Table Limit/Definition Messed Up

[Chuck Keysor]

Hello Again,,,,

How do I restore my table dimension definition/limits?

I was using my Keypad to move my bit around so as to mark a long straight line down the middle of my 16 foot long board. My Bot is 5' x 12', so I was surprised when my spindle got to x = 109 inches, it stopped and gave a message saying I had reached the limits of my table definition.... It offered me the chance to manually over-ride the limits, which I did to finish my operation.

How do I reset my table limits? I don't think I have ever had to do anything with this. I have in the past resurfaced my entire table top without problems, but haven't used the entire length of my table in a long time. I bought my machine used, and so things like this were already set-up. I have done some looking at past threads, but couldn't quite figure out what the correct subject would be. So I am coming back once again asking for help :o.

Thanks again, Chuck

[jzarski1]

I think you do a VR command.

John

[srwtlc]

Chuck,

VL (Values - Limits for Table) is where you want to set them, but you should also make sure that your machine is set to true table home with C3. That is if you have already set up that with the proximity switches and TS (Tools - Shopbot Setup) or manually set it in MyVariables.sbc file.

[Chuck Keysor]

Hello Scott. Thanks for your reply.

I just now got done checking out my table limits. I looked at the VL page, and it was already set up correctly: Low X limit: -.5
Hi X limit: 144.5

I went, gee, that is odd. So I tried a simple MX 140 command, and I got an error message which read: "X axis beyond software table limits."

I did MX 110 and it moved as it should, without any error messages.
I did MX 111 and I got the error message.
I did MX 109 and the gantry moved as it should

I was given the option to over-ride the limit, which I did, and the gantry moved as it should have.

I poked around at various tables, and didn't see anything even marked 111 that would have suggested a value error that was triggering this problem.

Also, I do have proximity switches and my C3 command works fine.

Any other suggestions would be appreciated! Again, thanks, Chuck

[srwtlc]

Hmmm, are you sure that your current working 0,0 location isn't somewhere other than true table base 0,0? Seems like X0 would have to be somewhere around 33.5 inches downstream from the table base 0,0. Once you issue a C3, you should be set to table base 0,0 and be able to move 144.5 before getting the out of bounds message. Are the offset values in your myvariables.sbc file set to the actual distance from table base 0,0 to where your prox switches trigger?

[Chuck Keysor]

Hello Scott. Sorry for my slow reply.... I have gotten caught up in a local election campaign, helping out a couple of friends.... The election is today so this will soon be out of my way...

Anyhow, I did re-zero my table with the proximity switches this morning. I checked all over in Shopbot3 and couldn't find anything called myvariables.sbc (I also searched my entire computer using the search tool).

I rechecked VL, and that was still fine as previously reported. I found a page of "Values and settings" and that said "Base coordinate offset x axis = 0". I looked through everything I could, but didn't find anything that gave me an indication of an offset being present.

I went and ran what I needed to run on this long board, and then had to slide the long board to the left so I could surface the entire board.

What do I do next to find why my table seems to be limited to moving 110" in the X axis on my 144" long bed????

Thanks, Chuck

[srwtlc]

Could your X+ prox switch target bolt have gotten moved closer to X0 somehow? Loosened up and vibrated along the rail slot, snagged and dragged, bumped, etc.

[Chuck Keysor]

Hello Scott. Thanks,,, I just now went and looked, and the rail stop is still stuck on with double sided tape where it has been since I set up the machine. So that isn't the problem.

In the past when I have had the gantry hit the limits set by the proximity switches and the stop bolts, there is a danger flashing red simulated LED on the SB3 control panel and it locks everything up.

This acts very differently. The gantry simply stops, and gives whatever message I cited above, and asks if I want to manually over-ride the limit. When I say yes, it just moves on and works for that cycle.

I'll have to call Shopbot tomorrow, as I will be ready to get back to work with my machine. (Right now my table is tied up, as it is the only really flat big surface in my shop, I did a glue up of some 15 foot long boards, and did that on my Bot bed.)

I'll post what ever is determined to be the solution when that is determined.

Thanks, Chuck