[BurrMan]

Advising people to keep current video drivers is very bad advice. I had to skip several versions before updating because there was an issue with the drivers that would have overheated my video cards. Updated video drivers means ones that are compatible with your system (just like your system BIOS), which I have. I have the latest version of BobCAD as well. The issue is in the software, not the system. Besides, the Verify is very lacking in features as well.

Actually, most of the top software companies will provide a fully functional demo version. At least for me, now I will not purchase software unless I can use a fully functional version. When BobCAD calls to update to the next version, it won't happen without a full demo to use. I don't mind limited capabilities, but you should be able to at least use each feature of the software. They can put a 30-60 day time limit on the software easily and allow full functionality.

BobCads Demo softwares will post code for like the first week, then stop. (I dont remember the exact amount of time.) They are also supposed to be "fully functional and have no limitations" other than the fact that they dont post gcode. (I think the 3d toolpaths quit computing after that initial time slot too. FYI

As far as advice to update your drivers....This is "Common Practice" with developers when the issue is video related on a product that works. The built in predator verify is a very limited view of the feature cut and wont get any better with a driver update LOL. But it sounded as if you were having problems running the verify, and this would be a legitimate suggestion. The other thing to clear up with the verify is that if you are running the demo, it will only verify up to the posted code!!! So if you are being limited to "30 lines of gcode" with a demo version, the verify will halt 30 lines into the verify.... Again FYI

[stevespo]

At some point last year I wrote a custom post (for Mach) that provides a simple form of tabbing. There were some issues with dealing with arcs, but it will break straight line movements, and create tabs of a desired length and height.

It's kind of a PITA to deal with installing the custom posts, but it's been documented fairly well on the BobCAD support site. If somebody wants to play with the code, I'm happy to pass it along. It's a bit limited, but I use it all the time and find it helpful.

I can package it up and upload it later tonight or tomorrow and perhaps someone else can give it a try and let me know what they think.

Steve

[BurrMan]

Tabbing has certainly come up before and I think I remember that Steves solution was liked and used by a bunch of the guy's involved in the last "how to tab" thread.

You may want to check this out....FYI.

Thanks for chiming in Steve. I couldnt find the thread where you last discussed this.

[Magnum164]

BobCads Demo softwares will post code for like the first week, then stop. (I dont remember the exact amount of time.) They are also supposed to be "fully functional and have no limitations" other than the fact that they dont post gcode. (I think the 3d toolpaths quit computing after that initial time slot too. FYI

As far as advice to update your drivers....This is "Common Practice" with developers when the issue is video related on a product that works. The built in predator verify is a very limited view of the feature cut and wont get any better with a driver update LOL. But it sounded as if you were having problems running the verify, and this would be a legitimate suggestion. The other thing to clear up with the verify is that if you are running the demo, it will only verify up to the posted code!!! So if you are being limited to "30 lines of gcode" with a demo version, the verify will halt 30 lines into the verify.... Again FYI

I am running the full version not a demo. Don't want to go OT but did want to clarify that.

[Claude Boudreau]

Hey Claude,
The file I posted just does the tabing down at some depth... So it is not "toolpathing" the tab at the entire stocks depth. But, you would have to run a pre-profile that took the stock down. There is no option that will say "profile down to this depth, then do a tabbing finish cut". This would just need to be setup with 2 profile features.

Did you look at the file I posted? It will verify the tabbing. This tabbing is happening at -.4 deep. The depth of this tabbing cut is .01... I think this is what you were refering too. Is something missing here? I just didnt add the "Pre-Profile" op that would show taking the stock down to that depth first.

Hi BurrMan,
I see, should be easy enough to do, profile to the top of the tabs with multiple pass , then do the tab profile.
Just a few things , your example seem to show your rapid at Z=0 even though you have the clearance set at .1 in milling stock edit...

One last thing , I guess the contour option does not have a 3d feature capable of following a tab drawn as an arc or the top part of a triangle per example. You would have to use 3d engrave to cut those? this would eliminate the rapid move by creating a continous contour for the tab profile.

[BurrMan]

Hi BurrMan,
I see, should be easy enough to do, profile to the top of the tabs with multiple pass , then do the tab profile.
Just a few things , your example seem to show your rapid at Z=0 even though you have the clearance set at .1 in milling stock edit...

