Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: pgsierra on November 11, 2008, 10:38:05 AM

Title: What to do after a loss of Power?
Post by: pgsierra on November 11, 2008, 10:38:05 AM
Folks,

First of all... thanks to the help of Ray, Hood and countless others I have managed to get everything up and running...  Thank You!

I'll post some pictures shortly....


Everything was working great until I lost power last night half way through the machining process...  barley noticed as it wasn't enough to slow the router down, but the PC had to reboot.

Of course, afterwards I had to re-load Mach and the G-Code....

Here's my question ( I think I know the answer already) Is there a way to continue the machining process where it left off?  I have not moved the router however when I loaded the G-code back it zeroed everything at the point that the router stopped. Keep in mind that I do not know what line of G-code the machining stopped at, and of course, I am starting at line 1 again.


If not, and I have to start over, is there a good way to insure correct registration ?  or do I scrap the piece?

Thanks in advance,

Pete
Title: Re: What to do after a loss of Power?
Post by: HimyKabibble on November 11, 2008, 11:04:00 AM
Pete,

   This is something you have to think about up-front.  You should always assume something *will* go wrong, and provide a means of re-zeroing the machine after a position loss.  This can be something as simple as putting a hole in a known location, or referencing your "zero" point to a corner or two edges of the work piece.  I will often put a 1/4" hole in my pieces, in a location that will NOT get machined off until the last operation.  If I lose position, I can move the machine until a 1/4" rod in the chuck will just drop cleanly into the hole, then set the DROs to the known position of that hole.  You can do the same by using an edge finder on any two perpendicular edges of the workpiece.  All my fixture plates have the front-left corner milled to a perfect right angle for this purpose.

    If you haven't made a provision for this in your current part, you need to find edges or holes you can use, and look at either the G-code or CAD drawing to determine the exact locations of those features.

Regards,
Ray L.
Title: Re: What to do after a loss of Power?
Post by: Chaoticone on November 11, 2008, 11:06:55 AM
Pete, I think most will set up like this. When you first fire the machine up or bring it out of an e-stop ref. the machine. If it has hiome switches and all is well, it should repeat to the same posotion each time you home. Form there you can command it go to your work coords. and it should re run fine. If it doesn't have home switches, I'd put a ref. mark on the work that I could re-register to during set up of the job. A simple peck with a drill so you can use a center finder will do. If you don't have a register mark or home switches, it may be tuff to save, depending on tolerances and such.

Brett
Title: Re: What to do after a loss of Power?
Post by: pgsierra on November 11, 2008, 11:28:44 AM
Thanks for the feedback...

Really great suggestions, and a best practice I will incorporate going forward.

Pete

Title: Re: What to do after a loss of Power?
Post by: Chaoticone on November 11, 2008, 01:38:58 PM
No problem Pete.  :)

Brett