-bits as well. Any thoughts on this from the experts?

[beacon14]

One of the first mods I made on my original machine was slowing the Z drop speed way down in the Z-zero file. Also reduced the retract distance as Gary said.

[butch]

I have been using the Z plate for 3 years and have not hurt any bit yet. I doubt if it would as it is pretty soft. One thing I have learned is that the plate does warp and the mic numbers may not be accurate. I always set my plate thickness then check with a piece of paper under a v-bit. I then set the thickness so the paper will not slide under the bit. I do this before any item that is extremely important to be accurate for Z depth.
One thing - don't forget to remove the plate after running a z - zero. I have a few divots in my plate, and don't think that helped the v-bits at all.

[steven_p_sparrow]

Thanks to all for their replies. I feel a little more confident and will try again with bits that matter less first off. Certainly knocking back the Z speed seems to be a good idea.

For sure, it would be pleasure not to spend 10 mins or so on Zeroing when on a two-tool job!

One thing I have found and would like to pass on to other newbies is that one must beware when zero has been set, but Z has to be run back up to re-fit the dust boot. If you hear that clunking (mechanical limit reached) your Zero is lost. This is all too easy to do, another part of my plan is to make the removable dust boot to both save time and prevent this occurring.

Regards

Steve

[Gary Campbell]

Steven....
Once you get used to it, you will zero with the dust foot on