Yeah I saw that. There is also a rapid height in the feature edits and I was previously saying that setting this would move those rapids down to that tab level, but one quick play didnt do it and I didnt go any further. You just pointed out that the stock edit also has this rapid value, so i may go back and try setting the value in "Both" to see if it does it. This would be a flaw in this method if I cant drop that rapid move down also....

One last thing , I guess the contour option does not have a 3d feature capable of following a tab drawn as an arc or the top part of a triangle per example. You would have to use 3d engrave to cut those? this would eliminate the rapid move by creating a continous contour for the tab profile.

Yeah. I think thats the first example you were refering to also...AND, if the part has 3d geometry to begin with, then it's just a simple matter of extracting that edge setup and doing the 3d engrave..Seems for sure a better way to go. Even as you stated, it could have been easy enough to just translate those little break segments up in Z the tab thickness and use line join to get the same result from the 2d geometry example I made...


Anyway, I'll try to look at it tommorow also to see if I can manipulate that rapid move. I coulda swore I had done that before

[Claude Boudreau]

Yeah I saw that. There is also a rapid height in the feature edits and I was previously saying that setting this would move those rapids down to that tab level, but one quick play didnt do it and I didnt go any further. You just pointed out that the stock edit also has this rapid value, so i may go back and try setting the value in "Both" to see if it does it. This would be a flaw in this method if I cant drop that rapid move down also....



Yeah. I think thats the first example you were refering to also...AND, if the part has 3d geometry to begin with, then it's just a simple matter of extracting that edge setup and doing the 3d engrave..Seems for sure a better way to go. Even as you stated, it could have been easy enough to just translate those little break segments up in Z the tab thickness and use line join to get the same result from the 2d geometry example I made...


Anyway, I'll try to look at it tommorow also to see if I can manipulate that rapid move. I coulda swore I had done that before

Try it with 2d profile , doesnt recognize the tab,and cut as a straight contour.
I was hoping there was a way to do multiple pass cutting a 3d contour .If only the engrave had multiple pass option it would be easy.Since 3d engrave doesnt have multiple pass either, unless someone found an other way, 2 operations seem the way to go.

[stevespo]

Here are some things to play around with.

If you're using an unmodified Mach3-Router.MillPst then the easiest thing is to just drop these two files (look in the .zip archive for ArcFix-Mach3-Router.MillPst and ArcFix-Mach3-Router.CustomContour) into your C:\Program Files\BobCAD-CAM\BobCAD-CAM V23\Posts\Mill folder, and then select them as your active Milling Stock Post in the CAM Tree Manager.

When you are using a 2d Profiling toolpath, it provides a new Adv Posting dialog that allows you to turn on/off tabbing for that given profile. There aren't a lot of options, and they aren't very sophisticated. You can choose to put a single tab on a line that fits a given range for length (ie. > 1 and < 2 units), or you can choose to put multiple tabs on a longer line (say, tab every 2 units on a line > 12 units). (Note: If you enable both options, the single tab will take precedence over the multiple tab option, for a single line that satisfies both criteria. At least I believe that is the case.) Also, the tab width is hard coded as the tool diameter, but that could be a dialog option pretty easily.

Like I said, it's pretty basic and was written to satisfy a specific need that I had. Another limitation is that you have to key in your FINAL DOC in order to trigger the tabbing operation on the final cutting operation. If you get this value wrong, you will not get ANY tabs. So, if your final cut happens at Z level = 0.0, then you need to use this value. It should equal your "top of part" - "total depth".

If you already have a modified post, then the integration is kind of tricky. It amounts to hooking up specific post operations with my overridden behavior. I can explain this in detail, or it's covered over in the BobCAD support forum in the Post area. If you have programming experience, it's pretty trivial (but nasty and kludgy). The whole post interface is clumsy as heck and provides just enough functionality to be a tease, without giving you enough to do more sophisticated processing. That's one reason why I could never get tabs to work for arcs.

