Z Axis Soft Limits Error

[pacebedo]

I've been racking my brains trying to figure this out.

(1) I'm using Vectric Aspire and have generated a toolpath for a toy that I'm making for my sons.
(2) All the toolpaths were profile cuts using both 1/8" endmills and 1/4" endmills.
(3) In the "Drawing" portion of Aspire, I made sure that the job dimensions were correct for the machine that I'm using Basic 8, Z thickness at 1/4" (1/4" MDF), XY Datum position at bottom left corner.
(4) In the "2D Profile Toolpath" portion of Aspire, I made sure to set the cutting depth to 0.28" (so it cuts through the material), Safe Z set to 0.2" with Home position set to X:0.00, Y:0.00, Z:0.50
(5) Then I set files for 2 different bits and labeled them Part 1 for the 1/8" bit, Part 2 for the 1/4" bit

(6)  I turn on the machine and Home All.  Router goes to the datum position X,Y=0
(7)  Then I do the Touch off with the puck.  Router slowly goes down, touches puck, pauses and then goes up again. Registers a number.  I'm assuming that the machine now knows that it is zeroed on all 3 axis.
(8)  I run the file, Part 1.
(9)  I get the error reading "Z Axis Soft Limits".

What am I doing wrong?

I've tried several attempts of correcting the problem myself before resorting to the forum, ie:

  (10)  RTFM x4
  (11)  Manually setting Z Axis using the STEP mode and a piece of paper
  (12)  Bringing the endmill a little further down the collet
  (13)  Recalculating each toolpath in Vectric and replacing the files.
Any help or advice is greatly appreciated.  Thank you. 

[pacebedo]

One more thing I almost forgot...

(14) After I have the endmill touch the puck, the router raises, I have set Z to 0. As a result of doing this, the file would run but it cuts air instead of wood. (I'm not sure if that helps out a bit as a clue).
(15) When I don't set Z to 0, I get that error state "Z- out of soft limits" error.

Please advise. Thanks.

[stevem]

In your description, you say you have your Z0 set to .5
If you are setting the Z0 to the top of your material, then don't set your Z0 to .5.
When I am cutting almost anything, I always set my Z to the top of my material. Then when I use the Z puck, everything should cut correctly.

Just make sure when you start a project, you set your dimensions properly as to size and thickness.
Example: X=12", Y=10" and Z=.25". Then set your zero position to top of piece. Use the puck when you zero your bit and all should work well.
Your safe Z height is fine at .2

The only other thing is if you want to cut thru the work piece of .25, I usually only make my cut depth to .26 or possibly .27.

[gerry]

You set your Z position, but not your XY position. You don't want to cut from HOME X=0, Y=0 (HOME Button). If you told Vectric that your XY Datum position is the bottom left (0,0), then move your spindle to a comfortable XY on the bed, then use your #4 button on the controller (XY >0) to tell the machine to use this as your work XY Zero. You will see that your controller displays X=0, Y=0, Z=0. Your work XY=0 could actually be X=3 inches, Y=4 inches on the bed.

[pacebedo]

I think I'm confused...

In the material setup portion of Aspire, I set my Z1 Clearance height at 0.2" above the material. My Plunge depth Z2 was set at 0.2";

In the Home/Start Position, I set X to 0.0; Y to 0.0 and Z Gap above the material to 0.0. However, when it recalculates, it re-adjusts it to 0.21".

With respect to Gerry's comment, all the pieces I'm cutting are position a few inches off the home position.

I tried setting the home positions but still get the Z- soft limits error.

[traindriver]

So the problem is that for where you set the Z->0 position, when the machine reads the g-code, it sees a distance in your file that is below where it can reach.  Is step 14) that you mentioned in your troubleshooting repeatable?  If so, do that again, and when you stop it, take a look at what the Z position is.  I'm betting that even though it's above your work, it's a small negative number (as it would be if everything worked correctly and it were making the first cut into your material.)  It would be interesting to know how far it is from where it stops "in air" down to the surface of your material, since at the surface, you should actually be at zero.  

