Z axis does not completely in 2d but ok in 3d

[neoteric]

I just purchased a used Shopbot. Been messing with it for an entire day. I can run a file created in Millworks perfectly.

However, any file I create with Partworks, (or trial file in Cut2d) the z axis does not return fully, so each subsequent cut drops the router lower each time. I have read through the troubleshooting posted here, and tried various tips, but have had no luck. I have checked by units, that I am properly grounded ( I think) etc. Anyone willing to try to help?

I am a new user, so please have some patience.

I dont even know what information to provide to help you help me!

[beacon14]

Can you post the first few lines and the last few lines of a .sbp file that was created in PartWorks?

All the lines before and after the actual cutting moves (M3s and J3s).

[ken_rychlik]

If you have an up spiral bit it is very possible that the bit is slipping in the collet. It may be using more agressive feed speeds on the partworks file than millworks. I'm not to familiar with that. Measure how far the bit is sticking out of the collet before you run a file and check it when it's finished. I remember about the second or third day I was running mine I had the bit slippage thing going on.

Kenneth

[neoteric]

Here is the files.

Bit not slipping. Actual router does not pull all the way up when going to z. In this case, looks like it is supposed to go up to my safe zone of 3", but it isnt.

Thank you so much for the help. I thought 3d would be the hard part, thats working fine.

Also, shopbot sample files are working fine.

Thanks!
first file

3738 (0.4 k)
second

3739 (1.0 k)

[ken_rychlik]

Perry, I don't know if it would work on yours but my z motor was weak and loosing steps. (I think) I switched the z motor with one of the x motors and the trouble went away.

It kind of sounds like it thinks it went up a certain ammount, but really it didn't. Then it dives further each time.

Kenneth

[neoteric]

Kenneth I dont think it is a slipping problem, as it seems to work perfectly under the following conditions: Moving with keyboard.
Sample files from Shopbot. Millworks.

Does not work with Partworks, which is what I really need. Incidentally, I reinstalled completely. No avail. Here is another file that does not work. Z axis does not come all the way up.

Thanks for the suggestion Kenneth!

It seems to work fine on millworks, does not work on partworks files.

Attached is another file that does not work.
Fresh install

3740 (19.2 k)

[neoteric]

ok. so maybe it doesnt work in Millworks.

works fine in Millworks for one sweep.
But on second sweep, does not return to corner of material (0,0,1.5) only makes it back 1.4 of that. It seems my "returns" arent working.

I have tried putting the speeds way down, still no luck. ANYONE have any ideas?

[ken_rychlik]

when it comes back to the 1.4 is that what the readout says for the current position?

Also if you finish running a file then do a MZ,1 will it actually be one inch above the material?

I am trying to get you to figure out if it is the machine or the file. No matter what the file tells it to do, if the machine read out is correct on the placement of the bit, then the machine is ok.

Kenneth

[neoteric]

Been testing further. Here is what happens, pretty much without fail.
First pass, whether in 2d or 3d, cuts correctly.
So, if its a bunch of circles the first circle would be correct. Then the z raises up. The readout thinks it has gone all the way to the safe position for z, but it has not. Then the z would lower to what it thinks is the next position, but it would actually be lower. If I cut enough circles in the air, it actually gets to the point where the z gets to the table.


However, if I use the K command, I can go all day, up down left right, it never loses its place. Always in perfect measurement.

So what is the difference between using the keyboard to move the router and what the file is doing to move the router? Are they stepping differently?
Sorry, I am so new at this, but something is not correct. The table was bought used last week, and the person demonstrated a simpley 2d cut when I picked it up. It is from 1999. I have double checked the Units. It does have a new controller.

Thnks for trying to help.

[ken_rychlik]

That's wierd. The only thing that comes to mind is that the move speeds with the keyboard and the file are differnt. The keyboard will use the move speeds you have entered on the left side of the screen at the pc the bot is hooked up to. The file will state the move speeds for the file when it starts.

Edit the MS which is the move speed on the file and try to air cut it again. Mine is a 2004 prt and jog sppeds of 7-10 inches are ok without it loosing position. Move speeds or (cut speeds) I usually run more in the 1-3 inch per second. Z speeds are usually one inch or less per second.