When you generate your tool paths you will NOT see changes on the screen. You will NOT see the tabs because it is happening on the post and is not visually represented by BobCAD. You will also NOT see the tabs if you use the BobCAD "verify" function because it does not operate on the NC code, but on the generated toolpaths without the post modifications. Argh. You should see them if you are using the Predator simulation module, but I don't own that, so I can't be completely sure. If it interprets the NC code, it should work fine.

You should see some comments in the NC posted code that the tabbing is happening, and you should verify them with NCPlot, which I find is always a good idea before actually running the code. You will also see them with Mach as a final sanity check. If you are doing many fine downward Z movements, the tab will ONLY appear on the final movement, regardless of what you have entered in the tab height dialog. This could be fixed, but wasn't necessary for my needs.

A side benefit of my custom post is that is also includes the "Crop Circle Arc Fix" in Program_Block_7. There should be no harm in running this, as all it does is turn tiny little arc instructions into straight line movements. You can comment it out if you'd like, but I'll leave it there because I find it very helpful with certain types of artwork.

Steve

[Magnum164]

Magnum164,
Here's the file. The only settings made are the stock properties, the top of part and depth of cut settings. It seems to tab. If you look at these values, see if you can then figure out how to get it to tab at a particular depth.

Seems the only obstacle is for having it tab at other than 2d depths??? You mentioned 3d models. This example is for using 2d geometry to have the profile operation work with contours. I have recently been fooling around with using the z level finish 3d toolpath as a profiling op on 3d geometry. I think it would work pretty good for this too, but havnt done any specific example. I think for it to work well with the z-level op as a tabbing source, the "boundry" would need to force that "rapid between tabs"....I dont know if it would work this way or not. If you have an example, I would like to look at it with you.

I finally got to call BobCAD yesterday. Seems they are having posting problems with the current version on 64bit machines so I had to reinstall back a few builds. They said they just found the problem, but I turned in a ticket with the problem several weeks ago. Anyway I have the file now and can post and also run through predator.... I'll give it one more try

[Magnum164]

After looking over this I think I may have found a easy solution. For me anyways. Everything I do will be a solid model, even 2D will be extruded when sending to BobCAD.

This can be done in either BobCAD or the main software. I may opt to use in BobCAD since it is strictly a manufacturing process. For tabs simply create a solid block the size of the material or tab you want to remain for removal. Then boolean add this to your existing solid part. Then when you are finished with the machining you are left with just removing the tabs.

At first I didn't want to do this as my background is more mechanical design (ie. only draw the final product). After talking to a friend who is a career CNC programmer/machinist he said they do this with their parts and most of the time they completely redraw the parts anyway to make sure they are done correctly. Just have to remember I am doing both engineering and manufacturing now

[stevespo]

Yes, that sounds like the easiest approach for your application. Just adjust your boundary and extents to include the tabs, and tool paths like slice planar should create them as part of the standard machining process.

Steve

[Claude Boudreau]

Was able to load these files , tried a few settings , not sure how this work, Dont see it in verify , dont have predator either, dont show up in gcode , dont appear in mach simulation...are you supposed to see z movements on DRO when doing a simulation in mach3? or do you have to actually cut to see...(If your top of material is at z=0 and stock thickness is .75 do you put -.75 for final DOC?)

Here are some things to play around with
If you're using an unmodified Mach3-Router.MillPst then the easiest thing is to just drop these two files (look in the .zip archive for ArcFix-Mach3-Router.MillPst and ArcFix-Mach3-Router.CustomContour) into your C:\Program Files\BobCAD-CAM\BobCAD-CAM V23\Posts\Mill folder, and then select them as your active Milling Stock Post in the CAM Tree Manager.

When you are using a 2d Profiling toolpath, it provides a new Adv Posting dialog that allows you to turn on/off tabbing for that given profile. There aren't a lot of options, and they aren't very sophisticated. You can choose to put a single tab on a line that fits a given range for length (ie. > 1 and < 2 units), or you can choose to put multiple tabs on a longer line (say, tab every 2 units on a line > 12 units). (Note: If you enable both options, the single tab will take precedence over the multiple tab option, for a single line that satisfies both criteria. At least I believe that is the case.) Also, the tab width is hard coded as the tool diameter, but that could be a dialog option pretty easily.

