Z Zero won't reset for some reason

[bill_moore]

That is the message I get now when I try to use the z zero plate. The light comes on z axis stops but it stays there. I have done this 15 or 20 times a day for 3 days and all of the sudden this happens. I have been changing the setup thickness to meet my needs and went back to be sure the decimal was there and all is correct. Has this happened to anyone else and if so how did you fix it? I found nothing on this in the archives.
Thanks

[gene]

Bill,
I would call Shopbot and see what they say . Is this a new bit ? With what you are saying it seems that it may be in the software

[drodda]

I had this happen if the bot had to travel too far to touch the plate. It would not zero. So I moved the bot lower to the material then ran it again and it worked fine. There is a limit it will travel to touch the plate. The file sets this limit, perhaps you are above this limit when trying to zero?

[bill_moore]

Thanks guys I'll call this morning. Same bit all week and bit was normal 1" up and on the numerious attempts since I have tried several heights. If SB gets it streightened out I'll post so the arcive will have it.
Bill

[dana_swift]

Bill.. I had a wire fray in the harness that allowed the zzero detect line to touch the frame. So I was getting false zzero detects. I figured out what the problem was just watching the light on the SB3 program and noticing it came on at the wrong time. That got me wiggling things until I figured out where the problem was.

I ended up moving the section of wiring so it couldnt rub on things and applied electricians tape to the exposed wire.

Problem solved. ZZero works like a champ again.

D

[dray]

tap the plate on the bit and see if the red light comes on on your screen. If not you have a broken wire or bad connection.

[bill_moore]

Thanks for everyones comments. I got to the shop this morning and the problems had multiplied. Lost the usb communication and some other things. I decided I better reinstall the SB3 software( should have done that first looking back LOL ) That took care of the problem but brought back an old problem I had a few months back. Now almost every time I cut a file it stops like it hit a limit switch somewhere in the cut ( never the same place ) guess this will work out somehow. I downloaded the most recent version I am thinking I will go back to the last one and see if that helps.
Thanks again
Bill

[Gary Campbell]

Bill...
I keep a download of the last few versions on my control computer. Different versions react with the machine differently, especially when it comes to prox sensitivity and the ever plagueing erroneous stop hits. I have the best luck with ver 12, but 15 has been working well for a couple weeks.

Funny thing tho... some versions show up with as much as .050 difference in the positions of the XY zero routine. Input switch timing? Software fix for potential hardware snafu? Dont know yet.

Make sure that you install the firmware with each version change. Its best not to mix and match.
Gary

[beacon14]

it stops like it hit a limit switch somewhere

I have found the prox switches not to be extremely reliable. If one of your prox switches is going bad it can trigger spontaneously and create the kind of error you mention. They can false trigger if the little screw is too tight (and they can pivot if the screw isn't tight enough).

[jastod]

We also had a problem with the Z Zero routine with Version 3.5.15. The bit would come down and touch the plate once, but then when it went to touch the plate a second time, it would stop part way down. Then an error would pop up saying that the Zero couldn't be found. Here was the fix. If the Z Zero height is set at over 2" in Shopbot set up, the Z Zero routine wouldn't work. If the Z Zero height is set at 2" or less, it works fine. We changed the Z Zero height in Shopbot setup and haven't had any problems since. This appears to be a result of a change in the Z Zero routine in the latest software release.