Nesting Part Files in 3D using [FP] and [VA]

[BrandanS]

Good Morning SBotters, it's almost the weekend ,

So here's a situation I could use some input/help with:

I am running 8 parts in a fixture, these parts are 48" long. I will be performing a profile operation on each end (LeftSide and RightSide) to clean the part and add some features. I have written a masterfile to run my profile operations as routines with [FP] which are offset with parameters after a move to the said offset. Both routines have zeroes off the ends of the parts and z on the top of the part.

Something like this (with 3 parts to simplify):

M2, 0, 0
LSprofile.sbp, , , , ,2 'Run LS profile on Part 1
M2, 2.000, 0
LSprofile.sbp, , , , ,2 'Run LS profile on Part 2 (which is offset 2.000" behind Part 1)
M2, 4.000, 0
LSprofile.sbp, , , , ,2 'Run LS profile on Part 3 (which is offset 2.000" behind Part 2)
'
'Insert Jog moves to Move around the fixture)
'
M2, 4.000, 48.000, , , , ,2
RSprofile.sbp, , , , ,2 'Run RS profile on Part 3 (48" from the left side)
M2, 2.000, 48.000, , , , ,2
RSprofile.sbp, , , , ,2 'Run RS profile on Part 3 (48" from the left side)
M2, 0.000, 48.000, , , , ,2
RSprofile.sbp, , , , ,2 'Run RS profile on Part 3 (48" from the left side)
'
'Insert Jog Commands to come Home near the Beginning of Part one.

Looks very similar to what you find in the first few pages of our User Guide right? Simple enough. This is nice as it doesn't care about where my Z is, and I can hold at a Clearance Distance 1.000" above my part as I come in and out of my routines.

Now, my part is actually .020" higher on the right-end (RS) compared to the left-end (LS)(poor fixture design/maintenance, table issue; or whatever doesn't matter). So I want to also offset my Z to compensate. At first glance it may look something like:

M2, 0, 0
LSprofile.sbp, , , , ,2 'Run LS profile on Part 1
M2, 2.000, 0
LSprofile.sbp, , , , ,2 'Run LS profile on Part 2 (which is offset 2.000" behind Part 1)
M2, 4.000, 0
LSprofile.sbp, , , , ,2 'Run LS profile on Part 3 (which is offset 2.000" behind Part 2)
'
'Insert Jog moves to Move around the fixture)
'
M2, 4.000, 48.000
MZ, 0.020 'Move to compensate for Z difference and Run Routine in 3D [FP]
RSprofile.sbp, , , , ,3 'Run RS profile on Part 3 (48" from the left side) in 3D [FP]
M2, 2.000, 48.000
MZ, 0.020
RSprofile.sbp, , , , ,3 'Run RS profile on Part 3 (48" from the left side)
M2, 0.000, 48.000
MZ, 0.020
RSprofile.sbp, , , , ,3 'Run RS profile on Part 3 (48" from the left side)

Great! This would be fine except that I move my tool to the Zero of my part including the Z. Which means gouging or touching the top of my part before I run my routine. The RScode would produce:

Tool at clearance
Move to X/Y
Move to Z (face of part and GOUGE)
Move to 1.000" clearance above my part (from routine)**Facepalm**
Run Routine *sigh*

So, seemingly, this is not the way to do this. I need to be able to set my Z to a location without a move command.

This looks like it can be accomplished with [VA] and it's parameters. Does anyone have a simpler solution?

Thanks again in advance,

Brandan

[srwtlc]

Keep in mind, that running a file in 3d offset considers the current location as 0,0,0 and the file will run from that point. Not a good way of handling this. The best thing to do would be to correct the underlying problem of your setup, but what you can do here is use the VO (Value Offset) command (See the ComRef.pdf).

Here's how it would be set up in your master file....

J2, 4.000, 48.000 'Assuming you're already at your clearance height of 1"
VO,1,,,0.020 'Turns on offsetting and set the Z offset value either +/-
FP,RSprofile.sbp, , , , ,2 'Run your file as normal in 2d offset
VO,0 'Turns off offsetting
J2, 2.000, 48.000
'Wash rinse repeat....

Instead of turning off the offsetting in your master file, I'd maybe turn it off at the very end of your XXprofile.sbp file. If you find that the offset is a bit different from location to location, you could use a variable for the offset value.

[BrandanS]

Perfect Scott,

I think the [VO] is exactly what I needed; I can't believe I missed that! I really like the idea of turning off the offset at the end of the called files !

Thanks so much again Scott,

Brandan

[BrandanS]

Hey Scott,

Something I was think about when using the [VO] command. I should be able to use it for the 2d offsetting as well? Something like:

J2, 4.000, 48.000 'Assuming you're already at your clearance height of 1"
VO,1,,,0.020 'Turns on offsetting and set the Z offset value either +/-
FP,RSprofile.sbp, , , , ,2 'Run your file as normal in 2d offset
VO,0 'Turns off offsetting
J2, 2.000, 48.000
'Wash rinse repeat....

Adds an additional motion where the SB moves to X4.000,Y48.000, sets that to Zero, and then executes the file which may use a different starting location.

Turns into:

VO,1,4.000,48.000,0.020, 'Turns on offsetting is 3D, (X,Y,Z)
FP RSprofile.sbp 'No need for offset variables in [FP] call syntax
'RSprofile.sbp terminates with VO,0
VO,1,2.000,48.000,0.020
FP RSprofile.sbp
'Wash, rinse and repeat

So long as the [FP] called prior to the next [VO] leads out to a safe location, the first motion will now be the first motion line of the [FP] but offset via [VO]. This will eliminate the extra motion between FP files. The other advantage is that now there is only one location to change offsetting (for those who need to 'fine-tune' ) and eliminates some code.

Does that make sense?

Thanks,

Brandan

[srwtlc]

Oh, now your just making my head hurt at the end of the day!

Wouldn't the offset have to be the distance from the end (JZ up) of the previous file to the beginning of the next? On second thought, it would be the distance from 0,0 to the first cut move. ? You'd want to remove the J2,0,0 from the beginning of the file or it would still move that extra amount.

This is one of those that I'd have to try so my dyslexic mind didn't mess me up. I'm sure it would work as desired, just needs to be set right. Give it a try with a couple of simple files and see if it positions as desired.

[BrandanS]

Scott you're right,

This is not really what I am looking for. I want to keep what we have but remove that extra motion. I have attached an image to clarify.

Thanks,

Brandan

[srwtlc]

Brandan,

I'm struggling with how to explain this, but here it goes.

The offset XY values should be the offset from the start of the first part to the start of the second part or between any common points, which would also be the offset from datum to datum. This is easiest if the toolpath is the same for each location, which I'm assuming yours is, for all the left side and then the right side. So, you should be able to use your same offsets, just apply them from start point to start point instead of datum to datum. Your first cut would be run normally and the following ones would be offset. Your file for the cut should be edited to take out the J2,0.0,0.0 at the beginning and end along with any other unneeded code. Strip it down to just what is needed and put a VO,0 at the end. Your master file would then have the feeds, spindle control, offsets and FP commands and looping if needed.

I hope this is clearer than mud and maybe the attached files will help. Place them in your C:\SbParts folder and run the master file in preview. The called file is just a 2" circle that is 1.5" from 0,0 to it's center. The PAUSE UNTIL in the master file is commented out for preview mode purposes.

If it doesn't work for your part, then come back and we'll hash it over some more.