Like I said, it's pretty basic and was written to satisfy a specific need that I had. Another limitation is that you have to key in your FINAL DOC in order to trigger the tabbing operation on the final cutting operation. If you get this value wrong, you will not get ANY tabs. So, if your final cut happens at Z level = 0.0, then you need to use this value. It should equal your "top of part" - "total depth".

If you already have a modified post, then the integration is kind of tricky. It amounts to hooking up specific post operations with my overridden behavior. I can explain this in detail, or it's covered over in the BobCAD support forum in the Post area. If you have programming experience, it's pretty trivial (but nasty and kludgy). The whole post interface is clumsy as heck and provides just enough functionality to be a tease, without giving you enough to do more sophisticated processing. That's one reason why I could never get tabs to work for arcs.

When you generate your tool paths you will NOT see changes on the screen. You will NOT see the tabs because it is happening on the post and is not visually represented by BobCAD. You will also NOT see the tabs if you use the BobCAD "verify" function because it does not operate on the NC code, but on the generated toolpaths without the post modifications. Argh. You should see them if you are using the Predator simulation module, but I don't own that, so I can't be completely sure. If it interprets the NC code, it should work fine.

You should see some comments in the NC posted code that the tabbing is happening, and you should verify them with NCPlot, which I find is always a good idea before actually running the code. You will also see them with Mach as a final sanity check. If you are doing many fine downward Z movements, the tab will ONLY appear on the final movement, regardless of what you have entered in the tab height dialog. This could be fixed, but wasn't necessary for my needs.

A side benefit of my custom post is that is also includes the "Crop Circle Arc Fix" in Program_Block_7. There should be no harm in running this, as all it does is turn tiny little arc instructions into straight line movements. You can comment it out if you'd like, but I'll leave it there because I find it very helpful with certain types of artwork.

Steve

[stevespo]

Claude, yes it is confusing. The scripting API is very primitive and that is the best I could come up with. My needs were also pretty basic, but it does work well.

Are you seeing the custom dialog under the Advanced Posting tab? What have you entered for values?
You are correct that if top of material is 0.0 and stock thickness is .75, then final DOC is -.75, provided you are cutting all the way through the part.

Remember, this will only insert tabs on straight line segments. You need to accurately enter what your final Z cutting height is, or you will not get any tabs. You can then configure how many tabs you want on each line segment, and have some level of control over which segments will get a tab (based on length).

The example (simple-tab-test.bbcd) will show how it works.

When you post the code, you will NOT see changes in the drawing on the screen. You will NOT see these tabs in the built in verify function. If you post the code, you SHOULD see some comments in the code that indicate where the tabs are happening. You WILL then see them displayed in a program like NCPlot, or just by loading the NC file into Mach and rotating the object so you can see the Z tool paths.

Steve

N01 G01 Z.25 F60.
N02 Y-.75 F120.
N03 G17 G03 X-.75 Y-1.0625 I.3125 J0.
N04 G01 X.75
N05 G03 X1.0625 Y-.75 I0. J.3125
N06 G01 Y.75
N07 G03 X.75 Y1.0625 I-.3125 J0.
N08 G01 X-.75
N09 G03 X-1.0625 Y.75 I0. J-.3125
(*** Downward ZFeed: Contour Final Pass ***)
N10 G01 Z0. F60.
(*** Start Tab ***)
N11 Y.125 F120.
N12 Z.1
N13 Y-.125
N14 Z0.
(*** End Tab ***)
N15 Y-.75
N16 G03 X-.75 Y-1.0625 I.3125 J0.
(*** Start Tab ***)
N17 G01 X-.125
N18 Z.1
N19 X.125
N20 Z0.
(*** End Tab ***)

[moldmker]

.... For tabs simply create a solid block the size of the material or tab you want to remain for removal. Then boolean add this to your existing solid part.....

You don't even need to Boolean Add these tabs.

Just create them, they can intersect the model, no need for stitching either.
Then select them along with your model as your Geometry.

I put items such as this on their own layer.
They can then be turned on and off, as needed.

[Claude Boudreau]

On your sample tab file, the straight entities are 1.5 unit long so you should get tabs ok. I dont see any indication of tabs in the post...

