Mid tape DNC

[nervis1]

Anyone have a quick and dirty tutorial on how to do a mid program DNC start?

I broke a 1/8 th end mill halfway through a 6 hr program this weekend, I got a bald spot about an hour later.

Ugh.

[HuFlungDung]

Nervis1,

The trick is to find out what line to begin on. If you happen to know this, then you can just copy and paste your program start lines and insert it into the program at the proper position. Then do a program search to find this new start point.

Make sure that the proper tool change has been accomplished.

Give yourself a little leeway by starting a bit earlier than you need to. If you can single step for a while in DNC mode, this would be advised, with the Rapid override turned way down. Once the tool looks like it is approaching the right pathway, then you can open the feed back up

Or,
you could draw a new boundary over your part representing where the machining needs to continue, and generate a new program, just as though it were "Rest machining".

Give your spindle a few minutes of run time to warm up before you begin the cut.

[Neal]

Nervis--
Quickest and dirtyest (sp) method of doing a mid-tape start is to go to ENTER NEXT COMMAND and type AU,150 where the 150 represents the block number that you want to start at. This will cause the control to rapidly read thru the program and set all the modal codes needed at the starting block. When the search is done the control will go into the WAiTING state now just hit AUTO and your running.
The only caution is do not start in the middle of a drill or tap cycle or the middle of a subroutine or sub program.

Neal

[Rekd]

There are other parameters for AU that allow you to search from a specified start point instead of the beginning, as well as other things. They're in the manual, check them out. Not sure if AU will work with DNC though.

'Rekd

[nervis1]

The manual says to use the memory manager software to specify the start point. I can't see that as an option in the software I have. It just starts at the beginning. I ended up splitting the program, editing it for the tool changes and re-loading at the break point.

Will the AU,# command work with DNC as well?

I know I've used it on memory loaded programs with no trouble at all.

[Neal]

Nervis--
OOOPPPS! You're right the AU command is for on board memory use only. Another senior moment got me! :=( Most DNC software will have some sequence for searching to do a mid-tape start. What software are you using? If its NC Fadal the in the DNC dialog box just state the desired starting block and whether to search for modals or not and the software will take over from there.

Neal

[nervis1]

That would lead me to my next question Neal. I have NC Fadal but I can not get it to communicate with my controller for the life of me. I tried letting it auto configure, 32MP mode, and everything in between...any thing I could be missing? NC Fadal would be the way to go wouldn't it. I have it loaded on the hard drive of the 32 MP.

Don't sweat the oversight I'm certain you have forgotten more about Fadal machines than I'll ever know.

[Neal]

Nervis--
Do not use the 32MP mode as this looks for an RS-422 port and locks out the baud rate selections. Make sure that you have the latest service packs from Microsoft for your Windows System and Internet Explorer 6.0 or later. There were some bug from Microsoft that were corrected with this fix.
Make sure that the VMC baud rate and the NC Fadal baud rate are the same. 'member that if you change the baud rate in the VMC SETP pages you MUST power off and then power back on for it to be effective. Temporarily you could use the CD command to over ride that SETP paramteter.
Make sure that you cable is wired correctly and a null modem is used if the cable is NOT wired null. Check your pin assignments closely. Diagrams are in the User's Manual in the communications section.

NEal

[cadman]

Originally posted by nervis1
I have it loaded on the hard drive of the 32 MP.

NC Fadal is supposed to be installed on the computer you are using as the server, not the controller.

[Neal]

If it is loaded on to a 32MP control then you MUST select the 32MP Mode in the View/Options screens as without that selected NC Fadal will look for an RS-232 which it ain't gonna find. The 32MP mode will look for the RS-422 and also you MUST set COMM 2. Comm 1 is the rs-232 at the rear of the Pendant.
Neal

[Rchapp]

Go Into Program Where You Want To Start.
Find A X Y Position That Has A Z Downfeed Move Before
That Position. If Needed Add Couple Of Extra Lines To Position
To X Y Position And Add Z Down Move. When You Have Determined
What Line You Want To Start At Change The Line Number To A Unique Number If The Line Number Is N1000 Change It To N1000.5
Because If Your Using Dnc You Probably Have Multiple N1000 Lines In The Program. At The Enter Next Command Line Type Dnc,n1000.5
And Enter Then Start Dnc Tranfer At Computer. You Will See Prg Look Like It Is Loading Into Memory And It Will Stop When It See's
N1000.5 Line. This Method Will Not Take Anything Into Consideration In Prg Prior To This Point. It Is Not The Same As
The Au,1000.5 Way Of Starting A Prg But It Will Work. Some Dnc
Prg's Like Surfcam Have A Dnc Restart Feature In Them I Haven't Had Much Luck With Them But Haven't Put That Much Effort Into Setting Them Up Either. Hope This Helps.

[nervis1]

Well, I gave up a long time ago, the DNC business was so much more of a hassle than running from the on board memory...I went and got a 4 meg memory card. Problem solved.

I certainly appreciate all of the advice though.