path rules have no drop down to turn off/on THC - why

[Tomtrain]

I have my paid licence for sheetcam few years now, do I have to reinstall my licence since I'm having difficulty in making path rules for small circles but cannot turn on or off the THC.
I have watched many tutorials but my previous version (png) downloaded version and recently downloaded versiondoes not have any drop down for the THC on/off , and if I manually type in "turn THC off or on it does not show up in the path rule.
Seems there should be a tutorial of F1 documentation to clarify this
help

[adbuch]

Click on the link below to download the SheetCam Path Rules file for Hypertherm.



Then go to "Options, Job Options, Path Rules, Load" and load your path rules.

Then under "Operation, Jet Cutting, Basic, Path Rules" pick the particular rules or rules you wish to apply.

David

[adbuch]

Here is some information on editing SheetCam path rules to turn THC on/off.
David

https://support.machmotion.com/books/so ... path-rules

[acourtjester]

Not sure is that is a difference but I have always used the development version of SheetCam. Another thing you need to use the codes that work for you electronics (post processor). Attached are screen shots of a path rule I used for turning off the THC in LinuxCNC, I had to use M62, and M63 to turn it on. These codes are different for some software. I create the rule under tools then cutting rules selecting the different perimeters for what I want to do.

[adbuch]

Tom - this is the SheetCam version I am using. I'm not sure how this relates to the development version you are using. Do you know what the differences might be?

Thanks,
David

[acourtjester]

I cannot really say what the differences is as I made that decision when I started out with SheetCam. I think I heard there may be more options with the developer version, Les may hope in a give the real reason.

[djreiswig]

The development version has new features and changes that might not be stable, so there might be odd behaviors. If you look at the download area on the website you can see recent changes to both versions.

[adbuch]

The development version has new features and changes that might not be stable, so there might be odd behaviors. If you look at the download area on the website you can see recent changes to both versions.

Djreiswig - thanks for that! I will have a look at the download area. The version I have says that it is the latest version - but it might be interesting to know what features from the development version have made it into the latest stable version.

David

[acourtjester]

The developer version gets updates when ever bugs are reported, I have been using it for years without problem. When I have had code problems Les has answered questions quickly. Last one was on setting up a cut rule for LInuxCNC and Les gave me the info on which codes to use.
viewtopic.php?t=35663&start=75

[Tomtrain]

A couple days ago I responded to this link asking for clarification to the first reply to this thread, my reply never got published and still not attached to this thread. I am a newbie when it comes to plasma spider forum , I'm just trying to improve my internal cuts specifically with small circles.
I am a total loss with trying to develop some path rules, I have followed a good number or tutorials but my understanding of what is required makes me want to quit wasting my time because I dont know what specific questions I need answered. I cant seem to locate a tutorial or Sheetcam tutorial for the newbie in me, there is something I am missing here. I see mention of "code snipet" where does one go to learn about this ? Do I need to learn about developing GCODE from another source. My machine is a Langmuir Crossfire XL using their firecontrol to do the cuts, I develop my DXF file with V carve Pro, export that DXF file to Sheetcam then after post procseeing go over to firecontrol. sorry for rant, just tired of not knowing where to go from here

[adbuch]

A couple days ago I responded to this link asking for clarification to the first reply to this thread, my reply never got published and still not attached to this thread. I am a newbie when it comes to plasma spider forum , I'm just trying to improve my internal cuts specifically with small circles.
I am a total loss with trying to develop some path rules, I have followed a good number or tutorials but my understanding of what is required makes me want to quit wasting my time because I dont know what specific questions I need answered. I cant seem to locate a tutorial or Sheetcam tutorial for the newbie in me, there is something I am missing here. I see mention of "code snipet" where does one go to learn about this ? Do I need to learn about developing GCODE from another source. My machine is a Langmuir Crossfire XL using their firecontrol to do the cuts, I develop my DXF file with V carve Pro, export that DXF file to Sheetcam then after post procseeing go over to firecontrol. sorry for rant, just tired of not knowing where to go from here

https://forum.langmuirsystems.com/t/hol ... ules/19658

[adbuch]

A couple days ago I responded to this link asking for clarification to the first reply to this thread, my reply never got published and still not attached to this thread. I am a newbie when it comes to plasma spider forum ,.............

You may have been looking at your response in Preview mode and forgot to click on the "Submit" button. I have done the same on more than one occasion.