Claude, yes it is confusing. The scripting API is very primitive and that is the best I could come up with. My needs were also pretty basic, but it does work well.

Are you seeing the custom dialog under the Advanced Posting tab? What have you entered for values?
You are correct that if top of material is 0.0 and stock thickness is .75, then final DOC is -.75, provided you are cutting all the way through the part.

Remember, this will only insert tabs on straight line segments. You need to accurately enter what your final Z cutting height is, or you will not get any tabs. You can then configure how many tabs you want on each line segment, and have some level of control over which segments will get a tab (based on length).

The example (simple-tab-test.bbcd) will show how it works.

When you post the code, you will NOT see changes in the drawing on the screen. You will NOT see these tabs in the built in verify function. If you post the code, you SHOULD see some comments in the code that indicate where the tabs are happening. You WILL then see them displayed in a program like NCPlot, or just by loading the NC file into Mach and rotating the object so you can see the Z tool paths.

Steve

N01 G01 Z.25 F60.
N02 Y-.75 F120.
N03 G17 G03 X-.75 Y-1.0625 I.3125 J0.
N04 G01 X.75
N05 G03 X1.0625 Y-.75 I0. J.3125
N06 G01 Y.75
N07 G03 X.75 Y1.0625 I-.3125 J0.
N08 G01 X-.75
N09 G03 X-1.0625 Y.75 I0. J-.3125
(*** Downward ZFeed: Contour Final Pass ***)
N10 G01 Z0. F60.
(*** Start Tab ***)
N11 Y.125 F120.
N12 Z.1
N13 Y-.125
N14 Z0.
(*** End Tab ***)
N15 Y-.75
N16 G03 X-.75 Y-1.0625 I.3125 J0.
(*** Start Tab ***)
N17 G01 X-.125
N18 Z.1
N19 X.125
N20 Z0.
(*** End Tab ***)

[stevespo]

Claude, can you describe to me what you are doing?

When you load the sample file (simple-tab-test.bbcd), make sure you have the ArcFix-Mach3-Router.MillPst selected as the post processor.
By default, the example should put one tab on each line segment. Then just Post the code, and you'll see the comments embedded that describe what is happening with the tabs.

You won't physically see the tabs because they're not part of the actual on-screen model.
Can you describe what is happening, and post the code that is being generated?

Steve

[stevespo]

If I take the simple example, and modify the advanced posting options, it is easy to place two tabs on each side, by disabling the first option and enabling the second with these params (see images).

I'm really not sure if anyone else has even tried this post processor so it would be helpful for me to understand what problems you are encountering. It could be something that I am overlooking or specific to my environment.

Thanks,

Steve

[Claude Boudreau]

If I take the simple example, and modify the advanced posting options, it is easy to place two tabs on each side, by disabling the first option and enabling the second with these params (see images).

I'm really not sure if anyone else has even tried this post processor so it would be helpful for me to understand what problems you are encountering. It could be something that I am overlooking or specific to my environment.

Thanks,

Steve

Sorry Steve,
I m always working at home with my laptop witch is loaded with the trial version of bobcad . Thats why I did not see anything in post , just some basic moves no real gcode.
So I try it today in my shop where it work fine , I can see it in the Gcode, also in preview when loaded in Mach3.
Should work fine,cant wait to do a real run . Thanks I knew there was a good soul somewhere to help make the blind man see...

[stevespo]

Claude,

Glad to hear that the post processor is working ok.

I have not used it recently, and it was only intended to do the basic operations that I needed. Arc support is something that may never work, but I could certainly add more options for the straight line movements if that would be helpful.

So, please run it on some artwork and see what you think. I would be happy to make some improvements, so any feedback is appreciated.

Steve

[Claude Boudreau]

Claude,

Glad to hear that the post processor is working ok.

I have not used it recently, and it was only intended to do the basic operations that I needed. Arc support is something that may never work, but I could certainly add more options for the straight line movements if that would be helpful.

So, please run it on some artwork and see what you think. I would be happy to make some improvements, so any feedback is appreciated.

Steve

This is an old project that I will use for a trial run,good example for straight line only limitations.
Now my straight line on the logo are between 1 and 2 units long.
Can you use the second option in this case to create one tab on each lines?