Zero Plate

[toe_jam (Unregistered Guest)]

.122 is the thickness I get for the Z plate. I know there is a file somewhere that has the thickness of the plate for zeroing. But I need to make sure that the measurement I get with a caliper is the same the shopbot is being told. I'm not getting exact depth, it's going a little deeper than it should. Where can I check this?

[gerald_d]

The default value is in the file C:\SBPARTS\ZZERO.SBP. Do not worry if your measured plate thickness is not exactly the same as the value in the file - the important thing is that the ShopBot should not be going "a little deeper than it should". Change the value in that file until the SB goes to the correct depth.

For example, if your zzero.sbp file also has a value of .121" (same as your measured plate thickness) and you are going .01" too deep, then add .01" to the value in the file to give you .131". The only important thing is that it cuts right - the actual numbers are irrelevant.

[mrdovey]

I wrote an SBP program so the ShopBot could measure the thickness of my z plate to avoid measurement transfer error. I know it's around here somewhere - if anyone would like to use it, let me know.

[Brady Watson]

"toe_jam"...

You can edit the thickness of your Z-zero plate in the zzero.sbp file in SBParts. You want to change the value of the line that says:

&ZBot = .131

In your case the line would read: &ZBot = .122

This will not cure your problem of the bit going deeper than it should...In all actuality, changing this value to .122 will make the router higher by .008".

You can check this by changing the value in the zzero.sbp file on top of the spoilboard, then do a MZ, .122. Then slide the zzero plate under the bit. It should be a snug fit. If not, then either your unit values for the Z-axis are off, or your micrometer is off. While you are editing your ZZero.sbp, change the MS to something a bit slower to get a more accurate reading...no electric motor stops instantly.

-Brady