Either way if the readout on your screen is supposed to have the tool one inch above the material and it is not, then the machine is at fault. It may be that the machine is being asked to move faster than is comfortable for it and the file is making it happen by asking it to exceed it's comfort limits.

The one file I looked at that had the 6 for the move spped seemed pretty fast to me.

[ken_rychlik]

Another thought after looking at your files again is there are lots of J3 which is jog speeds. That uses what you have enetered for a jog speed at the pc. You may try slowing them down. jogging is fine going to a place to start cutting, but during the cutting process it should be the MS or move speed that is used.

Either way if you change the on screen Jog sppeds to say 2 ips for the x and y and 1 ips for the z, then the files with the jog info will only run as fast as your inputs for jog speeds.

[neoteric]

will try that now.

[neoteric]

no difference.

[ken_rychlik]

Perry,

Either way you look at it, if the controls tell you one thing and the tape measure tells you something else, the machine has lost it's place.

[neoteric]

OK, Your last statement led me to some more testing!!!
At same speed set for Jog and Move, moving takes me the right distance, jogging about 1/4th the right distance! This is true in absolute and relative mode. So .... what do I do to fix?

[neoteric]

Its clearly my jogging. I learned to replace the J's with M's in my SBP. Works.

So how do I tell the software that my J = my M?

[ken_rychlik]

That is really strange for the jogs and moves to take different measurments.

I run vcarve pro and it does jog for getting to the cut, but then moves the rest of the way.

There are unit values for x,y and z, but they should work the same for jog and move.

So you really have two seperate issues.

Try reloading the software for both the design program and the sb3.

I think the software company would be the place to ask the question on when it jogs and when it moves.

Shopbot should be able to help with the jog and move issue not going the same distance.

After reloading everything, ask each question in the correct place if the trouble is still there. I understand what it's doing for you now, but I don't have an answer for you.

Kenneth

[ron brown]

My ShopBot is 'evolved' from an early cable drive unit. I recently upgraded to a V4 Board.

I don't know much about the newer systems. If there was a weak or non-existent Z-lift spring it would give similar symptoms. A dirty 'rack' or ball-screw needing cleaning would also cause the Z axis motor to loose steps.

Ron

[ken_rychlik]

Ron, the part that has the move and jog commands taking the machine different distances is what is puzzling me. That's why I was thinking he needed to re-install the sb3 software.

Perry, It is a free download in the support section of shopbots home page. Just figure out which one suits your machine best.

Kenneth

[neoteric]

I reinstalled all software on a different PC.
Same issue.
It isn't the design software. In the shopbot software, manually entering, if I type jx 15 it does not go 15. If I type mx 15, it goes 15. So it must be a setting or something.
PS, this is a very old machine, but with new controller. I think it is not the machine, since it moves correctly, but jogs incorrectly. I think it is software setting?

[ken_rychlik]

Did you install the software from a disk you got with the machine, or from the shopbot website?

[neoteric]

From shopbot website. Was only different by one release.

[ken_rychlik]

Call shopbot in the morning and they should be able to tell you why it's happening. They treat customers that buy used ones very well. Tech support is free but parts are not. lol

The other thing on when the software tells it to move or jog won't matter that much if you get this taken care of.

[ron brown]

I still think jog speeds too high and/or dirty track, improper springs, too tight hold-down or something like that.

In older machines motor stall was a problem.

Ron

[Ryan Patterson]

Perry,
What version software are you using? Do you have a V4G board? It sounds like you are using settings for an alpha. Go to values then units [VU]. Then look for Resolution Multiples for alpha Step Drives. Are any of these greater than 1? If they are you have the wrong settings file. To correct this, go to Utilities then Reset [UR] and follow the prompts.

If the above is not the case then try to narrow the problem down. Try to duplicate the issue from entering command like MX and JZ. Try at a few speeds Jog speeds and move speeds.

[neoteric]

Problem Solved. Finally got back to it. RLI.

It was in fact the resolution settings under the unit values, which should be set to 1. Bad info from the seller. THANKS TO ALL FOR HELPING!!