David

[tcaudle]

Well here is the thing about Cut Rules : They are dependant on the dialect of Gcode your controller uses. Unfortunately the "language" CNC uses on most motion control is GCode but past the few basic codes there are dozens if not more variations of it . One controller my turn the torch on and off using normal G3 and G5 calls where as others may use a custom Gcode . You have to discover the codes YOUR controller uses. That should be documented in your nauseam or instructions

It get trickier when the THC is involved. Some machines let you enable and disable the THC via a GCode and its usually a specific call. The other consideration is some codes happen "in motion" (as you cut) "and other are static, meaning they execute as a separate command so can't happen in the middle of a move line or it pauses motion.

code snitps are simple single lines of gcode that get called byte "trigger" (Path Rule) There are various triggers (types) . One is smallholes and you difine what the min hole size is to "trigger" that rule and it runs the code snip you generate to do what you want. One may be to turn off the THC while it may also slow down the feedrate (which is recommended on smaller holes)

The cut rules run code snips . Th e code snip live in the tool set in SheetCAM . You can call a rule in each operation OR you can make it global bay assigning it to a Path Rule.

Another important concept is to use the leavers and operations in SheetCAm to control how you cut a job. If you place all of the holes on a separate layer and IF your POST has defined an option to do an operation without the THC active then you simply use that option and don't worry about path rules .

Path rules can get overdone . About the only one that is universal is the End of Cut rule that should turn off the THC BEFORE the end of cut to prevent diving as the torch approaches the beginning cut.
So find out what codes (if any) that your THC uses to turn on and off. If you do turn it off don't forget to also turn it back on again on the next cut.
Who knows! maybe your table vendor already has some canned Code snips or even better tool sets with the snips included that you can get from them

[acourtjester]

Tomtrain you are facing what many of use have, this is a new thing and will take some time to get things sorted out. Keep asking questions as with many thing some one out there has the answer you need. Plasma Spider has a large knowledge base how we each explain things may be different, and see thing differently. This sign does not help you out but may help you understand where you are at. You will get there some of us are still looking.

robert.JPG (65.25 KiB) Viewed 140 times

[Tomtrain]

to you last three gents who have responded to my latest plea, you have all helped me keep my sanity as you have ll answered my questions. I will now check further with Langmuir systems. thank you all who have chimed in.

[tcaudle]

I had a look at the POST for SheetCAM for the Langmuir and I don't see any way to do it in=motion path rules. The THC enable and disable are in the PenDown (pierce and beginning of a cut) and the Pen UP (end of a cut) and just tell it it switch back and forth between THC control of the Z or Gcode control of the Z. Looks like its based on the SP Promo THC. An "H0" call puts it in Gcode format. The H1 puts it in THC mode .

I guess you could do a rule that called the H0 code but not sure what that would do in the middle of a cut. In fact it would cause a pause in motion. So you would have to make it happen for the whole cut . To run before each hole you want no THC on.

since it would have to stay off for the entirety iof that cut you dont have to wroory abot turning iot back on. That happens every Pen down . Trick would be to override that in the POST if it was turned off in the settings.

ShetCAm will let you add variables and input boxes into the Operations and tool settings and you can do logic coding in the POST . You could test to see if the THC off was set for that operation and simply not turn it on .

The touch off sequence is separate (also in the Pen down) so that would stay.

Honestly I think it beetler done with a change to the POST than with a Cut Rule.

[adbuch]

A couple days ago I responded to this link asking for clarification to the first reply to this thread, my reply never got published and still not attached to this thread. I am a newbie when it comes to plasma spider forum , I'm just trying to improve my internal cuts specifically with small circles.

Tomtrain - With regard to your second question about internal cuts with small circles, I think the easiest thing to do would be as Tom suggested - simply create a separate layer for your small circles and set your cut speed accordingly. This may be easier to implement than worrying about specific path rules. I don't think the ability to turn your thc on or off should have anything to do with the cut quality of your small circles. With the Plasmacam Design Edge program I use for my table, it offers the ability to automatically go slower on curves and circles under a specified radius.

David

[tcaudle]

One of the real important features of SheeCAm is the level of control you can exercise over the cutting process. I know everybody wants to load a file , push a button, and it cuts perfect. Learning how to organize your cuts and pick the sequence and HOW they cut greatly improves the outcome on most jobs and especially on ones that are more difficult. So selecting the holes , putting them on New Layer and name it "holes" and then setup a different Operation to cut that layer and specific HOW the holes are to be cut. unfortunately there may be no way to disable the THC in the base POST provided but That option would be easy to add . The problem with just slowing down the feedrates on the holes is that slower feedrates mean high torch volts and that equals torch dive from the THC.

The current POST turns on the THC every time it start a new cut (segment) so it touches off, moves to pierce height fires the torch and turns on the THC that hen takes over the Z axis to control the height. AI check box added to Operations to "Diable THC" could then just read that variable and skip turn the THC ON in the pen down function.

Not sure what side effects that might have (if any) but its about all that can be done with that level of THC .

[adbuch]

The problem with just slowing down the feedrates on the holes is that slower feedrates mean high torch volts and that equals torch dive from the THC.