[pacebedo]

Yes, the error in Step 14 is repeatable.

Here are the pendant readings I got just after having the endmill touch the puck for your reference:

1X 0.000 MAUN
1Y 0.000 SOFF
1z +85.000 lSP

I then set Z to 0 and run the file.

The router cuts air and makes the cuts. I stop it while it starts to make its first plunge. I get a small negative number as a Z value like -5.000 or something like that even though its cutting air.

[gerry]

Jun 30, 2018 18:07:21 GMT -5 pacebedo said:

I think I'm confused...

In the material setup portion of Aspire, I set my Z1 Clearance height at 0.2" above the material. My Plunge depth Z2 was set at 0.2";

In the Home/Start Position, I set X to 0.0; Y to 0.0 and Z Gap above the material to 0.0. However, when it recalculates, it re-adjusts it to 0.21".

With respect to Gerry's comment, all the pieces I'm cutting are position a few inches off the home position.

I tried setting the home positions but still get the Z- soft limits error.

Are you setting a home position in the controller? Just like you set the Z height for your bit, you must set the starting position on your bed.


XYZ Home

[pacebedo]

Yes, I set the zeros on the home controller (A11). Getting the same z- soft limits error.

I had recently uploaded a software update for the controller after I had a problem with the initializing sequence (see previous post). Chad sent me the file and I was able to continue. I'm beginning to think that the settings have changed. I'm using a Basic 8. Maybe the home settings are different.

[Deleted]

Jun 30, 2018 18:07:21 GMT -5 pacebedo said:

I think I'm confused...

In the material setup portion of Aspire, I set my Z1 Clearance height at 0.2" above the material. My Plunge depth Z2 was set at 0.2";

In the Home/Start Position, I set X to 0.0; Y to 0.0 and Z Gap above the material to 0.0. However, when it recalculates, it re-adjusts it to 0.21".

With respect to Gerry's comment, all the pieces I'm cutting are position a few inches off the home position.

I tried setting the home positions but still get the Z- soft limits error.

The Z1 Clearance height is where the machine will have the bit for doing rapids in X or Y. The Home / Start Position is where the machine will go to when it's done with the toolpath and where it wants to start from. The Z Zero is typically the top of your workpiece but sometimes it makes more sense for you to use the bottom. The machine will rapid from Z1 to Z2 and then use the plunge rate of the bit when going lower. All that being said, I like to set my Z2 at 0.2" and my Z1 and Start Z at 0.5" or even 1" if I have room and clamps are in the way. I wouldn't set the Start Z at 0 as too many things can go wrong and you break a bit or chew through a clamp. Generally, it's a good idea to put Z1 and Start Z higher than Z2. There are cases where I cheat a bit on everything and make them smaller if I'm out of Z movement because of a thick workpiece, a long bit, clamps, or a combination of them.

[pacebedo]

Is it possible that there's something wrong with the limit switch or that the CNC is not formatted properly? Everything was working fine the last couple of times I was using it until I uploaded a restore file from Chad last Friday when I had an issue with the A11 controller. Maybe the settings are wrong.

I've triple checked the settings on Aspire regarding the material surface to rule out user error. I've even switched out the thickness of the boards that I'm using (1/4" to 1/2") and still, I get the same problem.

I've checked the table settings on the CNC and, sure enough, the Z is set at 150mm which meant that the cutting depth is 6".

It seems that the machine thinks that the surface of the board is mid-air and starts cutting despite the fact that that it has been zeroed out using both the puck and the manual methods.

[pacebedo]

UPDATE:

At the suggestion of Chad today, he told me that reason I got the Z- soft limits error was because of the bit bottoming out due to the limitations on how far the router bit could go before it triggered the limit switch. As a result, the solution was to add an additional spoil board under what I'm cutting in order to increase the Z height. This has the effect of cutting deeper without triggering the limit switch. He told me to either do that or purchase a longer bit.

It now works like a charm. Now onto my Maslow CNC which does not.

I guess that that's one of the inherent limitations of a Basic 8.

Thank you for all your help. Lesson learned.